Commit Graph

858 Commits

Author SHA1 Message Date
David Howells 09570f9149 proc: make struct proc_dir_entry::name a terminal array rather than a pointer
Since __proc_create() appends the name it is given to the end of the PDE
structure that it allocates, there isn't a need to store a name pointer.
Instead we can just replace the name pointer with a terminal char array of
_unspecified_ length.  The compiler will simply append the string to statically
defined variables of PDE type overlapping any hole at the end of the structure
and, unlike specifying an explicitly _zero_ length array, won't give a warning
if you try to statically initialise it with a string of more than zero length.

Also, whilst we're at it:

 (1) Move namelen to end just prior to name and reduce it to a single byte
     (name shouldn't be longer than NAME_MAX).

 (2) Move pde_unload_lock two places further on so that if it's four bytes in
     size on a 64-bit machine, it won't cause an unused hole in the PDE struct.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-27 12:50:45 -07:00
Arun Sharma 60063497a9 atomic: use <linux/atomic.h>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:47 -07:00
Vasiliy Kulikov 293eb1e777 proc: fix a race in do_io_accounting()
If an inode's mode permits opening /proc/PID/io and the resulting file
descriptor is kept across execve() of a setuid or similar binary, the
ptrace_may_access() check tries to prevent using this fd against the
task with escalated privileges.

Unfortunately, there is a race in the check against execve().  If
execve() is processed after the ptrace check, but before the actual io
information gathering, io statistics will be gathered from the
privileged process.  At least in theory this might lead to gathering
sensible information (like ssh/ftp password length) that wouldn't be
available otherwise.

Holding task->signal->cred_guard_mutex while gathering the io
information should protect against the race.

The order of locking is similar to the one inside of ptrace_attach():
first goes cred_guard_mutex, then lock_task_sighand().

Signed-off-by: Vasiliy Kulikov <segoon@openwall.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>
2011-07-26 16:49:43 -07:00
Daisuke Ogino d2857e79a2 procfs: return ENOENT on opening a being-removed proc entry
Change the return value to ENOENT.  This return value is then returned
when opening the proc entry that have been removed.  For example,
open("/proc/bus/pci/XX/YY") when the corresponding device is being
hot-removed.

Signed-off-by: Daisuke Ogino <ogino.daisuke@jp.fujitsu.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: Alexey Dobriyan <adobriyan@gmail.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>
2011-07-26 16:49:43 -07:00
David Rientjes be8f684d73 oom: make deprecated use of oom_adj more verbose
/proc/pid/oom_adj is deprecated and scheduled for removal in August 2012
according to Documentation/feature-removal-schedule.txt.

This patch makes the warning more verbose by making it appear as a more
serious problem (the presence of a stack trace and being multiline should
attract more attention) so that applications still using the old interface
can get fixed.

Very popular users of the old interface have been converted since the oom
killer rewrite has been introduced.  udevd switched to the
/proc/pid/oom_score_adj interface for v162, kde switched in 4.6.1, and
opensshd switched in 5.7p1.

At the start of 2012, this should be changed into a WARN() to emit all
such incidents and then finally remove the tunable in August 2012 as
scheduled.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: 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>
2011-07-25 20:57:09 -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
Linus Torvalds 8209f53d79 Merge branch 'ptrace' of git://git.kernel.org/pub/scm/linux/kernel/git/oleg/misc
* 'ptrace' of git://git.kernel.org/pub/scm/linux/kernel/git/oleg/misc: (39 commits)
  ptrace: do_wait(traced_leader_killed_by_mt_exec) can block forever
  ptrace: fix ptrace_signal() && STOP_DEQUEUED interaction
  connector: add an event for monitoring process tracers
  ptrace: dont send SIGSTOP on auto-attach if PT_SEIZED
  ptrace: mv send-SIGSTOP from do_fork() to ptrace_init_task()
  ptrace_init_task: initialize child->jobctl explicitly
  has_stopped_jobs: s/task_is_stopped/SIGNAL_STOP_STOPPED/
  ptrace: make former thread ID available via PTRACE_GETEVENTMSG after PTRACE_EVENT_EXEC stop
  ptrace: wait_consider_task: s/same_thread_group/ptrace_reparented/
  ptrace: kill real_parent_is_ptracer() in in favor of ptrace_reparented()
  ptrace: ptrace_reparented() should check same_thread_group()
  redefine thread_group_leader() as exit_signal >= 0
  do not change dead_task->exit_signal
  kill task_detached()
  reparent_leader: check EXIT_DEAD instead of task_detached()
  make do_notify_parent() __must_check, update the callers
  __ptrace_detach: avoid task_detached(), check do_notify_parent()
  kill tracehook_notify_death()
  make do_notify_parent() return bool
  ptrace: s/tracehook_tracer_task()/ptrace_parent()/
  ...
2011-07-22 15:06:50 -07:00
Kay Sievers f15146380d fs: seq_file - add event counter to simplify poll() support
Moving the event counter into the dynamically allocated 'struc seq_file'
allows poll() support without the need to allocate its own tracking
structure.

