Commit Graph

580 Commits

Author SHA1 Message Date
Linus Torvalds e2a0883e40 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs pile 1 from Al Viro:
 "This is _not_ all; in particular, Miklos' and Jan's stuff is not there
  yet."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits)
  ext4: initialization of ext4_li_mtx needs to be done earlier
  debugfs-related mode_t whack-a-mole
  hfsplus: add an ioctl to bless files
  hfsplus: change finder_info to u32
  hfsplus: initialise userflags
  qnx4: new helper - try_extent()
  qnx4: get rid of qnx4_bread/qnx4_getblk
  take removal of PF_FORKNOEXEC to flush_old_exec()
  trim includes in inode.c
  um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it
  um: embed ->stub_pages[] into mmu_context
  gadgetfs: list_for_each_safe() misuse
  ocfs2: fix leaks on failure exits in module_init
  ecryptfs: make register_filesystem() the last potential failure exit
  ntfs: forgets to unregister sysctls on register_filesystem() failure
  logfs: missing cleanup on register_filesystem() failure
  jfs: mising cleanup on register_filesystem() failure
  make configfs_pin_fs() return root dentry on success
  configfs: configfs_create_dir() has parent dentry in dentry->d_parent
  configfs: sanitize configfs_create()
  ...
2012-03-21 13:36:41 -07:00
Al Viro 48fde701af switch open-coded instances of d_make_root() to new helper
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-20 21:29:35 -04:00
Chris Metcalf 48b25c43e6 [PATCH v3] ipc: provide generic compat versions of IPC syscalls
When using the "compat" APIs, architectures will generally want to
be able to make direct syscalls to msgsnd(), shmctl(), etc., and
in the kernel we would want them to be handled directly by
compat_sys_xxx() functions, as is true for other compat syscalls.

However, for historical reasons, several of the existing compat IPC
syscalls do not do this.  semctl() expects a pointer to the fourth
argument, instead of the fourth argument itself.  msgsnd(), msgrcv()
and shmat() expect arguments in different order.

This change adds an ARCH_WANT_OLD_COMPAT_IPC config option that can be
set to preserve this behavior for ports that use it (x86, sparc, powerpc,
s390, and mips).  No actual semantics are changed for those architectures,
and there is only a minimal amount of code refactoring in ipc/compat.c.

Newer architectures like tile (and perhaps future architectures such
as arm64 and unicore64) should not select this option, and thus can
avoid having any IPC-specific code at all in their architecture-specific
compat layer.  In the same vein, if this option is not selected, IPC_64
mode is assumed, since that's what the <asm-generic> headers expect.

The workaround code in "tile" for msgsnd() and msgrcv() is removed
with this change; it also fixes the bug that shmat() and semctl() were
not being properly handled.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-03-15 13:13:38 -04:00
Al Viro 4040153087 security: trim security.h
Trim security.h

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-14 10:45:42 +11:00
Hugh Dickins 245132643e SHM_UNLOCK: fix Unevictable pages stranded after swap
Commit cc39c6a9bb ("mm: account skipped entries to avoid looping in
find_get_pages") correctly fixed an infinite loop; but left a problem
that find_get_pages() on shmem would return 0 (appearing to callers to
mean end of tree) when it meets a run of nr_pages swap entries.

The only uses of find_get_pages() on shmem are via pagevec_lookup(),
called from invalidate_mapping_pages(), and from shmctl SHM_UNLOCK's
scan_mapping_unevictable_pages().  The first is already commented, and
not worth worrying about; but the second can leave pages on the
Unevictable list after an unusual sequence of swapping and locking.

Fix that by using shmem_find_get_pages_and_swap() (then ignoring the
swap) instead of pagevec_lookup().

But I don't want to contaminate vmscan.c with shmem internals, nor
shmem.c with LRU locking.  So move scan_mapping_unevictable_pages() into
shmem.c, renaming it shmem_unlock_mapping(); and rename
check_move_unevictable_page() to check_move_unevictable_pages(), looping
down an array of pages, oftentimes under the same lock.

Leave out the "rotate unevictable list" block: that's a leftover from
when this was used for /proc/sys/vm/scan_unevictable_pages, whose flawed
handling involved looking at pages at tail of LRU.

Was there significance to the sequence first ClearPageUnevictable, then
test page_evictable, then SetPageUnevictable here? I think not, we're
under LRU lock, and have no barriers between those.

Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michel Lespinasse <walken@google.com>
Cc: <stable@vger.kernel.org> [back to 3.1 but will need respins]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-23 08:38:48 -08:00
Hugh Dickins 85046579bd SHM_UNLOCK: fix long unpreemptible section
scan_mapping_unevictable_pages() is used to make SysV SHM_LOCKed pages
evictable again once the shared memory is unlocked.  It does this with
pagevec_lookup()s across the whole object (which might occupy most of
memory), and takes 300ms to unlock 7GB here.  A cond_resched() every
PAGEVEC_SIZE pages would be good.

However, KOSAKI-san points out that this is called under shmem.c's
info->lock, and it's also under shm.c's shm_lock(), both spinlocks.
There is no strong reason for that: we need to take these pages off the
unevictable list soonish, but those locks are not required for it.

So move the call to scan_mapping_unevictable_pages() from shmem.c's
unlock handling up to shm.c's unlock handling.  Remove the recently
added barrier, not needed now we have spin_unlock() before the scan.

Use get_file(), with subsequent fput(), to make sure we have a reference
to mapping throughout scan_mapping_unevictable_pages(): that's something
that was previously guaranteed by the shm_lock().

Remove shmctl's lru_add_drain_all(): we don't fault in pages at SHM_LOCK
time, and we lazily discover them to be Unevictable later, so it serves
no purpose for SHM_LOCK; and serves no purpose for SHM_UNLOCK, since
pages still on pagevec are not marked Unevictable.

The original code avoided redundant rescans by checking VM_LOCKED flag
at its level: now avoid them by checking shp's SHM_LOCKED.

The original code called scan_mapping_unevictable_pages() on a locked
area at shm_destroy() time: perhaps we once had accounting cross-checks
which required that, but not now, so skip the overhead and just let
inode eviction deal with them.

Put check_move_unevictable_page() and scan_mapping_unevictable_pages()
under CONFIG_SHMEM (with stub for the TINY case when ramfs is used),
more as comment than to save space; comment them used for SHM_UNLOCK.

Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-23 08:38:48 -08:00
Davidlohr Bueso 2a4e64b8f6 ipc/mqueue: simplify reading msgqueue limit
Because the current task is being used to get the limit, we can simply
use rlimit() instead of task_rlimit().

Signed-off-by: Davidlohr Bueso <dave@gnu.org>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-23 08:38:47 -08:00
Serge E. Hallyn 6b550f9495 user namespace: make signal.c respect user namespaces
ipc/mqueue.c: for __SI_MESQ, convert the uid being sent to recipient's
user namespace. (new, thanks Oleg)

__send_signal: convert current's uid to the recipient's user namespace
for any siginfo which is not SI_FROMKERNEL (patch from Oleg, thanks
again :)

do_notify_parent and do_notify_parent_cldstop: map task's uid to parent's
user namespace

ptrace_signal maps parent's uid into current's user namespace before
including in signal to current.  IIUC Oleg has argued that this shouldn't
matter as the debugger will play with it, but it seems like not converting
the value currently being set is misleading.

Changelog:
Sep 20: Inspired by Oleg's suggestion, define map_cred_ns() helper to
	simplify callers and help make clear what we are translating
        (which uid into which namespace).  Passing the target task would
	make callers even easier to read, but we pass in user_ns because
	current_user_ns() != task_cred_xxx(current, user_ns).
Sep 20: As recommended by Oleg, also put task_pid_vnr() under rcu_read_lock
	in ptrace_signal().
Sep 23: In send_signal(), detect when (user) signal is coming from an
	ancestor or unrelated user namespace.  Pass that on to __send_signal,
	which sets si_uid to 0 or overflowuid if needed.
Oct 12: Base on Oleg's fixup_uid() patch.  On top of that, handle all
	SI_FROMKERNEL cases at callers, because we can't assume sender is
	current in those cases.
Nov 10: (mhelsley) rename fixup_uid to more meaningful usern_fixup_signal_uid
Nov 10: (akpm) make the !CONFIG_USER_NS case clearer

Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
From: Serge Hallyn <serge.hallyn@canonical.com>
Subject: __send_signal: pass q->info, not info, to userns_fixup_signal_uid (v2)

Eric Biederman pointed out that passing info is a bug and could lead to a
NULL pointer deref to boot.

A collection of signal, securebits, filecaps, cap_bounds, and a few other
ltp tests passed with this kernel.

Changelog:
    Nov 18: previous patch missed a leading '&'

Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
From: Dan Carpenter <dan.carpenter@oracle.com>
Subject: ipc/mqueue: lock() => unlock() typo

There was a double lock typo introduced in b085f4bd6b21 "user namespace:
make signal.c respect user namespaces"

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-10 16:30:54 -08:00
Al Viro df0a42837b switch mq_open() to umode_t 2012-01-03 22:55:16 -05:00
Al Viro 1b9d5ff764 mqueue: propagate umode_t
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:55:11 -05:00
Al Viro 4acdaf27eb switch ->create() to umode_t
vfs_create() ignores everything outside of 16bit subset of its
mode argument; switching it to umode_t is obviously equivalent
and it's the only caller of the method

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:53 -05:00
Al Viro 6b520e0565 vfs: fix the stupidity with i_dentry in inode destructors
Seeing that just about every destructor got that INIT_LIST_HEAD() copied into
it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once();
the cost of taking it into inode_init_always() will be negligible for pipes
and sockets and negative for everything else.  Not to mention the removal of
boilerplate code from ->destroy_inode() instances...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:52:40 -05:00
Al Viro 6f686574cc ... and the same kind of leak for mqueue
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-12-09 00:40:21 -05:00
Manfred Spraul e57940d719 ipc/sem.c: remove private structures from public header file
include/linux/sem.h contains several structures that are only used within
ipc/sem.c.

The patch moves them into ipc/sem.c - there is no need to expose the
structures to the whole kernel.

No functional changes, only whitespace cleanups and 80-char per line
fixes.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-02 16:07:01 -07:00
Manfred Spraul 0b0577f608 ipc/sem.c: handle spurious wakeups
semtimedop() does not handle spurious wakeups, it returns -EINTR to user
space.  Most other schedule() users would just loop and not return to user
space.  The patch adds such a loop to semtimedop()

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Reported-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-02 16:07:01 -07:00
Manfred Spraul 3c24783bb2 ipc/sem.c: fix return code race with semop vs. semop +semctl(IPC_RMID)
sys_semtimedop() may return -EIDRM although the semaphore operation
completed successfully:

thread 1:	thread 2:
		semtimedop(), sleeps
semop():
* acquires sem_lock()
		semtimedop() woken up due to timeout
		sem_lock() loops
* notices that thread 2 could be completed.
* performs the operations that thread 2 is sleeping on.
* marks the semaphore operation as IN_WAKEUP
* drops sem_lock(), does wakeup, sets return code to 0
		* thread delayed due to interrupt, whatever
* returns to user space
		* thread still delayed
semctl(IPC_RMID)
* acquires sem_lock()
* ipc_rmid(), ipcp->deleted=1
* drops sem_lock()
		* thread finally continues - but seem_lock()
		  now fails due to ipcp->deleted == 1
		* returns -EIDRM instead of 0

The fix is trivial: Always use the return code in queue.status.

In real world, the race probably doesn't matter:
If the semaphore array is destroyed, the app is probably not interested
if the last operation succeeded or was already cancelled.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Mike Galbraith <efault@gmx.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-02 16:07:01 -07:00
Wanlong Gao 32ea845d5b ipc/mqueue.c: fix wrong use of schedule_hrtimeout_range_clock()
Fix the wrong use of schedule_hrtimeout_range_clock() in wq_sleep(),
although it is harmless for the syscall mq_timed* now.  It was introduced
by 9ca7d8e ("mqueue: Convert message queue timeout to use hrtimers").

Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Cc: Carsten Emde <C.Emde@osadl.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:44 -07:00
Linus Torvalds 140d0b2108 Do 'shm_init_ns()' in an early pure_initcall
This isn't really critical any more, since other patches (commit
298507d4d2cf: "shm: optimize exit_shm()") have caused us to not actually
need to touch the rw_mutex unless there are actual shm segments
associated with the namespace, but we really should do tne shm_init_ns()
earlier than we do now.

This, together with commit 288d5abec8 ("Boot up with usermodehelper
disabled") will mean that we really do initialize the initial ipc
namespace data structure before we run any tasks.

Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-04 19:35:59 -10:00
Vasiliy Kulikov 298507d4d2 shm: optimize exit_shm()
We may optimistically check .in_use == 0 without holding the rw_mutex:
it's the common case, and if it's zero, there certainly won't be any
segments associated with us.

After taking the lock, the idr_for_each() will do the right thing, so we
could now drop the re-check inside the lock without any real cost.  But
it won't hurt.

Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-03 14:45:55 -10:00
Vasiliy Kulikov 33a30ed4bd shm: fix wrong tests
Commit 4c677e2eef ("shm: optimize locking and ipc_namespace getting")
introduced a copy-paste bug.  Due to the bug cycle optimizations were
disabled.

Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-03 14:45:55 -10:00
Vasiliy Kulikov 4c677e2eef shm: optimize locking and ipc_namespace getting
shm_lock() does a lookup of shm segment in shm_ids(ns).ipcs_idr, which
is redundant as we already know shmid_kernel address.  An actual lock is
also not required for reads until we really want to destroy the segment.

exit_shm() and shm_destroy_orphaned() may avoid the loop by checking
whether there is at least one segment in current ipc_namespace.

The check of nsproxy and ipc_ns against NULL is redundant as exit_shm()
is called from do_exit() before the call to exit_notify(), so the
dereferencing current->nsproxy->ipc_ns is guaranteed to be safe.

Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-30 08:44:20 -10:00
Vasiliy Kulikov 5774ed014f shm: handle separate PID namespaces case
shm_try_destroy_orphaned() and shm_try_destroy_current() didn't handle
the case of separate PID namespaces, but a single IPC namespace.  If
there are tasks with the same PID values using the same shmem object,
the wrong destroy decision could be reached.

On shm segment creation store the pointer to the creator task in
shmid_kernel->shm_creator field and zero it on task exit.  Then
use the ->shm_creator insread of shm_cprid in both functions.  As
shmid_kernel object is already locked at this stage, no additional
locking is needed.

Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-30 08:44:19 -10:00
Vasiliy Kulikov b34a6b1da3 ipc: introduce shm_rmid_forced sysctl
Add support for the shm_rmid_forced sysctl.  If set to 1, all shared
memory objects in current ipc namespace will be automatically forced to
use IPC_RMID.

The POSIX way of handling shmem allows one to create shm objects and
call shmdt(), leaving shm object associated with no process, thus
consuming memory not counted via rlimits.

With shm_rmid_forced=1 the shared memory object is counted at least for
one process, so OOM killer may effectively kill the fat process holding
the shared memory.

It obviously breaks POSIX - some programs relying on the feature would
stop working.  So set shm_rmid_forced=1 only if you're sure nobody uses
"orphaned" memory.  Use shm_rmid_forced=0 by default for compatability
reasons.

The feature was previously impemented in -ow as a configure option.

[akpm@linux-foundation.org: fix documentation, per Randy]
[akpm@linux-foundation.org: fix warning]
[akpm@linux-foundation.org: readability/conventionality tweaks]
[akpm@linux-foundation.org: fix shm_rmid_forced/shm_forced_rmid confusion, use standard comment layout]
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Serge E. Hallyn" <serge.hallyn@canonical.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Solar Designer <solar@openwall.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:44 -07:00
Jiri Slaby d40dcdb017 ipc/mqueue.c: fix mq_open() return value
We return ENOMEM from mqueue_get_inode even when we have enough memory.
Namely in case the system rlimit of mqueue was reached.  This error
propagates to mq_queue and user sees the error unexpectedly.  So fix
this up to properly return EMFILE as described in the manpage:

	EMFILE The process already has the maximum number of files and
	       message queues open.

instead of:

	ENOMEM Insufficient memory.

With the previous patch we just switch to ERR_PTR/PTR_ERR/IS_ERR error
handling here.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:44 -07:00
Jiri Slaby 04715206c0 ipc/mqueue.c: refactor failure handling
If new_inode fails to allocate an inode we need only to return with
NULL.  But now we test the opposite and have all the work in a nested
block.  So do the opposite to save one indentation level (and remove
unnecessary line breaks).

This is only a preparation/cleanup for the next patch where we fix up
return values from mqueue_get_inode.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:44 -07:00
Manfred Spraul d694ad62bf ipc/sem.c: fix race with concurrent semtimedop() timeouts and IPC_RMID
If a semaphore array is removed and in parallel a sleeping task is woken
up (signal or timeout, does not matter), then the woken up task does not
wait until wake_up_sem_queue_do() is completed.  This will cause crashes,
because wake_up_sem_queue_do() will read from a stale pointer.

The fix is simple: Regardless of anything, always call get_queue_result().
This function waits until wake_up_sem_queue_do() has finished it's task.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=27142

Reported-by: Yuriy Yevtukhov <yuriy@ucoz.com>
Reported-by: Harald Laabs <kernel@dasr.de>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: <stable@kernel.org>		[2.6.35+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-25 20:57:07 -07:00
Linus Torvalds bbd9d6f7fb Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (107 commits)
  vfs: use ERR_CAST for err-ptr tossing in lookup_instantiate_filp
  isofs: Remove global fs lock
  jffs2: fix IN_DELETE_SELF on overwriting rename() killing a directory
  fix IN_DELETE_SELF on overwriting rename() on ramfs et.al.
  mm/truncate.c: fix build for CONFIG_BLOCK not enabled
  fs:update the NOTE of the file_operations structure
  Remove dead code in dget_parent()
  AFS: Fix silly characters in a comment
  switch d_add_ci() to d_splice_alias() in "found negative" case as well
  simplify gfs2_lookup()
  jfs_lookup(): don't bother with . or ..
  get rid of useless dget_parent() in btrfs rename() and link()
  get rid of useless dget_parent() in fs/btrfs/ioctl.c
  fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers
  drivers: fix up various ->llseek() implementations
  fs: handle SEEK_HOLE/SEEK_DATA properly in all fs's that define their own llseek
  Ext4: handle SEEK_HOLE/SEEK_DATA generically
  Btrfs: implement our own ->llseek
  fs: add SEEK_HOLE and SEEK_DATA flags
  reiserfs: make reiserfs default to barrier=flush
  ...

Fix up trivial conflicts in fs/xfs/linux-2.6/xfs_super.c due to the new
shrinker callout for the inode cache, that clashed with the xfs code to
start the periodic workers later.
2011-07-22 19:02:39 -07:00
Josef Bacik 02c24a8218 fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers
Btrfs needs to be able to control how filemap_write_and_wait_range() is called
in fsync to make it less of a painful operation, so push down taking i_mutex and
the calling of filemap_write_and_wait() down into the ->fsync() handlers.  Some
file systems can drop taking the i_mutex altogether it seems, like ext3 and
ocfs2.  For correctness sake I just pushed everything down in all cases to make
sure that we keep the current behavior the same for everybody, and then each
individual fs maintainer can make up their mind about what to do from there.
Thanks,

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 20:47:59 -04:00
Lai Jiangshan d4ee9aa33d ipc,rcu: Convert call_rcu(ipc_immediate_free) to kfree_rcu()
The rcu callback ipc_immediate_free() just calls a kfree(),
so we use kfree_rcu() instead of the call_rcu(ipc_immediate_free).

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-07-20 14:10:16 -07:00
Lai Jiangshan 693a8b6eec ipc,rcu: Convert call_rcu(free_un) to kfree_rcu()
The rcu callback free_un() just calls a kfree(),
so we use kfree_rcu() instead of the call_rcu(free_un).

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Manfred Spraul <manfred@colorfullife.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-07-20 14:10:16 -07:00
KOSAKI Motohiro ca16d140af mm: don't access vm_flags as 'int'
The type of vma->vm_flags is 'unsigned long'. Neither 'int' nor
'unsigned int'. This patch fixes such misuse.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
[ Changed to use a typedef - we'll extend it to cover more cases
  later, since there has been discussion about making it a 64-bit
  type..                      - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26 09:20:31 -07:00
Eric W. Biederman a00eaf11a2 ns proc: Add support for the ipc namespace
Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2011-05-10 14:35:47 -07:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Randy Dunlap 6213cfe824 ipc: fix util.c kernel-doc warnings
Fix ipc/util.c kernel-doc warnings:

  Warning(ipc/util.c:336): No description found for parameter 'ns'
  Warning(ipc/util.c:620): No description found for parameter 'ns'
  Warning(ipc/util.c:790): No description found for parameter 'ns'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Reviewed-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-27 19:30:19 -07:00
Xiaotian Feng be4d250ab4 ipcns: fix use after free in free_ipc_ns()
commit b515498 ("userns: add a user namespace owner of ipc ns") added a
user namespace owner of ipc ns, but it also introduced a use after free in
free_ipc_ns().

Signed-off-by: Xiaotian Feng <dfeng@redhat.com>
Acked-by: "Serge E. Hallyn" <serge.hallyn@canonical.com>
Acked-by: David Howells <dhowells@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-25 17:45:16 -07:00
Serge E. Hallyn b0e77598f8 userns: user namespaces: convert several capable() calls
CAP_IPC_OWNER and CAP_IPC_LOCK can be checked against current_user_ns(),
because the resource comes from current's own ipc namespace.

setuid/setgid are to uids in own namespace, so again checks can be against
current_user_ns().

Changelog:
	Jan 11: Use task_ns_capable() in place of sched_capable().
	Jan 11: Use nsown_capable() as suggested by Bastian Blank.
	Jan 11: Clarify (hopefully) some logic in futex and sched.c
	Feb 15: use ns_capable for ipc, not nsown_capable
	Feb 23: let copy_ipcs handle setting ipc_ns->user_ns
	Feb 23: pass ns down rather than taking it from current

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Acked-by: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:47:08 -07:00
Serge E. Hallyn b515498f5b userns: add a user namespace owner of ipc ns
Changelog:
	Feb 15: Don't set new ipc->user_ns if we didn't create a new
		ipc_ns.
	Feb 23: Move extern declaration to ipc_namespace.h, and group
		fwd declarations at top.

Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Acked-by: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:47:07 -07:00
Nick Piggin fa0d7e3de6 fs: icache RCU free inodes
RCU free the struct inode. This will allow:

- Subsequent store-free path walking patch. The inode must be consulted for
  permissions when walking, so an RCU inode reference is a must.
- sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
  to take i_lock no longer need to take sb_inode_list_lock to walk the list in
  the first place. This will simplify and optimize locking.
- Could remove some nested trylock loops in dcache code
- Could potentially simplify things a bit in VM land. Do not need to take the
  page lock to follow page->mapping.

The downsides of this is the performance cost of using RCU. In a simple
creat/unlink microbenchmark, performance drops by about 10% due to inability to
reuse cache-hot slab objects. As iterations increase and RCU freeing starts
kicking over, this increases to about 20%.

In cases where inode lifetimes are longer (ie. many inodes may be allocated
during the average life span of a single inode), a lot of this cache reuse is
not applicable, so the regression caused by this patch is smaller.

The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
however this adds some complexity to list walking and store-free path walking,
so I prefer to implement this at a later date, if it is shown to be a win in
real situations. I haven't found a regression in any non-micro benchmark so I
doubt it will be a problem.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:26 +11:00
Vasiliy Kulikov 3af54c9bd9 ipc: shm: fix information leak to userland
The shmid_ds structure is copied to userland with shm_unused{,2,3}
fields unitialized.  It leads to leaking of contents of kernel stack
memory.

Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-30 08:25:51 -07:00
Al Viro ceefda6931 switch get_sb_ns() users
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:17:03 -04:00
Dan Rosenberg 03145beb45 ipc: initialize structure memory to zero for compat functions
This takes care of leaking uninitialized kernel stack memory to
userspace from non-zeroed fields in structs in compat ipc functions.

Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-27 18:03:13 -07:00
Helge Deller b795218075 ipc/shm.c: add RSS and swap size information to /proc/sysvipc/shm
The kernel currently provides no functionality to analyze the RSS and swap
space usage of each individual sysvipc shared memory segment.

This patch adds this info for each existing shm segment by extending the
output of /proc/sysvipc/shm by two columns for RSS and swap.

Since shmctl(SHM_INFO) already provides a similiar calculation (it
currently sums up all RSS/swap info for all segments), I did split out a
static function which is now used by the /proc/sysvipc/shm output and
shmctl(SHM_INFO).

SAP products (esp.  the SAP Netweaver ABAP Kernel) uses lots of big shared
memory segments (we often have Linux systems with >= 16GB shm usage).
Sometimes we get customer reports about "slow" system responses and while
looking into their configurations we often find massive swapping activity
on the system.  With this patch it's now easy to see from the command line
if and which shm segments gets swapped out (and how much) and can more
easily give recommendations for system tuning.  Without the patch it's
currently not possible to do such shm analysis at all.

Also...

Add some spaces in front of the "size" field for 64bit kernels to get the
columns correct if you cat the contents of the file.  In
sysvipc_shm_proc_show() the kernel prints the size value in "SPEC_SIZE"
format, which is defined like this:

#if BITS_PER_LONG <= 32
#define SIZE_SPEC "%10lu"
#else
#define SIZE_SPEC "%21lu"
#endif

So, if the header is not adjusted, the columns are not correctly aligned.
I actually tested this on 32- and 64-bit and it seems correct now.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: Manfred Spraul <manfred@colorfullife.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-27 18:03:13 -07:00
Christoph Hellwig 85fe4025c6 fs: do not assign default i_ino in new_inode
Instead of always assigning an increasing inode number in new_inode
move the call to assign it into those callers that actually need it.
For now callers that need it is estimated conservatively, that is
the call is added to all filesystems that do not assign an i_ino
by themselves.  For a few more filesystems we can avoid assigning
any inode number given that they aren't user visible, and for others
it could be done lazily when an inode number is actually needed,
but that's left for later patches.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25 21:26:11 -04:00
Al Viro 7de9c6ee3e new helper: ihold()
Clones an existing reference to inode; caller must already hold one.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25 21:26:11 -04:00
Linus Torvalds 092e0e7e52 Merge branch 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl
* 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
  vfs: make no_llseek the default
  vfs: don't use BKL in default_llseek
  llseek: automatically add .llseek fop
  libfs: use generic_file_llseek for simple_attr
  mac80211: disallow seeks in minstrel debug code
  lirc: make chardev nonseekable
  viotape: use noop_llseek
  raw: use explicit llseek file operations
  ibmasmfs: use generic_file_llseek
  spufs: use llseek in all file operations
  arm/omap: use generic_file_llseek in iommu_debug
  lkdtm: use generic_file_llseek in debugfs
  net/wireless: use generic_file_llseek in debugfs
  drm: use noop_llseek
2010-10-22 10:52:56 -07:00
Arnd Bergmann 6038f373a3 llseek: automatically add .llseek fop
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.

The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.

New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time.  Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.

The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.

Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.

Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.

===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
//   but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}

@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}

@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
   *off = E
|
   *off += E
|
   func(..., off, ...)
|
   E = *off
)
...+>
}

@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}

@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
  *off = E
|
  *off += E
|
  func(..., off, ...)
|
  E = *off
)
...+>
}

@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}

@ fops0 @
identifier fops;
@@
struct file_operations fops = {
 ...
};

@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
 .llseek = llseek_f,
...
};

@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
 .read = read_f,
...
};

@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
 .write = write_f,
...
};

@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
 .open = open_f,
...
};

// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
...  .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};

@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
...  .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};

// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
...  .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};

// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};

// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};

@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+	.llseek = default_llseek, /* write accesses f_pos */
};

// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////

@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
 .write = write_f,
 .read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};

@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};

@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};

@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
2010-10-15 15:53:27 +02:00
Dan Rosenberg 982f7c2b2e sys_semctl: fix kernel stack leakage
The semctl syscall has several code paths that lead to the leakage of
uninitialized kernel stack memory (namely the IPC_INFO, SEM_INFO,
IPC_STAT, and SEM_STAT commands) during the use of the older, obsolete
version of the semid_ds struct.

The copy_semid_to_user() function declares a semid_ds struct on the stack
and copies it back to the user without initializing or zeroing the
"sem_base", "sem_pending", "sem_pending_last", and "undo" pointers,
allowing the leakage of 16 bytes of kernel stack memory.

The code is still reachable on 32-bit systems - when calling semctl()
newer glibc's automatically OR the IPC command with the IPC_64 flag, but
invoking the syscall directly allows users to use the older versions of
the struct.

Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-01 10:50:58 -07:00
Al Viro 6d8af64c1c switch mqueue to ->evict_inode()
... and since the inodes are never hashed, we can use default ->drop_inode()
just fine.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09 16:47:58 -04:00
Manfred Spraul c61284e991 ipc/sem.c: bugfix for semop() not reporting successful operation
The last change to improve the scalability moved the actual wake-up out of
the section that is protected by spin_lock(sma->sem_perm.lock).

This means that IN_WAKEUP can be in queue.status even when the spinlock is
acquired by the current task.  Thus the same loop that is performed when
queue.status is read without the spinlock acquired must be performed when
the spinlock is acquired.

Thanks to kamezawa.hiroyu@jp.fujitsu.com for noticing lack of the memory
barrier.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=16255

[akpm@linux-foundation.org: clean up kerneldoc, checkpatch warning and whitespace]
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Reported-by: Luca Tettamanti <kronos.it@gmail.com>
Tested-by: Luca Tettamanti <kronos.it@gmail.com>
Reported-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Maciej Rutecki <maciej.rutecki@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-07-20 16:25:40 -07:00
Al Viro 0abbb609ac mqueue doesn't need make_bad_inode()
It never hashes them anyway and does final iput() immediately
afterwards.  With ->drop_inode() being generic_delete_inode()...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-06-04 17:16:27 -04:00
Christoph Hellwig 7ea8085910 drop unused dentry argument to ->fsync
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-05-27 22:05:02 -04:00
Julia Lawall 4de85cd6d6 ipc/sem.c: use ERR_CAST
Use ERR_CAST(x) rather than ERR_PTR(PTR_ERR(x)).  The former makes more
clear what is the purpose of the operation, which otherwise looks like a
no-op.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
type T;
T x;
identifier f;
@@

T f (...) { <+...
- ERR_PTR(PTR_ERR(x))
+ x
 ...+> }

@@
expression x;
@@

- ERR_PTR(PTR_ERR(x))
+ ERR_CAST(x)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:49 -07:00
Manfred Spraul c5cf6359ad ipc/sem.c: update description of the implementation
ipc/sem.c begins with a 15 year old description about bugs in the initial
implementation in Linux-1.0.  The patch replaces that with a top level
description of the current code.

A TODO could be derived from this text:

The opengroup man page for semop() does not mandate FIFO.  Thus there is
no need for a semaphore array list of pending operations.

If

- this list is removed
- the per-semaphore array spinlock is removed (possible if there is no
  list to protect)
- sem_otime is moved into the semaphores and calculated on demand during
  semctl()

then the array would be read-mostly - which would significantly improve
scaling for applications that use semaphore arrays with lots of entries.

The price would be expensive semctl() calls:

	for(i=0;i<sma->sem_nsems;i++) spin_lock(sma->sem_lock);
	<do stuff>
	for(i=0;i<sma->sem_nsems;i++) spin_unlock(sma->sem_lock);

I'm not sure if the complexity is worth the effort, thus here is the
documentation of the current behavior first.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Zach Brown <zach.brown@oracle.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:49 -07:00
Manfred Spraul 0a2b9d4c79 ipc/sem.c: move wake_up_process out of the spinlock section
The wake-up part of semtimedop() consists out of two steps:

- the right tasks must be identified.
- they must be woken up.

Right now, both steps run while the array spinlock is held.  This patch
reorders the code and moves the actual wake_up_process() behind the point
where the spinlock is dropped.

The code also moves setting sem->sem_otime to one place: It does not make
sense to set the last modify time multiple times.

[akpm@linux-foundation.org: repair kerneldoc]
[akpm@linux-foundation.org: fix uninitialised retval]
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Zach Brown <zach.brown@oracle.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:49 -07:00
Manfred Spraul fd5db42254 ipc/sem.c: optimize update_queue() for bulk wakeup calls
The following series of patches tries to fix the spinlock contention
reported by Chris Mason - his benchmark exposes problems of the current
code:

- In the worst case, the algorithm used by update_queue() is O(N^2).
  Bulk wake-up calls can enter this worst case.  The patch series fix
  that.

  Note that the benchmark app doesn't expose the problem, it just should
  be fixed: Real world apps might do the wake-ups in another order than
  perfect FIFO.

- The part of the code that runs within the semaphore array spinlock is
  significantly larger than necessary.

  The patch series fixes that.  This change is responsible for the main
  improvement.

- The cacheline with the spinlock is also used for a variable that is
  read in the hot path (sem_base) and for a variable that is unnecessarily
  written to multiple times (sem_otime).  The last step of the series
  cacheline-aligns the spinlock.

This patch:

The SysV semaphore code allows to perform multiple operations on all
semaphores in the array as atomic operations.  After a modification,
update_queue() checks which of the waiting tasks can complete.

The algorithm that is used to identify the tasks is O(N^2) in the worst
case.  For some cases, it is simple to avoid the O(N^2).

The patch adds a detection logic for some cases, especially for the case
of an array where all sleeping tasks are single sembuf operations and a
multi-sembuf operation is used to wake up multiple tasks.

A big database application uses that approach.

The patch fixes wakeup due to semctl(,,SETALL,) - the initial version of
the patch breaks that.

[akpm@linux-foundation.org: make do_smart_update() static]
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Zach Brown <zach.brown@oracle.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:49 -07:00
Alexey Dobriyan 4be929be34 kernel-wide: replace USHORT_MAX, SHORT_MAX and SHORT_MIN with USHRT_MAX, SHRT_MAX and SHRT_MIN
- C99 knows about USHRT_MAX/SHRT_MAX/SHRT_MIN, not
  USHORT_MAX/SHORT_MAX/SHORT_MIN.

- Make SHRT_MIN of type s16, not int, for consistency.

[akpm@linux-foundation.org: fix drivers/dma/timb_dma.c]
[akpm@linux-foundation.org: fix security/keys/keyring.c]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:07:02 -07:00
Linus Torvalds 164d44fd92 Merge branch 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  clocksource: Add clocksource_register_hz/khz interface
  posix-cpu-timers: Optimize run_posix_cpu_timers()
  time: Remove xtime_cache
  mqueue: Convert message queue timeout to use hrtimers
  hrtimers: Provide schedule_hrtimeout for CLOCK_REALTIME
  timers: Introduce the concept of timer slack for legacy timers
  ntp: Remove tickadj
  ntp: Make time_adjust static
  time: Add xtime, wall_to_monotonic to feature-removal-schedule
  timer: Try to survive timer callback preempt_count leak
  timer: Split out timer function call
  timer: Print function name for timer callbacks modifying preemption count
  time: Clean up warp_clock()
  cpu-timers: Avoid iterating over all threads in fastpath_timer_check()
  cpu-timers: Change SIGEV_NONE timer implementation
  cpu-timers: Return correct previous timer reload value
  cpu-timers: Cleanup arm_timer()
  cpu-timers: Simplify RLIMIT_CPU handling
2010-05-19 17:11:10 -07:00
André Goddard Rosa a3ed2a1571 mqueue: fix kernel BUG caused by double free() on mq_open()
In case of aborting because we reach the maximum amount of memory which
can be allocated to message queues per user (RLIMIT_MSGQUEUE), we would
try to free the message area twice when bailing out: first by the error
handling code itself, and then later when cleaning up the inode through
delete_inode().

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-11 17:33:42 -07:00
Thomas Gleixner dbb6be6d5e Merge branch 'linus' into timers/core
Reason: Further posix_cpu_timer patches depend on mainline changes

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-05-10 14:20:42 +02:00
Carsten Emde 9ca7d8e683 mqueue: Convert message queue timeout to use hrtimers
The message queue functions mq_timedsend() and mq_timedreceive()
have not yet been converted to use the hrtimer interface.

This patch replaces the call to schedule_timeout() by a call to
schedule_hrtimeout() and transforms the expiration time from
timespec to ktime as required.

[ tglx: Fixed whitespace wreckage ]

Signed-off-by: Carsten Emde <C.Emde@osadl.org>
Tested-by: Pradyumna Sampath <pradysam@gmail.com>
Cc: Arjan van de Veen <arjan@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <20100402204331.715783034@osadl.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-04-06 21:50:03 +02:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Anton Blanchard 45575f5a42 ppc64 sys_ipc breakage in 2.6.34-rc2
I chased down a fail on ppc64 on 2.6.34-rc2 where an application that
uses shared memory was getting a SEGV.

Commit baed7fc9b5 ("Add generic sys_ipc
wrapper") changed the second argument from an unsigned long to an int.
When we call shmget the system call wrappers for sys_ipc will sign
extend second (ie the size) which truncates it.  It took a while to
track down because the call succeeds and strace shows the untruncated
size :)

The patch below changes second from an int to an unsigned long which
fixes shmget on ppc64 (and I assume s390, sparc64 and mips64).

Signed-off-by: Anton Blanchard <anton@samba.org>
--

I assume the function prototypes for the other IPC methods would cause us
to sign or zero extend second where appropriate (avoiding any security
issues). Come to think of it, the syscall wrappers for each method should do
that for us as well.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-22 09:57:19 -07:00
Jiri Slaby f1eb1332b8 ipc: use rlimit helpers
Make sure compiler won't do weird things with limits.  E.g.  fetching them
twice may return 2 different values after writable limits are implemented.

I.e.  either use rlimit helpers added in
3e10e716ab ("resource: add helpers for
fetching rlimits") or ACCESS_ONCE if not applicable.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:39 -08:00
Christoph Hellwig baed7fc9b5 Add generic sys_ipc wrapper
Add a generic implementation of the ipc demultiplexer syscall.  Except for
s390 and sparc64 all implementations of the sys_ipc are nearly identical.

There are slight differences in the types of the parameters, where mips
and powerpc as the only 64-bit architectures with sys_ipc use unsigned
long for the "third" argument as it gets casted to a pointer later, while
it traditionally is an "int" like most other paramters.  frv goes even
further and uses unsigned long for all parameters execept for "ptr" which
is a pointer type everywhere.  The change from int to unsigned long for
"third" and back to "int" for the others on frv should be fine due to the
in-register calling conventions for syscalls (we already had a similar
issue with the generic sys_ptrace), but I'd prefer to have the arch
maintainers looks over this in details.

Except for that h8300, m68k and m68knommu lack an impplementation of the
semtimedop sub call which this patch adds, and various architectures have
gets used - at least on i386 it seems superflous as the compat code on
x86-64 and ia64 doesn't even bother to implement it.

[akpm@linux-foundation.org: add sys_ipc to sys_ni.c]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Reviewed-by: H. Peter Anvin <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-12 15:52:32 -08:00
André Goddard Rosa 2329e392ac mqueue: fix typo "failues" -> "failures"
Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03 14:48:00 -05:00
André Goddard Rosa 8d8ffefaaf mqueue: only set error codes if they are really necessary
... postponing assignments until they're needed. Doesn't change code size.

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03 14:48:00 -05:00
André Goddard Rosa 04db0dde0e mqueue: simplify do_open() error handling
It reduces code size:
text    data     bss     dec     hex filename
9925      72      16   10013    271d ipc/mqueue-BEFORE.o
9885      72      16    9973    26f5 ipc/mqueue-AFTER.o

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03 14:48:00 -05:00
André Goddard Rosa 8834cf796a mqueue: apply mathematics distributivity on mq_bytes calculation
Code size reduction:
   text    data     bss     dec     hex filename
   9941      72      16   10029    272d ipc/mqueue-BEFORE.o
   9925      72      16   10013    271d ipc/mqueue-AFTER.o

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03 14:48:00 -05:00
André Goddard Rosa c8308b1c91 mqueue: remove unneeded info->messages initialization
... and abort earlier if we couldn't allocate the message pointers array,
avoiding the u->mq_bytes accounting logic.

It reduces code size:
   text    data     bss     dec     hex filename
   9949      72      16   10037    2735 ipc/mqueue-BEFORE.o
   9941      72      16   10029    272d ipc/mqueue-AFTER.o

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03 14:47:59 -05:00
André Goddard Rosa 4294a8eedb mqueue: fix mq_open() file descriptor leak on user-space processes
We leak fd on lookup_one_len() failure

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03 14:46:05 -05:00
David Howells ed5e5894b2 nommu: fix SYSV SHM for NOMMU
Commit c4caa77815 ("file
->get_unmapped_area() shouldn't duplicate work of get_unmapped_area()")
broke SYSV SHM for NOMMU by taking away the pointer to
shm_get_unmapped_area() from shm_file_operations.

Put it back conditionally on CONFIG_MMU=n.

file->f_ops->get_unmapped_area() is used to find out the base address for a
mapping of a mappable chardev device or mappable memory-based file (such as a
ramfs file).  It needs to be called prior to file->f_ops->mmap() being called.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Greg Ungerer <gerg@snapgear.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-16 12:15:39 -08:00
Linus Torvalds bac5e54c29 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (38 commits)
  direct I/O fallback sync simplification
  ocfs: stop using do_sync_mapping_range
  cleanup blockdev_direct_IO locking
  make generic_acl slightly more generic
  sanitize xattr handler prototypes
  libfs: move EXPORT_SYMBOL for d_alloc_name
  vfs: force reval of target when following LAST_BIND symlinks (try #7)
  ima: limit imbalance msg
  Untangling ima mess, part 3: kill dead code in ima
  Untangling ima mess, part 2: deal with counters
  Untangling ima mess, part 1: alloc_file()
  O_TRUNC open shouldn't fail after file truncation
  ima: call ima_inode_free ima_inode_free
  IMA: clean up the IMA counts updating code
  ima: only insert at inode creation time
  ima: valid return code from ima_inode_alloc
  fs: move get_empty_filp() deffinition to internal.h
  Sanitize exec_permission_lite()
  Kill cached_lookup() and real_lookup()
  Kill path_lookup_open()
  ...

Trivial conflicts in fs/direct-io.c
2009-12-16 12:04:02 -08:00
Al Viro b65a9cfc2c Untangling ima mess, part 2: deal with counters
* do ima_get_count() in __dentry_open()
* stop doing that in followups
* move ima_path_check() to right after nameidata_to_filp()
* don't bump counters on it

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16 12:16:47 -05:00
Al Viro 0552f879d4 Untangling ima mess, part 1: alloc_file()
There are 2 groups of alloc_file() callers:
	* ones that are followed by ima_counts_get
	* ones giving non-regular files
So let's pull that ima_counts_get() into alloc_file();
it's a no-op in case of non-regular files.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16 12:16:47 -05:00
Al Viro 2c48b9c455 switch alloc_file() to passing struct path
... and have the caller grab both mnt and dentry; kill
leak in infiniband, while we are at it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16 12:16:42 -05:00
Amerigo Wang e5cc9c7b1a ipc: remove unreachable code in sem.c
This line is unreachable, remove it.

[akpm@linux-foundation.org: remove unneeded initialisation of `err']
Signed-off-by: WANG Cong <amwang@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16 07:20:10 -08:00
Manfred Spraul d987f8b213 ipc/sem.c: optimize single sops when semval is zero
If multiple simple decrements on the same semaphore are pending, then the
current code scans all decrement operations, even if the semaphore value
is already 0.

The patch optimizes that: if the semaphore value is 0, then there is no
need to scan the q->alter entries.

Note that this is a common case: It happens if 100 decrements by one are
pending and now an increment by one increases the semaphore value from 0
to 1.  Without this patch, all 100 entries are scanned.  With the patch,
only one entry is scanned, then woken up.  Then the new rule triggers and
the scanning is aborted, without looking at the remaining 99 tasks.

With this patch, single sop increment/decrement by 1 are now O(1).
(same as with Nick's patch)

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16 07:20:10 -08:00
Manfred Spraul 636c6be823 ipc/sem.c: optimize single semop operations
sysv sem has the concept of semaphore arrays that consist out of multiple
semaphores.  Atomic operations that affect multiple semaphores are
supported.

The patch optimizes single semaphore operation calls that affect only one
semaphore: It's not necessary to scan all pending operations, it is
sufficient to scan the per-semaphore list.

The idea is from Nick Piggin version of an ipc sem improvement, the
implementation is different: The code tries to keep as much common code as
possible.

As the result, the patch is simpler, but optimizes fewer cases.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16 07:20:10 -08:00
Manfred Spraul b97e820fff ipc/sem.c: add a per-semaphore pending list
Based on Nick's findings:

sysv sem has the concept of semaphore arrays that consist out of multiple
semaphores.  Atomic operations that affect multiple semaphores are
supported.

The patch is the first step for optimizing simple, single semaphore
operations: In addition to the global list of all pending operations, a
2nd, per-semaphore list with the simple operations is added.

Note: this patch does not make sense by itself, the new list is used
nowhere.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16 07:20:10 -08:00
Manfred Spraul b6e90822e7 ipc/sem.c: optimize if semops fail
Reduce the amount of scanning of the list of pending semaphore operations:
If try_atomic_semop failed, then no changes were applied.  Thus no need to
restart.

Additionally, this patch correct an incorrect comment: It's possible to
wait for arbitrary semaphore values (do a dec by <x>, wait-for-zero, inc
by <x> in one atomic operation)

Both changes are from Nick Piggin, the patch is the result of a different
split of the individual changes.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16 07:20:09 -08:00
Nick Piggin d4212093dc ipc/sem.c: sem preempt improve
The strange sysv semaphore wakeup scheme has a kind of busy-wait lock
involved, which could deadlock if preemption is enabled during the "lock".

It is an implementation detail (due to a spinlock being held) that this is
actually the case.  However if "spinlocks" are made preemptible, or if the
sem lock is changed to a sleeping lock for example, then the wakeup would
become buggy.  So this might be a bugfix for -rt kernels.

Imagine waker being preempted by wakee and never clearing IN_WAKEUP -- if
wakee has higher RT priority then there is a priority inversion deadlock.
Even if there is not a priority inversion to cause a deadlock, then there
is still time wasted spinning.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16 07:20:09 -08:00
Nick Piggin 9cad200c76 ipc/sem.c: sem use list operations
Replace the handcoded list operations in update_queue() with the standard
list_for_each_entry macros.

list_for_each_entry_safe() must be used, because list entries can
disappear immediately uppon the wakeup event.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16 07:20:09 -08:00
Nick Piggin bf17bb7177 ipc/sem.c: sem optimise undo list search
Around a month ago, there was some discussion about an improvement of the
sysv sem algorithm: Most (at least: some important) users only use simple
semaphore operations, therefore it's worthwile to optimize this use case.

This patch:

Move last looked up sem_undo struct to the head of the task's undo list.
Attempt to move common entries to the front of the list so search time is
reduced.  This reduces lookup_undo on oprofile of problematic SAP workload
by 30% (see patch 4 for a description of SAP workload).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16 07:20:09 -08:00
Serge E. Hallyn 7d6feeb287 ipc ns: fix memory leak (idr)
We have apparently had a memory leak since
7ca7e564e0 "ipc: store ipcs into IDRs" in
2007.  The idr of which 3 exist for each ipc namespace is never freed.

This patch simply frees them when the ipcns is freed.  I don't believe any
idr_remove() are done from rcu (and could therefore be delayed until after
this idr_destroy()), so the patch should be safe.  Some quick testing
showed no harm, and the memory leak fixed.

Caught by kmemleak.

Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16 07:20:09 -08:00
Al Viro c4caa77815 file ->get_unmapped_area() shouldn't duplicate work of get_unmapped_area()
... we should call mm ->get_unmapped_area() instead and let our caller
do the final checks.

Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-11 06:34:09 -05:00
Linus Torvalds 4ef58d4e2a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (42 commits)
  tree-wide: fix misspelling of "definition" in comments
  reiserfs: fix misspelling of "journaled"
  doc: Fix a typo in slub.txt.
  inotify: remove superfluous return code check
  hdlc: spelling fix in find_pvc() comment
  doc: fix regulator docs cut-and-pasteism
  mtd: Fix comment in Kconfig
  doc: Fix IRQ chip docs
  tree-wide: fix assorted typos all over the place
  drivers/ata/libata-sff.c: comment spelling fixes
  fix typos/grammos in Documentation/edac.txt
  sysctl: add missing comments
  fs/debugfs/inode.c: fix comment typos
  sgivwfb: Make use of ARRAY_SIZE.
  sky2: fix sky2_link_down copy/paste comment error
  tree-wide: fix typos "couter" -> "counter"
  tree-wide: fix typos "offest" -> "offset"
  fix kerneldoc for set_irq_msi()
  spidev: fix double "of of" in comment
  comment typo fix: sybsystem -> subsystem
  ...
2009-12-09 19:43:33 -08:00
Felipe Contreras f1970c48ef ipc: fix unused variable warning
Commit a0d092f introduced the following warning:
ipc/msg.c: In function ?msgctl_down?:
ipc/msg.c:415: warning: ?msqid64? may be used uninitialized in this function

The gcc warning in this case is actually bogus, as msqid64 is touched only
iff cmd == IPC_SET, and in such case, copy_msqid_from_user() initializes
it properly.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-12-04 15:39:49 +01:00
Eric W. Biederman 2bc4657c15 sysctl ipc: Remove dead binary sysctl support code.
Now that sys_sysctl is a generic wrapper around /proc/sys  .ctl_name
and .strategy members of sysctl tables are dead code.  Remove them.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2009-11-12 02:04:54 -08:00
Alexey Dobriyan f0f37e2f77 const: mark struct vm_struct_operations
* mark struct vm_area_struct::vm_ops as const
* mark vm_ops in AGP code

But leave TTM code alone, something is fishy there with global vm_ops
being used.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-27 11:39:25 -07:00
Alexey Dobriyan 8d65af789f sysctl: remove "struct file *" argument of ->proc_handler
It's unused.

It isn't needed -- read or write flag is already passed and sysctl
shouldn't care about the rest.

It _was_ used in two places at arch/frv for some reason.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:04 -07:00
James Morris 88e9d34c72 seq_file: constify seq_operations
Make all seq_operations structs const, to help mitigate against
revectoring user-triggerable function pointers.

This is derived from the grsecurity patch, although generated from scratch
because it's simpler than extracting the changes from there.

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-23 07:39:29 -07:00
Eric B Munson 6bfde05bf5 hugetlbfs: allow the creation of files suitable for MAP_PRIVATE on the vfs internal mount
This patchset adds a flag to mmap that allows the user to request that an
anonymous mapping be backed with huge pages.  This mapping will borrow
functionality from the huge page shm code to create a file on the kernel
internal mount and use it to approximate an anonymous mapping.  The
MAP_HUGETLB flag is a modifier to MAP_ANONYMOUS and will not work without
both flags being preset.

A new flag is necessary because there is no other way to hook into huge
pages without creating a file on a hugetlbfs mount which wouldn't be
MAP_ANONYMOUS.

To userspace, this mapping will behave just like an anonymous mapping
because the file is not accessible outside of the kernel.

This patchset is meant to simplify the programming model.  Presently there
is a large chunk of boiler platecode, contained in libhugetlbfs, required
to create private, hugepage backed mappings.  This patch set would allow
use of hugepages without linking to libhugetlbfs or having hugetblfs
mounted.

Unification of the VM code would provide these same benefits, but it has
been resisted each time that it has been suggested for several reasons: it
would break PAGE_SIZE assumptions across the kernel, it makes page-table
abstractions really expensive, and it does not provide any benefit on
architectures that do not support huge pages, incurring fast path
penalties without providing any benefit on these architectures.

This patch:

There are two means of creating mappings backed by huge pages:

        1. mmap() a file created on hugetlbfs
        2. Use shm which creates a file on an internal mount which essentially
           maps it MAP_SHARED

The internal mount is only used for shared mappings but there is very
little that stops it being used for private mappings. This patch extends
hugetlbfs_file_setup() to deal with the creation of files that will be
mapped MAP_PRIVATE on the internal hugetlbfs mount. This extended API is
used in a subsequent patch to implement the MAP_HUGETLB mmap() flag.

Signed-off-by: Eric Munson <ebmunson@us.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Adam Litke <agl@us.ibm.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:41 -07:00
Alexey Dobriyan b87221de6a const: mark remaining super_operations const
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:24 -07:00
Hugh Dickins 2195d2818c fix undefined reference to user_shm_unlock
My 353d5c30c6 "mm: fix hugetlb bug due to
user_shm_unlock call" broke the CONFIG_SYSVIPC !CONFIG_MMU build of both
2.6.31 and 2.6.30.6: "undefined reference to `user_shm_unlock'".

gcc didn't understand my comment! so couldn't figure out to optimize
away user_shm_unlock() from the error path in the hugetlb-less case, as
it does elsewhere.  Help it to do so, in a language it understands.

Reported-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-14 17:45:31 -07:00
Hugh Dickins 353d5c30c6 mm: fix hugetlb bug due to user_shm_unlock call
2.6.30's commit 8a0bdec194 removed
user_shm_lock() calls in hugetlb_file_setup() but left the
user_shm_unlock call in shm_destroy().

In detail:
Assume that can_do_hugetlb_shm() returns true and hence user_shm_lock()
is not called in hugetlb_file_setup(). However, user_shm_unlock() is
called in any case in shm_destroy() and in the following
atomic_dec_and_lock(&up->__count) in free_uid() is executed and if
up->__count gets zero, also cleanup_user_struct() is scheduled.

Note that sched_destroy_user() is empty if CONFIG_USER_SCHED is not set.
However, the ref counter up->__count gets unexpectedly non-positive and
the corresponding structs are freed even though there are live
references to them, resulting in a kernel oops after a lots of
shmget(SHM_HUGETLB)/shmctl(IPC_RMID) cycles and CONFIG_USER_SCHED set.

Hugh changed Stefan's suggested patch: can_do_hugetlb_shm() at the
time of shm_destroy() may give a different answer from at the time
of hugetlb_file_setup().  And fixed newseg()'s no_id error path,
which has missed user_shm_unlock() ever since it came in 2.6.9.

Reported-by: Stefan Huber <shuber2@gmail.com>
Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Tested-by: Stefan Huber <shuber2@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-24 12:53:01 -07:00
Mimi Zohar 46690f3718 integrity: ima mq_open imbalance msg fix
This patch fixes an imbalance message as reported by Sanchin Sant.
As we don't need to measure the message queue, just increment the
counters.

Reported-by: Sanchin Sant <sanchinp@in.ibm.com>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-06-29 08:56:46 +10:00
Johannes Weiner 232086b199 ipc: unbreak 32-bit shmctl/semctl/msgctl
31a985f "ipc: use __ARCH_WANT_IPC_PARSE_VERSION in ipc/util.h" would
choose the implementation of ipc_parse_version() based on a symbol
defined in <asm/unistd.h>.

But it failed to also include this header and thus broke
IPC_64-passing 32-bit userspace because the flag wasn't masked out
properly anymore and the command not understood.

Include <linux/unistd.h> to give the architecture a chance to ask for
the no-no-op ipc_parse_version().

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-21 12:48:43 -07:00
Alexey Dobriyan 665c7741fb ipcns: move free_ipcs() proto
Function is really private to ipc/ and avoid struct kern_ipc_perm
forward declaration.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18 13:03:56 -07:00
Alexey Dobriyan b4188def44 ipcns: make free_ipc_ns() static
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18 13:03:56 -07:00
Alexey Dobriyan 612ce478fa ipcns: extract create_ipc_ns()
clone_ipc_ns() is misnamed, it doesn't clone anything and doesn't use
passed parameter.  Rename it.

create_ipc_ns() will be used by C/R to create fresh ipcns.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18 13:03:55 -07:00
Alexey Dobriyan 64424289dd ipcns: remove useless get/put while CLONE_NEWIPC
copy_ipcs() doesn't actually copy anything. If new ipcns is created, it's
created from scratch, in this case get/put on old ipcns isn't needed.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18 13:03:55 -07:00
Arnd Bergmann 31a985fbb1 ipc: use __ARCH_WANT_IPC_PARSE_VERSION in ipc/util.h
The definition of ipc_parse_version depends on
__ARCH_WANT_IPC_PARSE_VERSION, but the header file declares it
conditionally based on the architecture.

Use the macro consistently to make it easier to add new architectures.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18 13:03:54 -07:00
Linus Torvalds 3296ca27f5 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: (44 commits)
  nommu: Provide mmap_min_addr definition.
  TOMOYO: Add description of lists and structures.
  TOMOYO: Remove unused field.
  integrity: ima audit dentry_open failure
  TOMOYO: Remove unused parameter.
  security: use mmap_min_addr indepedently of security models
  TOMOYO: Simplify policy reader.
  TOMOYO: Remove redundant markers.
  SELinux: define audit permissions for audit tree netlink messages
  TOMOYO: Remove unused mutex.
  tomoyo: avoid get+put of task_struct
  smack: Remove redundant initialization.
  integrity: nfsd imbalance bug fix
  rootplug: Remove redundant initialization.
  smack: do not beyond ARRAY_SIZE of data
  integrity: move ima_counts_get
  integrity: path_check update
  IMA: Add __init notation to ima functions
  IMA: Minimal IMA policy and boot param for TCB IMA policy
  selinux: remove obsolete read buffer limit from sel_read_bool
  ...
2009-06-11 10:01:41 -07:00
Linus Torvalds 20f3f3ca49 Merge branch 'rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rcu: rcu_sched_grace_period(): kill the bogus flush_signals()
  rculist: use list_entry_rcu in places where it's appropriate
  rculist.h: introduce list_entry_rcu() and list_first_entry_rcu()
  rcu: Update RCU tracing documentation for __rcu_pending
  rcu: Add __rcu_pending tracing to hierarchical RCU
  RCU: make treercu be default
2009-06-10 19:50:03 -07:00
James Morris 73fbad283c Merge branch 'next' into for-linus 2009-06-11 11:03:14 +10:00
Mike Frysinger 586c7e6a28 shm: fix unused warnings on nommu
The massive nommu update (8feae131) resulted in these warnings:
ipc/shm.c: In function `sys_shmdt':
ipc/shm.c:974: warning: unused variable `size'
ipc/shm.c:972: warning: unused variable `next'

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-09 16:59:03 -07:00
Mimi Zohar c9d9ac525a integrity: move ima_counts_get
Based on discussion on lkml (Andrew Morton and Eric Paris),
move ima_counts_get down a layer into shmem/hugetlb__file_setup().
Resolves drm shmem_file_setup() usage case as well.

HD comment:
  I still think you're doing this at the wrong level, but recognize
  that you probably won't be persuaded until a few more users of
  alloc_file() emerge, all wanting your ima_counts_get().

  Resolving GEM's shmem_file_setup() is an improvement, so I'll say

Acked-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-05-22 09:45:33 +10:00
Mimi Zohar b9fc745db8 integrity: path_check update
- Add support in ima_path_check() for integrity checking without
incrementing the counts. (Required for nfsd.)
- rename and export opencount_get to ima_counts_get
- replace ima_shm_check calls with ima_counts_get
- export ima_path_check

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-05-22 09:43:41 +10:00
Jiri Pirko 05725f7eb4 rculist: use list_entry_rcu in places where it's appropriate
Use previously introduced list_entry_rcu instead of an open-coded
list_entry + rcu_dereference combination.

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: dipankar@in.ibm.com
LKML-Reference: <20090414181715.GA3634@psychotron.englab.brq.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-15 12:05:25 +02:00
Geert Uytterhoeven f26ec5baa6 namespaces: move get_mq() inside #ifdef CONFIG_SYSCTL
| ipc/mq_sysctl.c:26: warning: 'get_mq' defined but not used

Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-13 15:04:29 -07:00
Serge E. Hallyn bdc8e5f85f namespaces: mqueue namespace: adapt sysctl
Largely inspired from ipc/ipc_sysctl.c.  This patch isolates the mqueue
sysctl stuff in its own file.

[akpm@linux-foundation.org: build fix]
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 08:31:09 -07:00
Serge E. Hallyn 7eafd7c74c namespaces: ipc namespaces: implement support for posix msqueues
Implement multiple mounts of the mqueue file system, and link it to usage
of CLONE_NEWIPC.

Each ipc ns has a corresponding mqueuefs superblock.  When a user does
clone(CLONE_NEWIPC) or unshare(CLONE_NEWIPC), the unshare will cause an
internal mount of a new mqueuefs sb linked to the new ipc ns.

When a user does 'mount -t mqueue mqueue /dev/mqueue', he mounts the
mqueuefs superblock.

Posix message queues can be worked with both through the mq_* system calls
(see mq_overview(7)), and through the VFS through the mqueue mount.  Any
usage of mq_open() and friends will work with the acting task's ipc
namespace.  Any actions through the VFS will work with the mqueuefs in
which the file was created.  So if a user doesn't remount mqueuefs after
unshare(CLONE_NEWIPC), mq_open("/ab") will not be reflected in "ls
/dev/mqueue".

If task a mounts mqueue for ipc_ns:1, then clones task b with a new ipcns,
ipcns:2, and then task a is the last task in ipc_ns:1 to exit, then (1)
ipc_ns:1 will be freed, (2) it's superblock will live on until task b
umounts the corresponding mqueuefs, and vfs actions will continue to
succeed, but (3) sb->s_fs_info will be NULL for the sb corresponding to
the deceased ipc_ns:1.

To make this happen, we must protect the ipc reference count when

a) a task exits and drops its ipcns->count, since it might be dropping
   it to 0 and freeing the ipcns

b) a task accesses the ipcns through its mqueuefs interface, since it
   bumps the ipcns refcount and might race with the last task in the ipcns
   exiting.

So the kref is changed to an atomic_t so we can use
atomic_dec_and_lock(&ns->count,mq_lock), and every access to the ipcns
through ns = mqueuefs_sb->s_fs_info is protected by the same lock.

Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 08:31:09 -07:00
Serge E. Hallyn 614b84cf4e namespaces: mqueue ns: move mqueue_mnt into struct ipc_namespace
Move mqueue vfsmount plus a few tunables into the ipc_namespace struct.
The CONFIG_IPC_NS boolean and the ipc_namespace struct will serve both the
posix message queue namespaces and the SYSV ipc namespaces.

The sysctl code will be fixed separately in patch 3.  After just this
patch, making a change to posix mqueue tunables always changes the values
in the initial ipc namespace.

Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07 08:31:09 -07:00
Linus Torvalds 8fe74cf053 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  Remove two unneeded exports and make two symbols static in fs/mpage.c
  Cleanup after commit 585d3bc06f
  Trim includes of fdtable.h
  Don't crap into descriptor table in binfmt_som
  Trim includes in binfmt_elf
  Don't mess with descriptor table in load_elf_binary()
  Get rid of indirect include of fs_struct.h
  New helper - current_umask()
  check_unsafe_exec() doesn't care about signal handlers sharing
  New locking/refcounting for fs_struct
  Take fs_struct handling to new file (fs/fs_struct.c)
  Get rid of bumping fs_struct refcount in pivot_root(2)
  Kill unsharing fs_struct in __set_personality()
2009-04-02 21:09:10 -07:00
Serge E. Hallyn 11dea19009 proc_sysctl: use CONFIG_PROC_SYSCTL around ipc and utsname proc_handlers
As pointed out by Cedric Le Goater (in response to Alexey's original
comment wrt mqns), ipc_sysctl.c and utsname_sysctl.c are using
CONFIG_PROC_FS, not CONFIG_PROC_SYSCTL, to determine whether to define
the proc_handlers.  Change that.

Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Acked-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02 19:05:01 -07:00
Tony Battersby e562aebc6c ipc: make shm_get_stat() more robust
shm_get_stat() assumes idr_find(&shm_ids(ns).ipcs_idr) returns "struct
shmid_kernel *"; all other callers assume that it returns "struct
kern_ipc_perm *".  This works because "struct kern_ipc_perm" is currently
the first member of "struct shmid_kernel", but it would be better to use
container_of() to prevent future breakage.

Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Cc: Jiri Olsa <olsajiri@gmail.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02 19:05:01 -07:00
Al Viro ce3b0f8d5c New helper - current_umask()
current->fs->umask is what most of fs_struct users are doing.
Put that into a helper function.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-31 23:00:26 -04:00
Linus Torvalds 8e9d208972 Merge branch 'bkl-removal' of git://git.lwn.net/linux-2.6
* 'bkl-removal' of git://git.lwn.net/linux-2.6:
  Rationalize fasync return values
  Move FASYNC bit handling to f_op->fasync()
  Use f_lock to protect f_flags
  Rename struct file->f_ep_lock
2009-03-26 16:14:02 -07:00
James Morris 703a3cd728 Merge branch 'master' into next 2009-03-24 10:52:46 +11:00
Jonathan Corbet db1dd4d376 Use f_lock to protect f_flags
Traditionally, changes to struct file->f_flags have been done under BKL
protection, or with no protection at all.  This patch causes all f_flags
changes after file open/creation time to be done under protection of
f_lock.  This allows the removal of some BKL usage and fixes a number of
longstanding (if microscopic) races.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2009-03-16 08:32:27 -06:00
Mel Gorman 5a6fe12595 Do not account for the address space used by hugetlbfs using VM_ACCOUNT
When overcommit is disabled, the core VM accounts for pages used by anonymous
shared, private mappings and special mappings. It keeps track of VMAs that
should be accounted for with VM_ACCOUNT and VMAs that never had a reserve
with VM_NORESERVE.

Overcommit for hugetlbfs is much riskier than overcommit for base pages
due to contiguity requirements. It avoids overcommiting on both shared and
private mappings using reservation counters that are checked and updated
during mmap(). This ensures (within limits) that hugepages exist in the
future when faults occurs or it is too easy to applications to be SIGKILLed.

As hugetlbfs makes its own reservations of a different unit to the base page
size, VM_ACCOUNT should never be set. Even if the units were correct, we would
double account for the usage in the core VM and hugetlbfs. VM_NORESERVE may
be set because an application can request no reserves be made for hugetlbfs
at the risk of getting killed later.

With commit fc8744adc8, VM_NORESERVE and
VM_ACCOUNT are getting unconditionally set for hugetlbfs-backed mappings. This
breaks the accounting for both the core VM and hugetlbfs, can trigger an
OOM storm when hugepage pools are too small lockups and corrupted counters
otherwise are used. This patch brings hugetlbfs more in line with how the
core VM treats VM_NORESERVE but prevents VM_ACCOUNT being set.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-10 10:48:42 -08:00
James Morris cb5629b10d Merge branch 'master' into next
Conflicts:
	fs/namei.c

Manually merged per:

diff --cc fs/namei.c
index 734f2b5,bbc15c2..0000000
--- a/fs/namei.c
+++ b/fs/namei.c
@@@ -860,9 -848,8 +849,10 @@@ static int __link_path_walk(const char
  		nd->flags |= LOOKUP_CONTINUE;
  		err = exec_permission_lite(inode);
  		if (err == -EAGAIN)
- 			err = vfs_permission(nd, MAY_EXEC);
+ 			err = inode_permission(nd->path.dentry->d_inode,
+ 					       MAY_EXEC);
 +		if (!err)
 +			err = ima_path_check(&nd->path, MAY_EXEC);
   		if (err)
  			break;

@@@ -1525,14 -1506,9 +1509,14 @@@ int may_open(struct path *path, int acc
  		flag &= ~O_TRUNC;
  	}

- 	error = vfs_permission(nd, acc_mode);
+ 	error = inode_permission(inode, acc_mode);
  	if (error)
  		return error;
 +
- 	error = ima_path_check(&nd->path,
++	error = ima_path_check(path,
 +			       acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC));
 +	if (error)
 +		return error;
  	/*
  	 * An append-only file must be opened in append mode for writing.
  	 */

Signed-off-by: James Morris <jmorris@namei.org>
2009-02-06 11:01:45 +11:00
Mimi Zohar 1df9f0a731 Integrity: IMA file free imbalance
The number of calls to ima_path_check()/ima_file_free()
should be balanced.  An extra call to fput(), indicates
the file could have been accessed without first being
measured.

Although f_count is incremented/decremented in places other
than fget/fput, like fget_light/fput_light and get_file, the
current task must already hold a file refcnt.  The call to
__fput() is delayed until the refcnt becomes 0, resulting
in ima_file_free() flagging any changes.

- add hook to increment opencount for IPC shared memory(SYSV),
  shmat files, and /dev/zero
- moved NULL iint test in opencount_get()

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-02-06 09:05:33 +11:00
Tony Battersby a68e61e8ff shm: fix shmctl(SHM_INFO) lockup with !CONFIG_SHMEM
shm_get_stat() assumes that the inode is a "struct shmem_inode_info",
which is incorrect for !CONFIG_SHMEM (see fs/ramfs/inode.c:
ramfs_get_inode() vs.  mm/shmem.c: shmem_get_inode()).

This bad assumption can cause shmctl(SHM_INFO) to lockup when
shm_get_stat() tries to spin_lock(&info->lock).  Users of !CONFIG_SHMEM
may encounter this lockup simply by invoking the 'ipcs' command.

Reported by Jiri Olsa back in February 2008:
http://lkml.org/lkml/2008/2/29/74

Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Reported-by: Jiri Olsa <olsajiri@gmail.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: <stable@kernel.org>		[2.6.everything]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-05 12:56:47 -08:00
Linus Torvalds fc8744adc8 Stop playing silly games with the VM_ACCOUNT flag
The mmap_region() code would temporarily set the VM_ACCOUNT flag for
anonymous shared mappings just to inform shmem_zero_setup() that it
should enable accounting for the resulting shm object.  It would then
clear the flag after calling ->mmap (for the /dev/zero case) or doing
shmem_zero_setup() (for the MAP_ANON case).

This just resulted in vma merge issues, but also made for just
unnecessary confusion.  Use the already-existing VM_NORESERVE flag for
this instead, and let shmem_{zero|file}_setup() just figure it out from
that.

This also happens to make it obvious that the new DRI2 GEM layer uses a
non-reserving backing store for its object allocation - which is quite
possibly not intentional.  But since I didn't want to change semantics
in this patch, I left it alone, and just updated the caller to use the
new flag semantics.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-31 15:08:56 -08:00
Heiko Carstens c4ea37c26a [CVE-2009-0029] System call wrappers part 26
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2009-01-14 14:15:29 +01:00
Heiko Carstens d5460c9974 [CVE-2009-0029] System call wrappers part 25
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2009-01-14 14:15:28 +01:00
Heiko Carstens e48fbb699f [CVE-2009-0029] System call wrappers part 24
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2009-01-14 14:15:28 +01:00
Heiko Carstens 6673e0c3fb [CVE-2009-0029] System call wrapper special cases
System calls with an unsigned long long argument can't be converted with
the standard wrappers since that would include a cast to long, which in
turn means that we would lose the upper 32 bit on 32 bit architectures.
Also semctl can't use the standard wrapper since it has a 'union'
parameter.

So we handle them as special case and add some extra wrappers instead.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2009-01-14 14:15:18 +01:00
Heiko Carstens 2ed7c03ec1 [CVE-2009-0029] Convert all system calls to return a long
Convert all system calls to return a long. This should be a NOP since all
converted types should have the same size anyway.
With the exception of sys_exit_group which returned void. But that doesn't
matter since the system call doesn't return.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2009-01-14 14:15:14 +01:00
Linus Torvalds c40f6f8bbc Merge git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-nommu
* git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-nommu:
  NOMMU: Support XIP on initramfs
  NOMMU: Teach kobjsize() about VMA regions.
  FLAT: Don't attempt to expand the userspace stack to fill the space allocated
  FDPIC: Don't attempt to expand the userspace stack to fill the space allocated
  NOMMU: Improve procfs output using per-MM VMAs
  NOMMU: Make mmap allocation page trimming behaviour configurable.
  NOMMU: Make VMAs per MM as for MMU-mode linux
  NOMMU: Delete askedalloc and realalloc variables
  NOMMU: Rename ARM's struct vm_region
  NOMMU: Fix cleanup handling in ramfs_nommu_get_umapped_area()
2009-01-09 14:00:58 -08:00
Sukadev Bhattiprolu a6684999f7 mqueue: fix si_pid value in mqueue do_notify()
If a process registers for asynchronous notification on a POSIX message
queue, it gets a signal and a siginfo_t structure when a message arrives
on the message queue.  The si_pid in the siginfo_t structure is set to the
PID of the process that sent the message to the message queue.

The principle is the following:
. when mq_notify(SIGEV_SIGNAL) is called, the caller registers for
  notification when a msg arrives. The associated pid structure is stroed into
  inode_info->notify_owner. Let's call this process P1.
. when mq_send() is called by say P2, P2 sends a signal to P1 to notify
  him about msg arrival.

The way .si_pid is set today is not correct, since it doesn't take into account
the fact that the process that is sending the message might not be in the
same namespace as the notified one.

This patch proposes to set si_pid to the sender's pid into the notify_owner
namespace.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Bastian Blank <bastian@waldi.eu.org>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-08 08:31:12 -08:00
David Howells 8feae13110 NOMMU: Make VMAs per MM as for MMU-mode linux
Make VMAs per mm_struct as for MMU-mode linux.  This solves two problems:

 (1) In SYSV SHM where nattch for a segment does not reflect the number of
     shmat's (and forks) done.

 (2) In mmap() where the VMA's vm_mm is set to point to the parent mm by an
     exec'ing process when VM_EXECUTABLE is specified, regardless of the fact
     that a VMA might be shared and already have its vm_mm assigned to another
     process or a dead process.

A new struct (vm_region) is introduced to track a mapped region and to remember
the circumstances under which it may be shared and the vm_list_struct structure
is discarded as it's no longer required.

This patch makes the following additional changes:

 (1) Regions are now allocated with alloc_pages() rather than kmalloc() and
     with no recourse to __GFP_COMP, so the pages are not composite.  Instead,
     each page has a reference on it held by the region.  Anything else that is
     interested in such a page will have to get a reference on it to retain it.
     When the pages are released due to unmapping, each page is passed to
     put_page() and will be freed when the page usage count reaches zero.

 (2) Excess pages are trimmed after an allocation as the allocation must be
     made as a power-of-2 quantity of pages.

 (3) VMAs are added to the parent MM's R/B tree and mmap lists.  As an MM may
     end up with overlapping VMAs within the tree, the VMA struct address is
     appended to the sort key.

 (4) Non-anonymous VMAs are now added to the backing inode's prio list.

 (5) Holes may be punched in anonymous VMAs with munmap(), releasing parts of
     the backing region.  The VMA and region structs will be split if
     necessary.

 (6) sys_shmdt() only releases one attachment to a SYSV IPC shared memory
     segment instead of all the attachments at that addresss.  Multiple
     shmat()'s return the same address under NOMMU-mode instead of different
     virtual addresses as under MMU-mode.

 (7) Core dumping for ELF-FDPIC requires fewer exceptions for NOMMU-mode.

 (8) /proc/maps is now the global list of mapped regions, and may list bits
     that aren't actually mapped anywhere.

 (9) /proc/meminfo gains a line (tagged "MmapCopy") that indicates the amount
     of RAM currently allocated by mmap to hold mappable regions that can't be
     mapped directly.  These are copies of the backing device or file if not
     anonymous.

These changes make NOMMU mode more similar to MMU mode.  The downside is that
NOMMU mode requires some extra memory to track things over NOMMU without this
patch (VMAs are no longer shared, and there are now region structs).

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Mike Frysinger <vapier.adi@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
2009-01-08 12:04:47 +00:00
akpm@linux-foundation.org 4c2c3b4aaf ipc/ipc_sysctl.c: move the definition of ipc_auto_callback()
proc_ipcauto_dointvec_minmax() is the only user of ipc_auto_callback(),
since the former function is protected by CONFIG_PROC_FS, so should be the
latter one.

Just move its definition down.

Signed-off-by: WANG Cong <wangcong@zeuux.org>
Cc: Eric Biederman <ebiederm@xmision.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:29 -08:00
Denis V. Lunev e953ac2195 ipc: do not goto to the next line
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: WANG Cong <wangcong@zeuux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:29 -08:00
WANG Cong e8148f7588 ipc: clean up ipc/shm.c
Use the macro shm_ids().

Remove useless check for a userspace pointer, because copy_to_user()
will check it.

Some style cleanups.

Signed-off-by: WANG Cong <wangcong@zeuux.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:29 -08:00
Linus Torvalds 520c853466 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  inotify: fix type errors in interfaces
  fix breakage in reiserfs_new_inode()
  fix the treatment of jfs special inodes
  vfs: remove duplicate code in get_fs_type()
  add a vfs_fsync helper
  sys_execve and sys_uselib do not call into fsnotify
  zero i_uid/i_gid on inode allocation
  inode->i_op is never NULL
  ntfs: don't NULL i_op
  isofs check for NULL ->i_op in root directory is dead code
  affs: do not zero ->i_op
  kill suid bit only for regular files
  vfs: lseek(fd, 0, SEEK_CUR) race condition
2009-01-05 18:32:06 -08:00
Alan Cox 046c68842b mm: update my address
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-05 17:44:42 -08:00
Al Viro 56ff5efad9 zero i_uid/i_gid on inode allocation
... and don't bother in callers.  Don't bother with zeroing i_blocks,
while we are at it - it's already been zeroed.

i_mode is not worth the effort; it has no common default value.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-05 11:54:28 -05:00
Al Viro 564f6993ff sanitize audit_mq_open()
* don't bother with allocations
* don't do double copy_from_user()
* don't duplicate parts of check for audit_dummy_context()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:41 -05:00
Al Viro c32c8af43b sanitize AUDIT_MQ_SENDRECV
* logging the original value of *msg_prio in mq_timedreceive(2)
  is insane - the argument is write-only (i.e. syscall always
  ignores the original value and only overwrites it).
* merge __audit_mq_timed{send,receive}
* don't do copy_from_user() twice
* don't mess with allocations in auditsc part
* ... and don't bother checking !audit_enabled and !context in there -
  we'd already checked for audit_dummy_context().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:40 -05:00
Al Viro 20114f71b2 sanitize audit_mq_notify()
* don't copy_from_user() twice
* don't bother with allocations
* don't duplicate parts of audit_dummy_context()
* make it return void

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:40 -05:00
Al Viro 7392906ea9 sanitize audit_mq_getsetattr()
* get rid of allocations
* make it return void
* don't duplicate parts of audit_dummy_context()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:40 -05:00
Al Viro e816f370cb sanitize audit_ipc_set_perm()
* get rid of allocations
* make it return void
* simplify callers

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:40 -05:00
Al Viro a33e675100 sanitize audit_ipc_obj()
* get rid of allocations
* make it return void
* simplify callers

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:39 -05:00
James Morris ec98ce480a Merge branch 'master' into next
Conflicts:
	fs/nfsd/nfs4recover.c

Manually fixed above to use new creds API functions, e.g.
nfs4_save_creds().

Signed-off-by: James Morris <jmorris@namei.org>
2008-12-04 17:16:36 +11:00
Nadia Derbey e00b4ff7eb sysvipc: fix the ipc structures initialization
A problem was found while reviewing the code after Bugzilla bug
http://bugzilla.kernel.org/show_bug.cgi?id=11796.

In ipc_addid(), the newly allocated ipc structure is inserted into the
ipcs tree (i.e made visible to readers) without locking it.  This is not
correct since its initialization continues after it has been inserted in
the tree.

This patch moves the ipc structure lock initialization + locking before
the actual insertion.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Reported-by: Clement Calmels <cboulte@gmail.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: <stable@kernel.org>		[2.6.27.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-19 18:49:57 -08:00
David Howells 745ca2475a CRED: Pass credentials through dentry_open()
Pass credentials through dentry_open() so that the COW creds patch can have
SELinux's flush_unauthorized_files() pass the appropriate creds back to itself
when it opens its null chardev.

The security_dentry_open() call also now takes a creds pointer, as does the
dentry_open hook in struct security_operations.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: James Morris <jmorris@namei.org>
2008-11-14 10:39:22 +11:00
David Howells 86a264abe5 CRED: Wrap current->cred and a few other accessors
Wrap current->cred and a few other accessors to hide their actual
implementation.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-11-14 10:39:18 +11:00
David Howells b6dff3ec5e CRED: Separate task security context from task_struct
Separate the task security context from task_struct.  At this point, the
security data is temporarily embedded in the task_struct with two pointers
pointing to it.

Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in
entry.S via asm-offsets.

With comment fixes Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-11-14 10:39:16 +11:00
David Howells 414c0708d0 CRED: Wrap task credential accesses in the SYSV IPC subsystem
Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.

Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().

Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-11-14 10:39:06 +11:00
Al Viro aeb5d72706 [PATCH] introduce fmode_t, do annotations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-21 07:47:06 -04:00
Joe Korty b231cca438 message queues: increase range limits
Increase the range of various posix message queue limits.

Posix gives the message queue user the ability to 'trade off' the maximum
size of messages with the number of possible messages that can be 'in
flight'.  Linux currently makes this trade off more restrictive than it
needs to be.

In particular, the maximum message size today can be made no smaller than
8192.  This greatly restricts those applications that would like to have
the ability to post large numbers of very small messages.

So this task lowers the limit that the maximum message size can be set to,
from 8192 to 128.  It also lowers the limit that the maximum #number of
messages in flight can be set to, from 10 to 1.

With these changes the message queue user can make better trade offs
between #messages and message size, in order to get everything to fit
within the setrlimit(RLIMIT_MSGQUEUE) limit for that particular user.

This patch also applies the values in

	/proc/sys/fs/mqueue/msg_max
	/proc/sys/fs/mqueue/msgsize_max

as the defaults for the max #messages allowed and the max message size
allowed, respectively, for those applications that do not supply these.
Previously, the defaults were hardwired to 10 and 8192, respectively.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Joe Korty <joe.korty@ccur.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:40 -07:00
Lee Schermerhorn 89e004ea55 SHM_LOCKED pages are unevictable
Shmem segments locked into memory via shmctl(SHM_LOCKED) should not be
kept on the normal LRU, since scanning them is a waste of time and might
throw off kswapd's balancing algorithms.  Place them on the unevictable
LRU list instead.

Use the AS_UNEVICTABLE flag to mark address_space of SHM_LOCKed shared
memory regions as unevictable.  Then these pages will be culled off the
normal LRU lists during vmscan.

Add new wrapper function to clear the mapping's unevictable state when/if
shared memory segment is munlocked.

Add 'scan_mapping_unevictable_page()' to mm/vmscan.c to scan all pages in
the shmem segment's mapping [struct address_space] for evictability now
that they're no longer locked.  If so, move them to the appropriate zone
lru list.

Changes depend on [CONFIG_]UNEVICTABLE_LRU.

[kosaki.motohiro@jp.fujitsu.com: revert shm change]
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Kosaki Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:50:26 -07:00
Adrian Bunk 6d97e2345a ipc/sem.c: make free_un() static
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:51 -07:00
Alexey Dobriyan f221e726bf sysctl: simplify ->strategy
name and nlen parameters passed to ->strategy hook are unused, remove
them.  In general ->strategy hook should know what it's doing, and don't
do something tricky for which, say, pointer to original userspace array
may be needed (name).

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net> [ networking bits ]
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Matt Mackall <mpm@selenic.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:47 -07:00
Al Viro f419a2e3b6 [PATCH] kill nameidata passing to permission(), rename to inode_permission()
Incidentally, the name that gives hundreds of false positives on grep
is not a good idea...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:31 -04:00
Alexey Dobriyan 51cc50685a SL*B: drop kmem cache argument from constructor
Kmem cache passed to constructor is only needed for constructors that are
themselves multiplexeres.  Nobody uses this "feature", nor does anybody uses
passed kmem cache in non-trivial way, so pass only pointer to object.

Non-trivial places are:
	arch/powerpc/mm/init_64.c
	arch/powerpc/mm/hugetlbpage.c

This is flag day, yes.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Jon Tollefson <kniht@linux.vnet.ibm.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Matt Mackall <mpm@selenic.com>
[akpm@linux-foundation.org: fix arch/powerpc/mm/hugetlbpage.c]
[akpm@linux-foundation.org: fix mm/slab.c]
[akpm@linux-foundation.org: fix ubifs]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 12:00:07 -07:00
Nadia Derbey 9eefe520c8 ipc: do not use a negative value to re-enable msgmni automatic recomputing
This patch proposes an alternative to the "magical
positive-versus-negative number trick" Andrew complained about last week
in http://lkml.org/lkml/2008/6/24/418.

This had been introduced with the patches that scale msgmni to the amount
of lowmem.  With these patches, msgmni has a registered notification
routine that recomputes msgmni value upon memory add/remove or ipc
namespace creation/ removal.

When msgmni is changed from user space (i.e.  value written to the proc
file), that notification routine is unregistered, and the way to make it
registered back is to write a negative value into the proc file.  This is
the "magical positive-versus-negative number trick".

To fix this, a new proc file is introduced: /proc/sys/kernel/auto_msgmni.
This file acts as ON/OFF for msgmni automatic recomputing.

With this patch, the process is the following:
1) kernel boots in "automatic recomputing mode"
   /proc/sys/kernel/msgmni contains the value that has been computed (depends
                           on lowmem)
   /proc/sys/kernel/automatic_msgmni contains "1"

2) echo <val> > /proc/sys/kernel/msgmni
   . sets msg_ctlmni to <val>
   . de-activates automatic recomputing (i.e. if, say, some memory is added
     msgmni won't be recomputed anymore)
   . /proc/sys/kernel/automatic_msgmni now contains "0"

3) echo "0" > /proc/sys/kernel/automatic_msgmni
   . de-activates msgmni automatic recomputing
     this has the same effect as 2) except that msg_ctlmni's value stays
     blocked at its current value)

3) echo "1" > /proc/sys/kernel/automatic_msgmni
   . recomputes msgmni's value based on the current available memory size
     and number of ipc namespaces
   . re-activates automatic recomputing for msgmni.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Solofo Ramangalahy <Solofo.Ramangalahy@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:42 -07:00
Akinobu Mita f1a43f93f0 ipc: use simple_read_from_buffer()
Also this patch kills unneccesary trailing NULL character.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:42 -07:00
Manfred Spraul 380af1b33b ipc/sem.c: rewrite undo list locking
The attached patch:
- reverses the locking order of ulp->lock and sem_lock:
  Previously, it was first ulp->lock, then inside sem_lock.
  Now it's the other way around.
- converts the undo structure to rcu.

Benefits:
- With the old locking order, IPC_RMID could not kfree the undo structures.
  The stale entries remained in the linked lists and were released later.
- The patch fixes a a race in semtimedop(): if both IPC_RMID and a semget() that
  recreates exactly the same id happen between find_alloc_undo() and sem_lock,
  then semtimedop() would access already kfree'd memory.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Reviewed-by: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:42 -07:00
Manfred Spraul a1193f8ec0 ipc/sem.c: convert sem_array.sem_pending to struct list_head
sem_array.sem_pending is a double linked list, the attached patch converts
it to struct list_head.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Reviewed-by: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:42 -07:00
Manfred Spraul 2c0c29d414 ipc/sem.c: remove unused entries from struct sem_queue
sem_queue.sma and sem_queue.id were never used, the attached patch removes
them.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Reviewed-by: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:42 -07:00
Manfred Spraul 4daa28f6d8 ipc/sem.c: convert undo structures to struct list_head
The undo structures contain two linked lists, the attached patch replaces
them with generic struct list_head lists.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:42 -07:00
Nadia Derbey 00c2bf85d8 ipc: get rid of ipc_lock_down()
Remove the ipc_lock_down() routines: they used to call idr_find() locklessly
(given that the ipc ids lock was already held), so they are not needed
anymore.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Acked-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Jim Houston <jim.houston@comcast.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:42 -07:00
Nadia Derbey 983bfb7db3 ipc: call idr_find() without locking in ipc_lock()
Call idr_find() locklessly from ipc_lock(), since the idr tree is now RCU
protected.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Acked-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Jim Houston <jim.houston@comcast.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:42 -07:00
Andi Kleen a551643895 hugetlb: modular state for hugetlb page size
The goal of this patchset is to support multiple hugetlb page sizes.  This
is achieved by introducing a new struct hstate structure, which
encapsulates the important hugetlb state and constants (eg.  huge page
size, number of huge pages currently allocated, etc).

The hstate structure is then passed around the code which requires these
fields, they will do the right thing regardless of the exact hstate they
are operating on.

This patch adds the hstate structure, with a single global instance of it
(default_hstate), and does the basic work of converting hugetlb to use the
hstate.

Future patches will add more hstate structures to allow for different
hugetlbfs mounts to have different page sizes.

[akpm@linux-foundation.org: coding-style fixes]
Acked-by: Adam Litke <agl@us.ibm.com>
Acked-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:17 -07:00
David S. Miller 4ae127d1b6 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:

	drivers/net/smc911x.c
2008-06-13 20:52:39 -07:00
Paul Menage 6c826818ff /proc/sysvipc/shm: fix 32-bit truncation of segment sizes
sysvipc_shm_proc_show() picks between format strings (based on the
expected maximum length of a SHM segment) in a way that prevents gcc from
performing format checks on the seq_printf() parameters.  This hid two
format errors - shp->shm_segsz and shp->shm_nattach are both unsigned
long, but were being printed as unsigned int and signed int respectively.
This leads to 32-bit truncation of SHM segment sizes reported in
/proc/sysvipc/shm.  (And for nattach, but that's less of a problem for
most users).

This patch makes the format string directly visible to gcc's format
specifier checker, and fixes the two broken format specifiers.

Signed-off-by: Paul Menage <menage@google.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-06-12 18:05:41 -07:00
Neil Horman c592713b3e shm: Remove silly double assignment
Found a silly double assignment of err is do_shmat.  Silly, but good to
clean up the useless code.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-06-10 07:58:00 -07:00
Nadia Derbey dfcceb26f8 ipc: only output msgmni value at boot time
When posting:
[PATCH 1/8] Scaling msgmni to the amount of lowmem
(see http://lkml.org/lkml/2008/2/11/171), I have added a KERN_INFO message
that is output each time msgmni is recomputed.

In http://lkml.org/lkml/2008/4/29/575 Tony Luck complained that this
message references an ipc namespace address that is useless.

I first thought of using an audit_log instead of a printk, as suggested by
Serge Hallyn.  But unfortunately, we do not have any other information
than the namespace address to provide here too.  So I chose to move the
message and output it only at boot time, removing the reference to the
namespace.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Cc: "Serge E. Hallyn" <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-06-06 11:29:12 -07:00
Denis V. Lunev 9457afee85 netlink: Remove nonblock parameter from netlink_attachskb
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-05 11:23:39 -07:00
Ulrich Drepper 269f21344b tiny mq_open optimization
A very small cleanup for mq_open.

We do not have to call set_close_on_exit if we create the file
descriptor right away with the flag set.  We have a function for this
now.  The resulting code is smaller and a tiny bit faster.

Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-03 13:50:33 -07:00
Denis V. Lunev 6a6375db13 sysvipc: use non-racy method for proc entries creation
Use proc_create_data() to make sure that ->proc_fops and ->data be setup
before gluing PDE to main tree.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:20 -07:00
Manfred Spraul 9edff4ab1f ipc: sysvsem: implement sys_unshare(CLONE_SYSVSEM)
sys_unshare(CLONE_NEWIPC) doesn't handle the undo lists properly, this can
cause a kernel memory corruption.  CLONE_NEWIPC must detach from the existing
undo lists.

Fix, part 1: add support for sys_unshare(CLONE_SYSVSEM)

The original reason to not support it was the potential (inevitable?)
confusion due to the fact that sys_unshare(CLONE_SYSVSEM) has the
inverse meaning of clone(CLONE_SYSVSEM).

Our two most reasonable options then appear to be (1) fully support
CLONE_SYSVSEM, or (2) continue to refuse explicit CLONE_SYSVSEM,
but always do it anyway on unshare(CLONE_SYSVSEM).  This patch does
(1).

Changelog:
	Apr 16: SEH: switch to Manfred's alternative patch which
		removes the unshare_semundo() function which
		always refused CLONE_SYSVSEM.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:14 -07:00
Zhang, Yanmin 44f564a4bf ipc: add definitions of USHORT_MAX and others
Add definitions of USHORT_MAX and others into kernel.  ipc uses it and slub
implementation might also use it.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
Reviewed-by: Christoph Lameter <clameter@sgi.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: "Pierre Peiffer" <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:14 -07:00
Pierre Peiffer a5f75e7f25 IPC: consolidate all xxxctl_down() functions
semctl_down(), msgctl_down() and shmctl_down() are used to handle the same set
of commands for each kind of IPC.  They all start to do the same job (they
retrieve the ipc and do some permission checks) before handling the commands
on their own.

This patch proposes to consolidate this by moving these same pieces of code
into one common function called ipcctl_pre_down().

It simplifies a little these xxxctl_down() functions and increases a little
the maintainability.

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:14 -07:00
Pierre Peiffer 8f4a3809c1 IPC: introduce ipc_update_perm()
The IPC_SET command performs the same permission setting for all IPCs.  This
patch introduces a common ipc_update_perm() function to update these
permissions and makes use of it for all IPCs.

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:13 -07:00
Pierre Peiffer 016d7132f2 IPC: get rid of the use *_setbuf structure.
All IPCs make use of an intermetiate *_setbuf structure to handle the IPC_SET
command.  This is not really needed and, moreover, it complicates a little bit
the code.

This patch gets rid of the use of it and uses directly the semid64_ds/
msgid64_ds/shmid64_ds structure.

In addition of removing one struture declaration, it also simplifies and
improves a little bit the common 64-bits path.

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:13 -07:00
Pierre Peiffer 21a4826a7c IPC/semaphores: remove one unused parameter from semctl_down()
semctl_down() takes one unused parameter: semnum.  This patch proposes to get
rid of it.

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:13 -07:00
Pierre Peiffer 522bb2a2b4 IPC/semaphores: move the rwmutex handling inside semctl_down
semctl_down is called with the rwmutex (the one which protects the list of
ipcs) taken in write mode.

This patch moves this rwmutex taken in write-mode inside semctl_down.

This has the advantages of reducing a little bit the window during which this
rwmutex is taken, clarifying sys_semctl, and finally of having a coherent
behaviour with [shm|msg]ctl_down

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:13 -07:00
Pierre Peiffer a0d092fc2d IPC/message queues: introduce msgctl_down
Currently, sys_msgctl is not easy to read.

This patch tries to improve that by introducing the msgctl_down function to
handle all commands requiring the rwmutex to be taken in write mode (ie
IPC_SET and IPC_RMID for now).  It is the equivalent function of semctl_down
for message queues.

This greatly changes the readability of sys_msgctl and also harmonizes the way
these commands are handled among all IPCs.

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:13 -07:00
Pierre Peiffer 8d4cc8b5c5 IPC/shared memory: introduce shmctl_down
Currently, the way the different commands are handled in sys_shmctl introduces
some duplicated code.

This patch introduces the shmctl_down function to handle all the commands
requiring the rwmutex to be taken in write mode (ie IPC_SET and IPC_RMID for
now).  It is the equivalent function of semctl_down for shared memory.

This removes some duplicated code for handling these both commands and
harmonizes the way they are handled among all IPCs.

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:13 -07:00
Pierre Peiffer 6ff3797218 IPC/semaphores: code factorisation
Trivial patch which adds some small locking functions and makes use of them to
factorize some part of the code and to make it cleaner.

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:13 -07:00
Nadia Derbey 6546bc4279 ipc: re-enable msgmni automatic recomputing msgmni if set to negative
The enhancement as asked for by Yasunori: if msgmni is set to a negative
value, register it back into the ipcns notifier chain.

A new interface has been added to the notification mechanism:
notifier_chain_cond_register() registers a notifier block only if not already
registered.  With that new interface we avoid taking care of the states
changes in procfs.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: Pierre Peiffer <pierre.peiffer@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:13 -07:00
Nadia Derbey 91cfb2b4b5 ipc: do not recompute msgmni anymore if explicitly set by user
Make msgmni not recomputed anymore upon ipc namespace creation / removal or
memory add/remove, as soon as it has been set from userland.

As soon as msgmni is explicitly set via procfs or sysctl(), the associated
callback routine is unregistered from the ipc namespace notifier chain.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: Pierre Peiffer <pierre.peiffer@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:13 -07:00
Nadia Derbey e2c284d8a8 ipc: recompute msgmni on ipc namespace creation/removal
Introduce a notification mechanism that aims at recomputing msgmni each time
an ipc namespace is created or removed.

The ipc namespace notifier chain already defined for memory hotplug management
is used for that purpose too.

Each time a new ipc namespace is allocated or an existing ipc namespace is
removed, the ipcns notifier chain is notified.  The callback routine for each
registered ipc namespace is then activated in order to recompute msgmni for
that namespace.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: Pierre Peiffer <pierre.peiffer@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:12 -07:00
Nadia Derbey 424450c1db ipc: invoke the ipcns notifier chain as a work item
Make the memory hotplug chain's mutex held for a shorter time: when memory is
offlined or onlined a work item is added to the global workqueue.  When the
work item is run, it notifies the ipcns notifier chain with the
IPCNS_MEMCHANGED event.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: Pierre Peiffer <pierre.peiffer@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:12 -07:00
Nadia Derbey b6b337ad1c ipc: recompute msgmni on memory add / remove
Introduce the registration of a callback routine that recomputes msg_ctlmni
upon memory add / remove.

A single notifier block is registered in the hotplug memory chain for all the
ipc namespaces.

Since the ipc namespaces are not linked together, they have their own
notification chain: one notifier_block is defined per ipc namespace.

Each time an ipc namespace is created (removed) it registers (unregisters) its
notifier block in (from) the ipcns chain.  The callback routine registered in
the memory chain invokes the ipcns notifier chain with the IPCNS_LOWMEM event.
 Each callback routine registered in the ipcns namespace, in turn, recomputes
msgmni for the owning namespace.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: Pierre Peiffer <pierre.peiffer@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:12 -07:00
Nadia Derbey 4d89dc6ab2 ipc: scale msgmni to the number of ipc namespaces
Since all the namespaces see the same amount of memory (the total one) this
patch introduces a new variable that counts the ipc namespaces and divides
msg_ctlmni by this counter.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: Pierre Peiffer <pierre.peiffer@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:12 -07:00
Nadia Derbey f7bf3df8be ipc: scale msgmni to the amount of lowmem
On large systems we'd like to allow a larger number of message queues.  In
some cases up to 32K.  However simply setting MSGMNI to a larger value may
cause problems for smaller systems.

The first patch of this series introduces a default maximum number of message
queue ids that scales with the amount of lowmem.

Since msgmni is per namespace and there is no amount of memory dedicated to
each namespace so far, the second patch of this series scales msgmni to the
number of ipc namespaces too.

Since msgmni depends on the amount of memory, it becomes necessary to
recompute it upon memory add/remove.  In the 4th patch, memory hotplug
management is added: a notifier block is registered into the memory hotplug
notifier chain for the ipc subsystem.  Since the ipc namespaces are not linked
together, they have their own notification chain: one notifier_block is
defined per ipc namespace.  Each time an ipc namespace is created (removed) it
registers (unregisters) its notifier block in (from) the ipcns chain.  The
callback routine registered in the memory chain invokes the ipcns notifier
chain with the IPCNS_MEMCHANGE event.  Each callback routine registered in the
ipcns namespace, in turn, recomputes msgmni for the owning namespace.

The 5th patch makes it possible to keep the memory hotplug notifier chain's
lock for a lesser amount of time: instead of directly notifying the ipcns
notifier chain upon memory add/remove, a work item is added to the global
workqueue.  When activated, this work item is the one who notifies the ipcns
notifier chain.

Since msgmni depends on the number of ipc namespaces, it becomes necessary to
recompute it upon ipc namespace creation / removal.  The 6th patch uses the
ipc namespace notifier chain for that purpose: that chain is notified each
time an ipc namespace is created or removed.  This makes it possible to
recompute msgmni for all the namespaces each time one of them is created or
removed.

When msgmni is explicitely set from userspace, we should avoid recomputing it
upon memory add/remove or ipcns creation/removal.  This is what the 7th patch
does: it simply unregisters the ipcns callback routine as soon as msgmni has
been changed from procfs or sysctl().

Even if msgmni is set by hand, it should be possible to make it back
automatically recomputed upon memory add/remove or ipcns creation/removal.
This what is achieved in patch 8: if set to a negative value, msgmni is added
back to the ipcns notifier chain, making it automatically recomputed again.

This patch:

Compute msg_ctlmni to make it scale with the amount of lowmem.  msg_ctlmni is
now set to make the message queues occupy 1/32 of the available lowmem.

Some cleaning has also been done for the MSGPOOL constant: the msgctl man page
says it's not used, but it also defines it as a size in bytes (the code
expresses it in Kbytes).

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: Pierre Peiffer <pierre.peiffer@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:12 -07:00
Pierre Peiffer 48dea404ed IPC: use ipc_buildid() directly from ipc_addid()
By continuing to consolidate a little the IPC code, each id can be built
directly in ipc_addid() instead of having it built from each callers of
ipc_addid()

And I also remove shm_addid() in order to have, as much as possible, the
same code for shm/sem/msg.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:12 -07:00
Lee Schermerhorn 52cd3b0740 mempolicy: rework mempolicy Reference Counting [yet again]
After further discussion with Christoph Lameter, it has become clear that my
earlier attempts to clean up the mempolicy reference counting were a bit of
overkill in some areas, resulting in superflous ref/unref in what are usually
fast paths.  In other areas, further inspection reveals that I botched the
unref for interleave policies.

A separate patch, suitable for upstream/stable trees, fixes up the known
errors in the previous attempt to fix reference counting.

This patch reworks the memory policy referencing counting and, one hopes,
simplifies the code.  Maybe I'll get it right this time.

See the update to the numa_memory_policy.txt document for a discussion of
memory policy reference counting that motivates this patch.

Summary:

Lookup of mempolicy, based on (vma, address) need only add a reference for
shared policy, and we need only unref the policy when finished for shared
policies.  So, this patch backs out all of the unneeded extra reference
counting added by my previous attempt.  It then unrefs only shared policies
when we're finished with them, using the mpol_cond_put() [conditional put]
helper function introduced by this patch.

Note that shmem_swapin() calls read_swap_cache_async() with a dummy vma
containing just the policy.  read_swap_cache_async() can call alloc_page_vma()
multiple times, so we can't let alloc_page_vma() unref the shared policy in
this case.  To avoid this, we make a copy of any non-null shared policy and
remove the MPOL_F_SHARED flag from the copy.  This copy occurs before reading
a page [or multiple pages] from swap, so the overhead should not be an issue
here.

I introduced a new static inline function "mpol_cond_copy()" to copy the
shared policy to an on-stack policy and remove the flags that would require a
conditional free.  The current implementation of mpol_cond_copy() assumes that
the struct mempolicy contains no pointers to dynamically allocated structures
that must be duplicated or reference counted during copy.

Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:24 -07:00
Lee Schermerhorn ae4d8c16aa mempolicy: fixup Fallback for Default Shmem Policy
get_vma_policy() is not handling fallback to task policy correctly when the
get_policy() vm_op returns NULL.  The NULL overwrites the 'pol' variable that
was holding the fallback task mempolicy.  So, it was falling back directly to
system default policy.

Fix get_vma_policy() to use only non-NULL policy returned from the vma
get_policy op.

shm_get_policy() was falling back to current task's mempolicy if the "backing
file system" [tmpfs vs hugetlbfs] does not support the get_policy vm_op and
the vma policy is null.  This is incorrect for show_numa_maps() which is
likely querying the numa_maps of some task other than current.  Remove this
fallback.

Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:24 -07:00
Dave Hansen 4a3fd211cc [PATCH] r/o bind mounts: elevate write count for open()s
This is the first really tricky patch in the series.  It elevates the writer
count on a mount each time a non-special file is opened for write.

We used to do this in may_open(), but Miklos pointed out that __dentry_open()
is used as well to create filps.  This will cover even those cases, while a
call in may_open() would not have.

There is also an elevated count around the vfs_create() call in open_namei().
See the comments for more details, but we need this to fix a 'create, remount,
fail r/w open()' race.

Some filesystems forego the use of normal vfs calls to create
struct files.   Make sure that these users elevate the mnt
writer count because they will get __fput(), and we need
to make sure they're balanced.

Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-19 00:29:25 -04:00
Dave Hansen 0622753b80 [PATCH] r/o bind mounts: elevate write count for rmdir and unlink.
Elevate the write count during the vfs_rmdir() and vfs_unlink().

[AV: merged rmdir and unlink parts, added missing pieces in nfsd]

Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-19 00:25:33 -04:00
Lee Schermerhorn 69682d852f mempolicy: fix reference counting bugs
Address 3 known bugs in the current memory policy reference counting method.
I have a series of patches to rework the reference counting to reduce overhead
in the allocation path.  However, that series will require testing in -mm once
I repost it.

1) alloc_page_vma() does not release the extra reference taken for
   vma/shared mempolicy when the mode == MPOL_INTERLEAVE.  This can result in
   leaking mempolicy structures.  This is probably occurring, but not being
   noticed.

   Fix:  add the conditional release of the reference.

2) hugezonelist unconditionally releases a reference on the mempolicy when
   mode == MPOL_INTERLEAVE.  This can result in decrementing the reference
   count for system default policy [should have no ill effect] or premature
   freeing of task policy.  If this occurred, the next allocation using task
   mempolicy would use the freed structure and probably BUG out.

   Fix:  add the necessary check to the release.

3) The current reference counting method assumes that vma 'get_policy()'
   methods automatically add an extra reference a non-NULL returned mempolicy.
    This is true for shmem_get_policy() used by tmpfs mappings, including
   regular page shm segments.  However, SHM_HUGETLB shm's, backed by
   hugetlbfs, just use the vma policy without the extra reference.  This
   results in freeing of the vma policy on the first allocation, with reuse of
   the freed mempolicy structure on subsequent allocations.

   Fix: Rather than add another condition to the conditional reference
   release, which occur in the allocation path, just add a reference when
   returning the vma policy in shm_get_policy() to match the assumptions.

Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Greg KH <greg@kroah.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: David Rientjes <rientjes@google.com>
Cc: <eric.whitney@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-10 18:01:19 -07:00
Pavel Emelyanov 56496c1d83 Pidns: fix badly converted mqueues pid handling
When sending the pid namespaces patches I wrongly converted the tsk->tgid into
task_pid_vnr(tsk) in mqueue-s (the git id of this patch is
b488893a39).

The proper behavior is to get the task_tgid_vnr(tsk).

This seem to be the only mistake of that kind.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:29 -08:00
Pavel Emelyanov 6c5f3e7b43 Pidns: make full use of xxx_vnr() calls
Some time ago the xxx_vnr() calls (e.g.  pid_vnr or find_task_by_vpid) were
_all_ converted to operate on the current pid namespace.  After this each call
like xxx_nr_ns(foo, current->nsproxy->pid_ns) is nothing but a xxx_vnr(foo)
one.

Switch all the xxx_nr_ns() callers to use the xxx_vnr() calls where
appropriate.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Reviewed-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:29 -08:00
Pierre Peiffer 01b8b07a5d IPC: consolidate sem_exit_ns(), msg_exit_ns() and shm_exit_ns()
sem_exit_ns(), msg_exit_ns() and shm_exit_ns() are all called when an
ipc_namespace is released to free all ipcs of each type.  But in fact, they
do the same thing: they loop around all ipcs to free them individually by
calling a specific routine.

This patch proposes to consolidate this by introducing a common function,
free_ipcs(), that do the job.  The specific routine to call on each
individual ipcs is passed as parameter.  For this, these ipc-specific
'free' routines are reworked to take a generic 'struct ipc_perm' as
parameter.

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:26 -08:00
Pierre Peiffer ed2ddbf88c IPC: make struct ipc_ids static in ipc_namespace
Each ipc_namespace contains a table of 3 pointers to struct ipc_ids (3 for
msg, sem and shm, structure used to store all ipcs) These 'struct ipc_ids'
are dynamically allocated for each icp_namespace as the ipc_namespace
itself (for the init namespace, they are initialized with pointers to
static variables instead)

It is so for historical reason: in fact, before the use of idr to store the
ipcs, the ipcs were stored in tables of variable length, depending of the
maximum number of ipc allowed.  Now, these 'struct ipc_ids' have a fixed
size.  As they are allocated in any cases for each new ipc_namespace, there
is no gain of memory in having them allocated separately of the struct
ipc_namespace.

This patch proposes to make this table static in the struct ipc_namespace.
Thus, we can allocate all in once and get rid of all the code needed to
allocate and free these ipc_ids separately.

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Acked-by: Cedric Le Goater <clg@fr.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:26 -08:00
Pierre Peiffer 4b9fcb0ec6 IPC/semaphores: consolidate SEM_STAT and IPC_STAT commands
These commands (SEM_STAT and IPC_STAT) are rather doing the same things
(only the meaning of the id given as input and the return value differ).
However, for the semaphores, they are handled in two different places (two
different functions).

This patch consolidates this for clarification by handling these both
commands in the same place in semctl_nolock().  It also removes one unused
parameter for this function.

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:26 -08:00
Pavel Emelyanov b2d75cddc8 ipc: uninline some code from util.h
ipc_lock_check_down(), ipc_lock_check() and ipcget() seem too large to be
inline.  Besides, they give no optimization being inline as they perform
calls inside in any case.

Moving them into ipc/util.c saves 500 bytes of vmlinux and shortens IPC
internal API.

$ ./scripts/bloat-o-meter vmlinux-orig vmlinux
add/remove: 3/2 grow/shrink: 0/10 up/down: 490/-989 (-499)
function                                     old     new   delta
ipcget                                         -     392    +392
ipc_lock_check_down                            -      49     +49
ipc_lock_check                                 -      49     +49
sys_semget                                   119     105     -14
sys_shmget                                   108      86     -22
sys_msgget                                   100      78     -22
do_msgsnd                                    665     631     -34
do_msgrcv                                    680     644     -36
do_shmat                                     771     733     -38
sys_msgctl                                  1302    1229     -73
ipcget_new                                    80       -     -80
sys_semtimedop                              1534    1452     -82
sys_semctl                                  2034    1922    -112
sys_shmctl                                  1919    1765    -154
ipcget_public                                322       -    -322

The ipcget() growth is the result of gcc inlining of currently static
ipcget_new/_public.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:25 -08:00
Pavel Emelyanov ae5e1b22f1 namespaces: move the IPC namespace under IPC_NS option
Currently the IPC namespace management code is spread over the ipc/*.c files.
I moved this code into ipc/namespace.c file which is compiled out when needed.

The linux/ipc_namespace.h file is used to store the prototypes of the
functions in namespace.c and the stubs for NAMESPACES=n case.  This is done
so, because the stub for copy_ipc_namespace requires the knowledge of the
CLONE_NEWIPC flag, which is in sched.h.  But the linux/ipc.h file itself in
included into many many .c files via the sys.h->sem.h sequence so adding the
sched.h into it will make all these .c depend on sched.h which is not that
good.  On the other hand the knowledge about the namespaces stuff is required
in 4 .c files only.

Besides, this patch compiles out some auxiliary functions from ipc/sem.c,
msg.c and shm.c files.  It turned out that moving these functions into
namespaces.c is not that easy because they use many other calls and macros
from the original file.  Moving them would make this patch complicated.  On
the other hand all these functions can be consolidated, so I will send a
separate patch doing this a bit later.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:23 -08:00
Adrian Bunk b524b9adb3 make ipc/util.c:sysvipc_find_ipc() static
sysvipc_find_ipc() can become static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 10:41:01 -08:00
Pierre Peiffer b1ed88b47f IPC: fix error check in all new xxx_lock() and xxx_exit_ns() functions
In the new implementation of the [sem|shm|msg]_lock[_check]() routines, we
use the return value of ipc_lock() in container_of() without any check.
But ipc_lock may return a errcode.  The use of this errcode in
container_of() may alter this errcode, and we don't want this.

And in xxx_exit_ns, the pointer return by idr_find is of type 'struct
kern_ipc_per'...

Today, the code will work as is because the member used in these
container_of() is the first member of its container (offset == 0), the
errcode isn't changed then.  But in the general case, we can't count on
this assumption and this may lead later to a real bug if we don't correct
this.

Again, the proposed solution is simple and correct.  But, as pointed by
Nadia, with this solution, the same check will be done several times (in
all sub-callers...), what is not very funny/optimal...

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 10:41:01 -08:00
Pavel Emelyanov fd79b77117 ipc: lost unlock and fput in mqueue.c on error path
The error path in sys_mq_getsetattr() after the call to
audit_mq_getsetattr() is wrong - the info->lock is not unlocked and the
struct file *filp is not put.

Fix them both.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Pierre Peiffer <pierre.peiffer@bull.net>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-29 09:24:52 -08:00
Patrick McHardy c3d8d1e30c [NETLINK]: Fix unicast timeouts
Commit ed6dcf4a in the history.git tree broke netlink_unicast timeouts
by moving the schedule_timeout() call to a new function that doesn't
propagate the remaining timeout back to the caller. This means on each
retry we start with the full timeout again.

ipc/mqueue.c seems to actually want to wait indefinitely so this
behaviour is retained.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-07 04:15:12 -08:00
Al Viro 5a190ae697 [PATCH] pass dentry to audit_inode()/audit_inode_child()
makes caller simpler *and* allows to scan ancestors

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2007-10-21 02:37:18 -04:00
Pierre Peiffer 283bb7fada IPC: fix error case when idr-cache is empty in ipcget()
With the use of idr to store the ipc, the case where the idr cache is
empty, when idr_get_new is called (this may happen even if we call
idr_pre_get() before), is not well handled: it lets
semget()/shmget()/msgget() return ENOSPC when this cache is empty, what 1.
does not reflect the facts and 2.  does not conform to the man(s).

This patch fixes this by retrying the whole process of allocation in this case.

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:49 -07:00
Kirill Korotaev 3ac88a41ff virtualization of sysv msg queues is incomplete
Virtualization of sysv msg queues is incomplete: msg_hdrs and msg_bytes
variables visible from userspace are global.  Let's make them
per-namespace.

Signed-off-by: Alexey Kuznetsov <alexey@openvz.org>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
Cc: Pierre Peiffer <pierre.peiffer@bull.net>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Serge Hallyn <serue@us.ibm.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:48 -07:00
Pierre Peiffer c530c6ac7e IPC: cleanup some code and wrong comments about semundo list managment
Some comments about sem_undo_list seem wrong.
About the comment above unlock_semundo:
"... If task2 now exits before task1 releases the lock (by calling
unlock_semundo()), then task1 will never call spin_unlock(). ..."

This is just wrong, I see no reason for which task1 will not call
spin_unlock... The rest of this comment is also wrong... Unless I
miss something (of course).

Finally, (un)lock_semundo functions are useless, so remove them
for simplification. (this avoids an useless if statement)

Signed-off-by: Pierre Peiffer <pierre.peiffer@bull.net>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:48 -07:00
Nadia Derbey 1b531f2136 ipc: remove unneeded parameters
Remvoe the unneeded parameters from ipc_checkid() and ipc_buildid()
interfaces.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:48 -07:00
Nadia Derbey 3e148c7993 fix idr_find() locking
This is a patch that fixes the way idr_find() used to be called in ipc_lock():
in all the paths that don't imply an update of the ipcs idr, it was called
without the idr tree being locked.

The changes are:
  . in ipc_ids, the mutex has been changed into a reader/writer semaphore.
  . ipc_lock() now takes the mutex as a reader during the idr_find().
  . a new routine ipc_lock_down() has been defined: it doesn't take the
    mutex, assuming that it is being held by the caller. This is the routine
    that is now called in all the update paths.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Acked-by: Jarek Poplawski <jarkao2@o2.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:48 -07:00
Nadia Derbey f4566f0485 ipc: fix wrong comments
This patch fixes the wrong / obsolete comments in the ipc code.  Also adds
a missing lock around ipc_get_maxid() in shm_get_stat().

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:47 -07:00
Nadia Derbey 2802831313 ipc: inline ipc_buildid()
This is a trivial patch that changes the ipc_buildid() routine into a static
inline.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:47 -07:00
Nadia Derbey ce621f5ba5 ipc: introduce the ipcid_to_idx macro
This is a trivial patch that changes all the (id % SEQ_MULTIPLIER) into a call
to the ipcid_to_idx(id) macro.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:46 -07:00
Nadia Derbey 03f02c7657 Storing ipcs into IDRs
This patch converts casts of struct kern_ipc_perm to
   . struct msg_queue
   . struct sem_array
   . struct shmid_kernel
into the equivalent container_of() macro. It improves code maintenance
because the code need not change if kern_ipc_perm is no longer at the
beginning of the containing struct.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:46 -07:00
Nadia Derbey 023a53557e ipc: integrate ipc_checkid() into ipc_lock()
This patch introduces a new ipc_lock_check() routine interface:
   . each time ipc_checkid() is called, this is done after calling ipc_lock().
     ipc_checkid() is now called from inside ipc_lock_check().

[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix RCU locking]
Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:44 -07:00
Nadia Derbey 637c366340 ipc: remove the ipc_get() routine
This is a trivial patch that removes the ipc_get() routine: it is replaced
by a call to idr_find().

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:44 -07:00
Nadia Derbey 7748dbfaa0 ipc: unify the syscalls code
This patch introduces a change into the sys_msgget(), sys_semget() and
sys_shmget() routines: they now share a common code, which is better for
maintainability.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:44 -07:00
Nadia Derbey 7ca7e564e0 ipc: store ipcs into IDRs
This patch introduces ipcs storage into IDRs. The main changes are:
  . This ipc_ids structure is changed: the entries array is changed into a
    root idr structure.
  . The grow_ary() routine is removed: it is not needed anymore when adding
    an ipc structure, since we are now using the IDR facility.
  . The ipc_rmid() routine interface is changed:
       . there is no need for this routine to return the pointer passed in as
         argument: it is now declared as a void
       . since the id is now part of the kern_ipc_perm structure, no need to
         have it as an argument to the routine

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:44 -07:00
Pavel Emelyanov b488893a39 pid namespaces: changes to show virtual ids to user
This is the largest patch in the set. Make all (I hope) the places where
the pid is shown to or get from user operate on the virtual pids.

The idea is:
 - all in-kernel data structures must store either struct pid itself
   or the pid's global nr, obtained with pid_nr() call;
 - when seeking the task from kernel code with the stored id one
   should use find_task_by_pid() call that works with global pids;
 - when showing pid's numerical value to the user the virtual one
   should be used, but however when one shows task's pid outside this
   task's namespace the global one is to be used;
 - when getting the pid from userspace one need to consider this as
   the virtual one and use appropriate task/pid-searching functions.

[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: nuther build fix]
[akpm@linux-foundation.org: yet nuther build fix]
[akpm@linux-foundation.org: remove unneeded casts]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:40 -07:00
Eric W. Biederman 97aeacf492 sysctl mqueue: remove the binary sysctl numbers
Because of a conflict with FS_INODE_NR none of the binary sysctl numbers use
by mqueue, were available to user space.  So just remove them.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 14:37:22 -07:00
Dave Hansen ce8d2cdf3d r/o bind mounts: filesystem helpers for custom 'struct file's
Why do we need r/o bind mounts?

This feature allows a read-only view into a read-write filesystem.  In the
process of doing that, it also provides infrastructure for keeping track of
the number of writers to any given mount.

This has a number of uses.  It allows chroots to have parts of filesystems
writable.  It will be useful for containers in the future because users may
have root inside a container, but should not be allowed to write to
somefilesystems.  This also replaces patches that vserver has had out of the
tree for several years.

It allows security enhancement by making sure that parts of your filesystem
read-only (such as when you don't trust your FTP server), when you don't want
to have entire new filesystems mounted, or when you want atime selectively
updated.  I've been using the following script to test that the feature is
working as desired.  It takes a directory and makes a regular bind and a r/o
bind mount of it.  It then performs some normal filesystem operations on the
three directories, including ones that are expected to fail, like creating a
file on the r/o mount.

This patch:

Some filesystems forego the vfs and may_open() and create their own 'struct
file's.

This patch creates a couple of helper functions which can be used by these
filesystems, and will provide a unified place which the r/o bind mount code
may patch.

Also, rename an existing, static-scope init_file() to a less generic name.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:43:04 -07:00
Cedric Le Goater a08b4be74c ipc namespace: remove config ipc ns fix
Finish the work : kill all #ifdef CONFIG_IPC_NS.

Thanks Robert !

Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Cc: Eric Biederman <ebiederm@xmision.com>
Cc: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:57 -07:00
Adrian Bunk d823e3e754 ipc/shm.c: make 2 functions static
This patch makes two needlessly global functions static.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:50 -07:00
Christoph Lameter 4ba9b9d0ba Slab API: remove useless ctor parameter and reorder parameters
Slab constructors currently have a flags parameter that is never used.  And
the order of the arguments is opposite to other slab functions.  The object
pointer is placed before the kmem_cache pointer.

Convert

        ctor(void *object, struct kmem_cache *s, unsigned long flags)

to

        ctor(struct kmem_cache *s, void *object)

throughout the kernel

[akpm@linux-foundation.org: coupla fixes]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:45 -07:00
Denis V. Lunev 7ee015e0fa [NET]: cleanup 3rd argument in netlink_sendskb
netlink_sendskb does not use third argument. Clean it and save a couple of
bytes.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 21:14:03 -07:00
Pavel Emelianov 7be77e20d5 Fix user struct leakage with locked IPC shem segment
When user locks an ipc shmem segmant with SHM_LOCK ctl and the segment is
already locked the shmem_lock() function returns 0.  After this the
subsequent code leaks the existing user struct:

== ipc/shm.c: sys_shmctl() ==
     ...
     err = shmem_lock(shp->shm_file, 1, user);
     if (!err) {
          shp->shm_perm.mode |= SHM_LOCKED;
          shp->mlock_user = user;
     }
     ...
==

Other results of this are:
1. the new shp->mlock_user is not get-ed and will point to freed
   memory when the task dies.
2. the RLIMIT_MEMLOCK is screwed on both user structs.

The exploit looks like this:

==
    id = shmget(...);
    setresuid(uid, 0, 0);
    shmctl(id, SHM_LOCK, NULL);
    setresuid(uid + 1, 0, 0);
    shmctl(id, SHM_LOCK, NULL);
==

My solution is to return 0 to the userspace and do not change the
segment's user.

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-31 15:39:40 -07:00
David Howells 2e92a3baee NOMMU: Fix SYSV IPC SHM
Fix the SYSV IPC SHM to work with the changes applied by the new fault handler
patches when CONFIG_MMU=n.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-31 15:39:36 -07:00
Paul Mundt 20c2df83d2 mm: Remove slab destructors from kmem_cache_create().
Slab destructors were no longer supported after Christoph's
c59def9f22 change. They've been
BUGs for both slab and slub, and slob never supported them
either.

This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-07-20 10:11:58 +09:00
Nick Piggin d0217ac04c mm: fault feedback #1
Change ->fault prototype.  We now return an int, which contains
VM_FAULT_xxx code in the low byte, and FAULT_RET_xxx code in the next byte.
 FAULT_RET_ code tells the VM whether a page was found, whether it has been
locked, and potentially other things.  This is not quite the way he wanted
it yet, but that's changed in the next patch (which requires changes to
arch code).

This means we no longer set VM_CAN_INVALIDATE in the vma in order to say
that a page is locked which requires filemap_nopage to go away (because we
can no longer remain backward compatible without that flag), but we were
going to do that anyway.

struct fault_data is renamed to struct vm_fault as Linus asked. address
is now a void __user * that we should firmly encourage drivers not to use
without really good reason.

The page is now returned via a page pointer in the vm_fault struct.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:41 -07:00
Nick Piggin 54cb8821de mm: merge populate and nopage into fault (fixes nonlinear)
Nonlinear mappings are (AFAIKS) simply a virtual memory concept that encodes
the virtual address -> file offset differently from linear mappings.

->populate is a layering violation because the filesystem/pagecache code
should need to know anything about the virtual memory mapping.  The hitch here
is that the ->nopage handler didn't pass down enough information (ie.  pgoff).
 But it is more logical to pass pgoff rather than have the ->nopage function
calculate it itself anyway (because that's a similar layering violation).

Having the populate handler install the pte itself is likewise a nasty thing
to be doing.

This patch introduces a new fault handler that replaces ->nopage and
->populate and (later) ->nopfn.  Most of the old mechanism is still in place
so there is a lot of duplication and nice cleanups that can be removed if
everyone switches over.

The rationale for doing this in the first place is that nonlinear mappings are
subject to the pagefault vs invalidate/truncate race too, and it seemed stupid
to duplicate the synchronisation logic rather than just consolidate the two.

After this patch, MAP_NONBLOCK no longer sets up ptes for pages present in
pagecache.  Seems like a fringe functionality anyway.

NOPAGE_REFAULT is removed.  This should be implemented with ->fault, and no
users have hit mainline yet.

[akpm@linux-foundation.org: cleanup]
[randy.dunlap@oracle.com: doc. fixes for readahead]
[akpm@linux-foundation.org: build fix]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:41 -07:00
Jeff Garzik 8e1c091ccc arch/i386/* fs/* ipc/*: mark variables with uninitialized_var()
Mark variables with uninitialized_var() if such a warning appears,
and analysis proves that the var is initialized properly on all paths
it is used.

Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-07-17 16:23:19 -04:00
Cedric Le Goater 7d69a1f4a7 remove CONFIG_UTS_NS and CONFIG_IPC_NS
CONFIG_UTS_NS and CONFIG_IPC_NS have very little value as they only
deactivate the unshare of the uts and ipc namespaces and do not improve
performance.

Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Acked-by: "Serge E. Hallyn" <serue@us.ibm.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Pavel Emelianov <xemul@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:47 -07:00
Alexander Graf d57d973101 fix logic error in ipc compat semctl()
When calling a semctl(IPC_STAT) without IPC_64 the check if the memory is
unevaluated.  This patch fixes this.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-06 10:23:43 -07:00
Eric W. Biederman 9d66586f77 shm: fix the filename of hugetlb sysv shared memory
Some user space tools need to identify SYSV shared memory when examining
/proc/<pid>/maps.  To do so they look for a block device with major zero, a
dentry named SYSV<sysv key>, and having the minor of the internal sysv
shared memory kernel mount.

To help these tools and to make it easier for people just browsing
/proc/<pid>/maps this patch modifies hugetlb sysv shared memory to use the
SYSV<key> dentry naming convention.

User space tools will still have to be aware that hugetlb sysv shared
memory lives on a different internal kernel mount and so has a different
block device minor number from the rest of sysv shared memory.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Albert Cahalan <acahalan@gmail.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-16 13:16:16 -07:00
Adam Litke 22741925d2 hugetlb: fix get_policy for stacked shared memory files
Here's another breakage as a result of shared memory stacked files :(

The NUMA policy for a VMA is determined by checking the following (in the
order given):

1) vma->vm_ops->get_policy() (if defined)
2) vma->vm_policy (if defined)
3) task->mempolicy (if defined)
4) Fall back to default_policy

By switching to stacked files for shared memory, get_policy() is now always
set to shm_get_policy which is a wrapper function.  This causes us to stop
at step 1, which yields NULL for hugetlb instead of task->mempolicy which
was the previous (and correct) result.

This patch modifies the shm_get_policy() wrapper to maintain steps 1-3 for
the wrapped vm_ops.

(akpm: the refcounting of mempolicies is busted and this patch does nothing to
improve it)

Signed-off-by: Adam Litke <agl@us.ibm.com>
Acked-by: William Irwin <bill.irwin@oracle.com>
Cc: dean gaudet <dean@arctic.org>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-16 13:16:16 -07:00
Badari Pulavarty 30475cc12a Restore shmid as inode# to fix /proc/pid/maps ABI breakage
shmid used to be stored as inode# for shared memory segments. Some of
the proc-ps tools use this from /proc/pid/maps.  Recent cleanups
to newseg() changed it.  This patch sets inode number back to shared
memory id to fix breakage.

Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Cc: "Albert Cahalan" <acahalan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-16 13:16:15 -07:00
Christoph Lameter a35afb830f Remove SLAB_CTOR_CONSTRUCTOR
SLAB_CTOR_CONSTRUCTOR is always specified. No point in checking it.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@ucw.cz>
Cc: David Chinner <dgc@sgi.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-17 05:23:04 -07:00
Amy Griffis 4fc03b9beb [PATCH] complete message queue auditing
Handle the edge cases for POSIX message queue auditing. Collect inode
info when opening an existing mq, and for send/receive operations. Remove
audit_inode_update() as it has really evolved into the equivalent of
audit_inode().

Signed-off-by: Amy Griffis <amy.griffis@hp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2007-05-11 05:38:26 -04:00
Randy Dunlap e63340ae6b header cleaning: don't include smp_lock.h when not used
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:07 -07:00
Badari Pulavarty e3222c4ecc Merge sys_clone()/sys_unshare() nsproxy and namespace handling
sys_clone() and sys_unshare() both makes copies of nsproxy and its associated
namespaces.  But they have different code paths.

This patch merges all the nsproxy and its associated namespace copy/clone
handling (as much as possible).  Posted on container list earlier for
feedback.

- Create a new nsproxy and its associated namespaces and pass it back to
  caller to attach it to right process.

- Changed all copy_*_ns() routines to return a new copy of namespace
  instead of attaching it to task->nsproxy.

- Moved the CAP_SYS_ADMIN checks out of copy_*_ns() routines.

- Removed unnessary !ns checks from copy_*_ns() and added BUG_ON()
  just incase.

- Get rid of all individual unshare_*_ns() routines and make use of
  copy_*_ns() instead.

[akpm@osdl.org: cleanups, warning fix]
[clg@fr.ibm.com: remove dup_namespaces() declaration]
[serue@us.ibm.com: fix CONFIG_IPC_NS=n, clone(CLONE_NEWIPC) retval]
[akpm@linux-foundation.org: fix build with CONFIG_SYSVIPC=n]
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: <containers@lists.osdl.org>
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:00 -07:00
Guy Streeter af7c693f14 Cap shmmax at INT_MAX in compat shminfo
The value of shmmax may be larger than will fit in the struct used by
the 32bit compat version of sys_shmctl. This change mirrors what the
normal sys_shmctl does when called with the old IPC_INFO command.

Signed-off-by: Guy Streeter <streeter@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:00 -07:00
Christoph Lameter 50953fe9e0 slab allocators: Remove SLAB_DEBUG_INITIAL flag
I have never seen a use of SLAB_DEBUG_INITIAL.  It is only supported by
SLAB.

I think its purpose was to have a callback after an object has been freed
to verify that the state is the constructor state again?  The callback is
performed before each freeing of an object.

I would think that it is much easier to check the object state manually
before the free.  That also places the check near the code object
manipulation of the object.

Also the SLAB_DEBUG_INITIAL callback is only performed if the kernel was
compiled with SLAB debugging on.  If there would be code in a constructor
handling SLAB_DEBUG_INITIAL then it would have to be conditional on
SLAB_DEBUG otherwise it would just be dead code.  But there is no such code
in the kernel.  I think SLUB_DEBUG_INITIAL is too problematic to make real
use of, difficult to understand and there are easier ways to accomplish the
same effect (i.e.  add debug code before kfree).

There is a related flag SLAB_CTOR_VERIFY that is frequently checked to be
clear in fs inode caches.  Remove the pointless checks (they would even be
pointless without removeal of SLAB_DEBUG_INITIAL) from the fs constructors.

This is the last slab flag that SLUB did not support.  Remove the check for
unimplemented flags from SLUB.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-07 12:12:57 -07:00
Serge E. Hallyn a28d193cbf [PATCH] ipcns: fix !CONFIG_IPC_NS behavior
When CONFIG_IPC_NS=n, clone(CLONE_NEWIPC) claims success, but did not actually
clone a new IPC namespace.

Fix this to return -EINVAL so the caller knows his request was denied.

Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-27 09:05:16 -07:00
Peter Zijlstra 7a434814c7 [PATCH] mqueue: nested locking annotation
Fix http://bugzilla.kernel.org/show_bug.cgi?id=8130

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-06 09:30:25 -08:00
Adam Litke 516dffdcd8 [PATCH] Fix get_unmapped_area and fsync for hugetlb shm segments
This patch provides the following hugetlb-related fixes to the recent stacked
shm files changes:
 - Update is_file_hugepages() so it will reconize hugetlb shm segments.
 - get_unmapped_area must be called with the nested file struct to handle
   the sfd->file->f_ops->get_unmapped_area == NULL case.
 - The fsync f_op must be wrapped since it is specified in the hugetlbfs
   f_ops.

This is based on proposed fixes from Eric Biederman that were debugged and
tested by me.  Without it, attempting to use hugetlb shared memory segments
on powerpc (and likely ia64) will kill your box.

Signed-off-by: Adam Litke <agl@us.ibm.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: William Irwin <bill.irwin@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-01 17:18:39 -08:00
Adrian Bunk de01bad2f5 [PATCH] make ipc/shm.c:shm_nopage() static
shm_nopage() can become static.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-01 14:53:35 -08:00
Eric W. Biederman bc56bba8f3 [PATCH] shm: make sysv ipc shared memory use stacked files
The current ipc shared memory code runs into several problems because it
does not quite use files like the rest of the kernel.  With the option of
backing ipc shared memory with either hugetlbfs or ordinary shared memory
the problems got worse.  With the added support for ipc namespaces things
behaved so unexpected that we now have several bad namespace reference
counting bugs when using what appears at first glance to be a reasonable
idiom.

So to attack these problems and hopefully make the code more maintainable
this patch simply uses the files provided by other parts of the kernel and
builds it's own files out of them.  The shm files are allocated in do_shmat
and freed when their reference count drops to zero with their last unmap.
The file and vm operations that we don't want to implement or we don't
implement completely we just delegate to the operations of our backing
file.

This means that we now get an accurate shm_nattch count for we have a
hugetlbfs inode for backing store, and the shm accounting of last attach
and last detach time work as well.

This means that getting a reference to the ipc namespace when we create the
file and dropping the referenece in the release method is now safe and
correct.

This means we no longer need a special case for clearing VM_MAYWRITE
as our file descriptor now only has write permissions when we have
requested write access when calling shmat.  Although VM_SHARED is now
cleared as well which I believe is harmless and is mostly likely a
minor bug fix.

By using the same set of operations for both the hugetlb case and regular
shared memory case shmdt is not simplified and made slightly more correct
as now the test "vma->vm_ops == &shm_vm_ops" is 100% accurate in spotting
all shared memory regions generated from sysvipc shared memory.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michal Piotrowski <michal.k.k.piotrowski@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-20 17:10:13 -08:00
Eric W. Biederman 0b4d414714 [PATCH] sysctl: remove insert_at_head from register_sysctl
The semantic effect of insert_at_head is that it would allow new registered
sysctl entries to override existing sysctl entries of the same name.  Which is
pain for caching and the proc interface never implemented.

I have done an audit and discovered that none of the current users of
register_sysctl care as (excpet for directories) they do not register
duplicate sysctl entries.

So this patch simply removes the support for overriding existing entries in
the sys_sysctl interface since no one uses it or cares and it makes future
enhancments harder.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Corey Minyard <minyard@acm.org>
Cc: Neil Brown <neilb@suse.de>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Jan Kara <jack@ucw.cz>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Cc: David Chinner <dgc@sgi.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-14 08:09:59 -08:00
Eric W. Biederman a5494dcd8b [PATCH] sysctl: move SYSV IPC sysctls to their own file
This is just a simple cleanup to keep kernel/sysctl.c from getting to crowded
with special cases, and by keeping all of the ipc logic to together it makes
the code a little more readable.

[gcoady.lk@gmail.com: build fix]
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Grant Coady <gcoady.lk@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-14 08:09:59 -08:00
Arjan van de Ven 92e1d5be91 [PATCH] mark struct inode_operations const 2
Many struct inode_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:46 -08:00
Arjan van de Ven 9a32144e9d [PATCH] mark struct file_operations const 7
Many struct file_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:46 -08:00
Eric W. Biederman bc1fc6d88c [PATCH] ipc: save the ipc namespace while reading proc files
The problem we were assuming that current->nsproxy->ipc_ns would never
change while someone has our file in /proc/sysvipc/ file open.  Given that
this can change with both unshare and by passing the file descriptor to
another process that assumption is occasionally wrong.

Therefore this patch causes /proc/sysvipc/* to cache the namespace and
increment it's count when we open the file and to decrement the count when
we close the file, ensuring consistent operation with no surprises.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:29 -08:00
Robert P. J. Day 72fd4a35a8 [PATCH] Numerous fixes to kernel-doc info in source files.
A variety of (mostly) innocuous fixes to the embedded kernel-doc content in
source files, including:

  * make multi-line initial descriptions single line
  * denote some function names, constants and structs as such
  * change erroneous opening '/*' to '/**' in a few places
  * reword some text for clarity

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:32 -08:00
Guy Streeter f66d45e99e [PATCH] correct sys_shmget allocation check
As written, sys_shmget will return ENOSPC when one page is still
available for allocation. This patch corrects the test.

Signed-off-by: Guy Streeter <guy.streeter+lkml@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
--
2007-01-23 11:18:50 -08:00
Robert P. J. Day 5cbded585d [PATCH] getting rid of all casts of k[cmz]alloc() calls
Run this:

	#!/bin/sh
	for f in $(grep -Erl "\([^\)]*\) *k[cmz]alloc" *) ; do
	  echo "De-casting $f..."
	  perl -pi -e "s/ ?= ?\([^\)]*\) *(k[cmz]alloc) *\(/ = \1\(/" $f
	done

And then go through and reinstate those cases where code is casting pointers
to non-pointers.

And then drop a few hunks which conflicted with outstanding work.

Cc: Russell King <rmk@arm.linux.org.uk>, Ian Molton <spyro@f2s.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Greg KH <greg@kroah.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Karsten Keil <kkeil@suse.de>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Ian Kent <raven@themaw.net>
Cc: Steven French <sfrench@us.ibm.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Jaroslav Kysela <perex@suse.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-13 09:05:58 -08:00
Josef Sipek 6d63079add [PATCH] struct path: convert ipc
Signed-off-by: Josef Sipek <jsipek@fsl.cs.sunysb.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:28:46 -08:00
Burman Yan 4668edc334 [PATCH] kernel core: replace kmalloc+memset with kzalloc
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:41 -08:00
suzuki 651971cb72 [PATCH] Fix the size limit of compat space msgsize
Currently we allocate 64k space on the user stack and use it the msgbuf for
sys_{msgrcv,msgsnd} for compat and the results are later copied in user [
by copy_in_user].  This patch introduces helper routines for
sys_{msgrcv,msgsnd} as below:

do_msgsnd() : Accepts the mtype and user space ptr to the buffer along with
the msqid and msgflg.

do_msgrcv() : Accepts a kernel space ptr to mtype and a userspace ptr to
the buffer.  The mtype has to be copied back the user space msgbuf by the
caller.

These changes avoid the need to allocate the msgsize on the userspace (
thus removing the size limt ) and the overhead of an extra copy_in_user().

Signed-off-by: Suzuki K P <suzuki@in.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:38 -08:00
Christoph Lameter e18b890bb0 [PATCH] slab: remove kmem_cache_t
Replace all uses of kmem_cache_t with struct kmem_cache.

The patch was generated using the following script:

	#!/bin/sh
	#
	# Replace one string by another in all the kernel sources.
	#

	set -e

	for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
		quilt add $file
		sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
		mv /tmp/$$ $file
		quilt refresh
	done

The script was run like this

	sh replace kmem_cache_t "struct kmem_cache"

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:25 -08:00
Christoph Lameter e94b176609 [PATCH] slab: remove SLAB_KERNEL
SLAB_KERNEL is an alias of GFP_KERNEL.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:24 -08:00
David Howells 65f27f3844 WorkStruct: Pass the work_struct pointer instead of context data
Pass the work_struct pointer to the work function rather than context data.
The work function can use container_of() to work out the data.

For the cases where the container of the work_struct may go away the moment the
pending bit is cleared, it is made possible to defer the release of the
structure by deferring the clearing of the pending bit.

To make this work, an extra flag is introduced into the management side of the
work_struct.  This governs auto-release of the structure upon execution.

Ordinarily, the work queue executor would release the work_struct for further
scheduling or deallocation by clearing the pending bit prior to jumping to the
work function.  This means that, unless the driver makes some guarantee itself
that the work_struct won't go away, the work function may not access anything
else in the work_struct or its container lest they be deallocated..  This is a
problem if the auxiliary data is taken away (as done by the last patch).

However, if the pending bit is *not* cleared before jumping to the work
function, then the work function *may* access the work_struct and its container
with no problems.  But then the work function must itself release the
work_struct by calling work_release().

In most cases, automatic release is fine, so this is the default.  Special
initiators exist for the non-auto-release case (ending in _NAR).


Signed-Off-By: David Howells <dhowells@redhat.com>
2006-11-22 14:55:48 +00:00
Linus Torvalds 80491eb90c Revert unintentional "volatile" changes in ipc/msg.c
Commit 5a06a363ef ("[PATCH] ipc/msg.c:
clean up coding style") breaks fakeroot on Alpha (variously hangs or
oopses), according to a report by Falk Hueffner.

The fact that the code seems to rely on compiler access ordering through
the use of "volatile" is a pretty certain sign that the code has locking
problems, and we should fix those properly and then remove the whole
"volatile" entirely.

But in the meantime, the movement of "volatile" was unintentional, and
should be reverted.

Cc: Falk Hueffner <falk@debian.org>
Cc: Andrew Morton <akpm@osdl.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-04 09:55:00 -08:00
Pavel Emelianov c7e12b8389 [PATCH] Fix ipc entries removal
Fix two issuses related to ipc_ids->entries freeing.

1. When freeing ipc namespace we need to free entries allocated
   with ipc_init_ids().

2. When removing old entries in grow_ary() ipc_rcu_putref()
   may be called on entries set to &ids->nullentry earlier in
   ipc_init_ids().
   This is almost impossible without namespaces, but with
   them this situation becomes possible.

Found during OpenVZ testing after obvious leaks in beancounters.

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Cc: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-03 12:27:56 -08:00
Michal Wronski f66e928b96 Michal Wronski: update contact info
My email has changed.

Signed-Off-By: Michal Wronski <michal.wronski@gmail.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-03 23:23:27 +02:00
Uwe Zeisberger f30c226954 fix file specification in comments
Many files include the filename at the beginning, serveral used a wrong one.

Signed-off-by: Uwe Zeisberger <Uwe_Zeisberger@digi.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-03 23:01:26 +02:00
Matt Helsley 2453a3062d [PATCH] ipc: replace kmalloc and memset in get_undo_list with kzalloc
Simplify get_undo_list() by dropping the unnecessary cast, removing the
size variable, and switching to kzalloc() instead of a kmalloc() followed
by a memset().

This cleanup was split then modified from Jes Sorenson's Task Notifiers
patches.

Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:22 -07:00
Kirill Korotaev 4e9823111b [PATCH] IPC namespace - shm
IPC namespace support for IPC shm code.

Signed-off-by: Pavel Emelianiov <xemul@openvz.org>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:22 -07:00
Kirill Korotaev e38935341a [PATCH] IPC namespace - sem
IPC namespace support for IPC sem code.

Signed-off-by: Pavel Emelianiov <xemul@openvz.org>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:22 -07:00
Kirill Korotaev 1e78693738 [PATCH] IPC namespace - msg
IPC namespace support for IPC msg code.

Signed-off-by: Pavel Emelianiov <xemul@openvz.org>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:22 -07:00
Kirill Korotaev 73ea41302b [PATCH] IPC namespace - utils
This patch adds basic IPC namespace functionality to
IPC utils:
- init_ipc_ns
- copy/clone/unshare/free IPC ns
- /proc preparations

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:22 -07:00
Cedric Le Goater a03fcb730b [PATCH] update mq_notify to use a struct pid
Message queues can signal a process waiting for a message.

This patch replaces the pid_t value with a struct pid to avoid pid wrap
around problems.

Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Acked-by: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:15 -07:00
Dave Hansen d8c76e6f45 [PATCH] r/o bind mount prepwork: inc_nlink() helper
This is mostly included for parity with dec_nlink(), where we will have some
more hooks.  This one should stay pretty darn straightforward for now.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01 00:39:30 -07:00
Dave Hansen 9a53c3a783 [PATCH] r/o bind mounts: unlink: monitor i_nlink
When a filesystem decrements i_nlink to zero, it means that a write must be
performed in order to drop the inode from the filesystem.

We're shortly going to have keep filesystems from being remounted r/o between
the time that this i_nlink decrement and that write occurs.

So, add a little helper function to do the decrements.  We'll tie into it in a
bit to note when i_nlink hits zero.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01 00:39:30 -07:00
Theodore Ts'o ba52de123d [PATCH] inode-diet: Eliminate i_blksize from the inode structure
This eliminates the i_blksize field from struct inode.  Filesystems that want
to provide a per-inode st_blksize can do so by providing their own getattr
routine instead of using the generic_fillattr() function.

Note that some filesystems were providing pretty much random (and incorrect)
values for i_blksize.

[bunk@stusta.de: cleanup]
[akpm@osdl.org: generic_fillattr() fix]
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:18 -07:00
Alexey Dobriyan 1a1d92c10d [PATCH] Really ignore kmem_cache_destroy return value
* Rougly half of callers already do it by not checking return value
* Code in drivers/acpi/osl.c does the following to be sure:

	(void)kmem_cache_destroy(cache);

* Those who check it printk something, however, slab_error already printed
  the name of failed cache.
* XFS BUGs on failed kmem_cache_destroy which is not the decision
  low-level filesystem driver should make. Converted to ignore.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:10 -07:00
Ingo Molnar 5a06a363ef [PATCH] ipc/msg.c: clean up coding style
Clean up ipc/msg.c to conform to Documentation/CodingStyle.  (before it was
an inconsistent hodepodge of various coding styles)

Verified that the before/after .o's are identical.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-31 13:28:44 -07:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Miklos Szeredi 75e1fcc0b1 [PATCH] vfs: add lock owner argument to flush operation
Pass the POSIX lock owner ID to the flush operation.

This is useful for filesystems which don't want to store any locking state
in inode->i_flock but want to handle locking/unlocking POSIX locks
internally.  FUSE is one such filesystem but I think it possible that some
network filesystems would need this also.

Also add a flag to indicate that a POSIX locking request was generated by
close(), so filesystems using the above feature won't send an extra locking
request in this case.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:43:02 -07:00
Hugh Dickins 185606fc6a [PATCH] remove unused o_flags from do_shmat
Remove the unused variable o_flags from do_shmat.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
David Howells 454e2398be [PATCH] VFS: Permit filesystem to override root dentry on mount
Extend the get_sb() filesystem operation to take an extra argument that
permits the VFS to pass in the target vfsmount that defines the mountpoint.

The filesystem is then required to manually set the superblock and root dentry
pointers.  For most filesystems, this should be done with simple_set_mnt()
which will set the superblock pointer and then set the root dentry to the
superblock's s_root (as per the old default behaviour).

The get_sb() op now returns an integer as there's now no need to return the
superblock pointer.

This patch permits a superblock to be implicitly shared amongst several mount
points, such as can be done with NFS to avoid potential inode aliasing.  In
such a case, simple_set_mnt() would not be called, and instead the mnt_root
and mnt_sb would be set directly.

The patch also makes the following changes:

 (*) the get_sb_*() convenience functions in the core kernel now take a vfsmount
     pointer argument and return an integer, so most filesystems have to change
     very little.

 (*) If one of the convenience function is not used, then get_sb() should
     normally call simple_set_mnt() to instantiate the vfsmount. This will
     always return 0, and so can be tail-called from get_sb().

 (*) generic_shutdown_super() now calls shrink_dcache_sb() to clean up the
     dcache upon superblock destruction rather than shrink_dcache_anon().

     This is required because the superblock may now have multiple trees that
     aren't actually bound to s_root, but that still need to be cleaned up. The
     currently called functions assume that the whole tree is rooted at s_root,
     and that anonymous dentries are not the roots of trees which results in
     dentries being left unculled.

     However, with the way NFS superblock sharing are currently set to be
     implemented, these assumptions are violated: the root of the filesystem is
     simply a dummy dentry and inode (the real inode for '/' may well be
     inaccessible), and all the vfsmounts are rooted on anonymous[*] dentries
     with child trees.

     [*] Anonymous until discovered from another tree.

 (*) The documentation has been adjusted, including the additional bit of
     changing ext2_* into foo_* in the documentation.

[akpm@osdl.org: convert ipath_fs, do other stuff]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:45 -07:00
George C. Wilson 20ca73bc79 [PATCH] Audit of POSIX Message Queue Syscalls v.2
This patch adds audit support to POSIX message queues.  It applies cleanly to
the lspp.b15 branch of Al Viro's git tree.  There are new auxiliary data
structures, and collection and emission routines in kernel/auditsc.c.  New hooks
in ipc/mqueue.c collect arguments from the syscalls.

I tested the patch by building the examples from the POSIX MQ library tarball.
Build them -lrt, not against the old MQ library in the tarball.  Here's the URL:
http://www.geocities.com/wronski12/posix_ipc/libmqueue-4.41.tar.gz
Do auditctl -a exit,always -S for mq_open, mq_timedsend, mq_timedreceive,
mq_notify, mq_getsetattr.  mq_unlink has no new hooks.  Please see the
corresponding userspace patch to get correct output from auditd for the new
record types.

[fixes folded]

Signed-off-by: George Wilson <ltcgcw@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-06-20 05:25:26 -04:00
Linda Knippers ac03221a4f [PATCH] update of IPC audit record cleanup
The following patch addresses most of the issues with the IPC_SET_PERM
records as described in:
https://www.redhat.com/archives/linux-audit/2006-May/msg00010.html
and addresses the comments I received on the record field names.

To summarize, I made the following changes:

1. Changed sys_msgctl() and semctl_down() so that an IPC_SET_PERM
   record is emitted in the failure case as well as the success case.
   This matches the behavior in sys_shmctl().  I could simplify the
   code in sys_msgctl() and semctl_down() slightly but it would mean
   that in some error cases we could get an IPC_SET_PERM record
   without an IPC record and that seemed odd.

2. No change to the IPC record type, given no feedback on the backward
   compatibility question.

3. Removed the qbytes field from the IPC record.  It wasn't being
   set and when audit_ipc_obj() is called from ipcperms(), the
   information isn't available.  If we want the information in the IPC
   record, more extensive changes will be necessary.  Since it only
   applies to message queues and it isn't really permission related, it
   doesn't seem worth it.

4. Removed the obj field from the IPC_SET_PERM record.  This means that
   the kern_ipc_perm argument is no longer needed.

5. Removed the spaces and renamed the IPC_SET_PERM field names.  Replaced iuid and
   igid fields with ouid and ogid in the IPC record.

I tested this with the lspp.22 kernel on an x86_64 box.  I believe it
applies cleanly on the latest kernel.

-- ljk

Signed-off-by: Linda Knippers <linda.knippers@hp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-06-20 05:25:24 -04:00
Steve Grubb 073115d6b2 [PATCH] Rework of IPC auditing
1) The audit_ipc_perms() function has been split into two different
functions:
        - audit_ipc_obj()
        - audit_ipc_set_perm()

There's a key shift here...  The audit_ipc_obj() collects the uid, gid,
mode, and SElinux context label of the current ipc object.  This
audit_ipc_obj() hook is now found in several places.  Most notably, it
is hooked in ipcperms(), which is called in various places around the
ipc code permforming a MAC check.  Additionally there are several places
where *checkid() is used to validate that an operation is being
performed on a valid object while not necessarily having a nearby
ipcperms() call.  In these locations, audit_ipc_obj() is called to
ensure that the information is captured by the audit system.

The audit_set_new_perm() function is called any time the permissions on
the ipc object changes.  In this case, the NEW permissions are recorded
(and note that an audit_ipc_obj() call exists just a few lines before
each instance).

2) Support for an AUDIT_IPC_SET_PERM audit message type.  This allows
for separate auxiliary audit records for normal operations on an IPC
object and permissions changes.  Note that the same struct
audit_aux_data_ipcctl is used and populated, however there are separate
audit_log_format statements based on the type of the message.  Finally,
the AUDIT_IPC block of code in audit_free_aux() was extended to handle
aux messages of this new type.  No more mem leaks I hope ;-)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-05-01 06:10:04 -04:00
Alexey Kuznetsov a9a5cd5d2a [PATCH] IPC: access to unmapped vmalloc area in grow_ary()
grow_ary() should not copy struct ipc_id_ary (it copies new->p, not
new). Due to this, memcpy() src pointer could hit unmapped vmalloc page
when near page boundary.

Found during OpenVZ stress testing

Signed-off-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-17 18:40:40 -07:00
Hugh Dickins b78b6af66a [PATCH] shmat: stop mprotect from giving write permission to a readonly attachment (CVE-2006-1524)
I found that all of 2.4 and 2.6 have been letting mprotect give write
permission to a readonly attachment of shared memory, whether or not IPC
would give the caller that permission.

SUS says "The behaviour of this function [mprotect] is unspecified if the
mapping was not established by a call to mmap", but I don't think we can
interpret that as allowing it to subvert IPC permissions.

I haven't tried 2.2, but the 2.2.26 source looks like it gets it right; and
the patch below reproduces that behaviour - mprotect cannot be used to add
write permission to a shared memory segment attached readonly.

This patch is simple, and I'm sure it's what we should have done in 2.4.0:
if you want to go on to switch write permission on and off with mprotect,
just don't attach the segment readonly in the first place.

However, we could have accumulated apps which attach readonly (even though
they would be permitted to attach read/write), and which subsequently use
mprotect to switch write permission on and off: it's not unreasonable.

I was going to add a second ipcperms check in do_shmat, to check for
writable when readonly, and if not writable find_vma and clear VM_MAYWRITE.
 But security_ipc_permission might do auditing, and it seems wrong to
report an attempt for write permission when there has been none.  Or we
could flag the vma as SHM, note the shmid or shp in vm_private_data, and
then get mprotect to check.

But the patch below is a lot simpler: I'd rather stick with it, if we can
convince ourselves somehow that it'll be safe.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-04-17 14:24:58 -07:00
Eric Sesterhenn 9ba025f108 BUG_ON() Conversion in ipc/shm.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner, contains unlikely() and can better optimized away.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-02 13:42:42 +02:00
Eric Sesterhenn 9bc98fc6fd BUG_ON() Conversion in ipc/util.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner, contains unlikely() and can better optimized away.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-04-01 01:20:23 +02:00
Serge E. Hallyn 7b7a317cf8 [PATCH] mqueue comment typo fix
(akpm: I don't do comment typos patches.  This one snuck through by accident)

Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 09:16:03 -08:00
Manfred Spraul 64bc0430ee [PATCH] one ipc/sem.c->mutex.c converstion too many..
Ingo's sem2mutex patch incorrectly replaced one reference to ipc/sem.c
with ipc/mutex.c in a comment.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 09:46:36 -08:00
Linus Torvalds 9ae21d1bb3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial:
  drivers/char/ftape/lowlevel/fdc-io.c: Correct a comment
  Kconfig help: MTD_JEDECPROBE already supports Intel
  Remove ugly debugging stuff
  do_mounts.c: Minor ROOT_DEV comment cleanup
  BUG_ON() Conversion in drivers/s390/block/dasd_devmap.c
  BUG_ON() Conversion in mm/mempool.c
  BUG_ON() Conversion in mm/memory.c
  BUG_ON() Conversion in kernel/fork.c
  BUG_ON() Conversion in ipc/sem.c
  BUG_ON() Conversion in fs/ext2/
  BUG_ON() Conversion in fs/hfs/
  BUG_ON() Conversion in fs/dcache.c
  BUG_ON() Conversion in fs/buffer.c
  BUG_ON() Conversion in input/serio/hp_sdc_mlc.c
  BUG_ON() Conversion in md/dm-table.c
  BUG_ON() Conversion in md/dm-path-selector.c
  BUG_ON() Conversion in drivers/isdn
  BUG_ON() Conversion in drivers/char
  BUG_ON() Conversion in drivers/mtd/
2006-03-26 09:41:18 -08:00
Ingo Molnar 5f921ae96f [PATCH] sem2mutex: ipc, id.sem
Semaphore to mutex conversion.

The conversion was generated via scripts, and the result was validated
automatically via a script as well.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:56:55 -08:00
Eric Sesterhenn 27315c96a4 BUG_ON() Conversion in ipc/sem.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner, contains unlikely() and can better optimized away.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-26 18:28:38 +02:00
Linus Torvalds 1b9a391736 Merge branch 'audit.b3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current
* 'audit.b3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current: (22 commits)
  [PATCH] fix audit_init failure path
  [PATCH] EXPORT_SYMBOL patch for audit_log, audit_log_start, audit_log_end and audit_format
  [PATCH] sem2mutex: audit_netlink_sem
  [PATCH] simplify audit_free() locking
  [PATCH] Fix audit operators
  [PATCH] promiscuous mode
  [PATCH] Add tty to syscall audit records
  [PATCH] add/remove rule update
  [PATCH] audit string fields interface + consumer
  [PATCH] SE Linux audit events
  [PATCH] Minor cosmetic cleanups to the code moved into auditfilter.c
  [PATCH] Fix audit record filtering with !CONFIG_AUDITSYSCALL
  [PATCH] Fix IA64 success/failure indication in syscall auditing.
  [PATCH] Miscellaneous bug and warning fixes
  [PATCH] Capture selinux subject/object context information.
  [PATCH] Exclude messages by message type
  [PATCH] Collect more inode information during syscall processing.
  [PATCH] Pass dentry, not just name, in fsnotify creation hooks.
  [PATCH] Define new range of userspace messages.
  [PATCH] Filter rule comparators
  ...

Fixed trivial conflict in security/selinux/hooks.c
2006-03-25 09:24:53 -08:00
Eric Sesterhenn 8cd5283b89 BUG_ON() Conversion in ipc/msg.c
this changes if() BUG(); constructs to BUG_ON() which is
cleaner, contains unlikely() and can better optimized away.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-24 18:44:22 +01:00
Hugh Dickins df1e2fb540 [PATCH] shmdt: check address alignment
SUSv3 says the shmdt() function shall fail with EINVAL if the value of
shmaddr is not the data segment start address of a shared memory segment:
our sys_shmdt needs to reject a shmaddr which is not page-aligned.

Does it have the potential to break existing apps?

Hugh says

  "sys_shmdt() just does the wrong (unexpected) thing with a misaligned
  address: it'll fail on what you might expect it to succeed on, and only
  succeed on what it should definitely fail on.

  "That is, I think it behaves as if shmaddr gets rounded up, when the only
  understandable behaviour would be if it rounded it down.

  "Which does mean you'd have to be devious to see anything but EINVAL from
  a misaligned shmaddr there, so it's not terribly important."

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24 07:33:25 -08:00
Michal Wronski a609164f7c Remove superfluous NOTIFY_COOKIE_LEN define
NOTIFY_COOKIE_LEN is defined in mqueue.h as well as mqueue.c
This patch removes redundant definition from mqueue.c

Signed-off-by: Michal Wronski <Michal.Wronski@motorola.com>
Signed-Off-By: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-22 00:34:37 +01:00