All current users are switched over to use the new counter.

Requested-by: Andrew Morton akpm@linux-foundation.org
Acked-by: NeilBrown <neilb@suse.de>
Tested-by: Lucas De Marchi lucas.demarchi@profusion.mobi
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 20:47:50 -04:00
Al Viro 10556cb21a ->permission() sanitizing: don't pass flags to ->permission()
not used by the instances anymore.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:24 -04:00
Al Viro 2830ba7f34 ->permission() sanitizing: don't pass flags to generic_permission()
redundant; all callers get it duplicated in mask & MAY_NOT_BLOCK and none of
them removes that bit.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:22 -04:00
Al Viro 1fc0f78ca9 ->permission() sanitizing: MAY_NOT_BLOCK
Duplicate the flags argument into mask bitmap.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:18 -04:00
Al Viro 178ea73521 kill check_acl callback of generic_permission()
its value depends only on inode and does not change; we might as
well store it in ->i_op->check_acl and be done with that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:16 -04:00
Vasiliy Kulikov 1d1221f375 proc: restrict access to /proc/PID/io
/proc/PID/io may be used for gathering private information.  E.g.  for
openssh and vsftpd daemons wchars/rchars may be used to learn the
precise password length.  Restrict it to processes being able to ptrace
the target process.

ptrace_may_access() is needed to prevent keeping open file descriptor of
"io" file, executing setuid binary and gathering io information of the
setuid'ed process.

Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-28 09:39:11 -07:00
Tejun Heo 06d984737b ptrace: s/tracehook_tracer_task()/ptrace_parent()/
tracehook.h is on the way out.  Rename tracehook_tracer_task() to
ptrace_parent() and move it from tracehook.h to ptrace.h.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2011-06-22 19:26:29 +02:00
Al Viro 1aec7036d0 proc_sys_permission() is OK in RCU mode
nothing blocking there, since all instances of sysctl
->permissions() method are non-blocking - both of them,
that is.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-06-20 10:45:25 -04:00
Al Viro cf12791116 proc_fd_permission() is doesn't need to bail out in RCU mode
nothing blocking except generic_permission()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-06-20 10:44:50 -04:00
Linus Torvalds 8b97b21e0f Merge git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/linux-2.6-nsfd
* git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/linux-2.6-nsfd:
  proc: Fix Oops on stat of /proc/<zombie pid>/ns/net
2011-06-16 15:02:20 -07:00
Eric W. Biederman 793925334f proc: Fix Oops on stat of /proc/<zombie pid>/ns/net
Don't call iput with the inode half setup to be a namespace filedescriptor.
Instead rearrange the code so that we don't initialize ei->ns_ops until
after I ns_ops->get succeeds, preventing us from invoking ns_ops->put
when ns_ops->get failed.

Reported-by: Ingo Saitz <Ingo.Saitz@stud.uni-hannover.de>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2011-06-15 14:35:29 -07:00
Al Viro ff78fca2a0 fix leak in proc_set_super()
set_anon_super() can fail...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-06-12 17:45:28 -04:00
Linus Torvalds 57ed609d4b Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile
* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  arch/tile: more /proc and /sys file support
2011-05-29 11:29:28 -07:00
Chris Metcalf f133ecca9c arch/tile: more /proc and /sys file support
This change introduces a few of the less controversial /proc and
/proc/sys interfaces for tile, along with sysfs attributes for
various things that were originally proposed as /proc/tile files.
It also adjusts the "hardwall" proc API.

Arnd Bergmann reviewed the initial arch/tile submission, which
included a complete set of all the /proc/tile and /proc/sys/tile
knobs that we had added in a somewhat ad hoc way during initial
development, and provided feedback on where most of them should go.

One knob turned out to be similar enough to the existing
/proc/sys/debug/exception-trace that it was re-implemented to use
that model instead.

Another knob was /proc/tile/grid, which reported the "grid" dimensions
of a tile chip (e.g. 8x8 processors = 64-core chip).  Arnd suggested
looking at sysfs for that, so this change moves that information
to a pair of sysfs attributes (chip_width and chip_height) in the
/sys/devices/system/cpu directory.  We also put the "chip_serial"
and "chip_revision" information from our old /proc/tile/board file
as attributes in /sys/devices/system/cpu.

Other information collected via hypervisor APIs is now placed in
/sys/hypervisor.  We create a /sys/hypervisor/type file (holding the
constant string "tilera") to be parallel with the Xen use of
/sys/hypervisor/type holding "xen".  We create three top-level files,
"version" (the hypervisor's own version), "config_version" (the
version of the configuration file), and "hvconfig" (the contents of
the configuration file).  The remaining information from our old
/proc/tile/board and /proc/tile/switch files becomes an attribute
group appearing under /sys/hypervisor/board/.

Finally, after some feedback from Arnd Bergmann for the previous
version of this patch, the /proc/tile/hardwall file is split up into
two conceptual parts.  First, a directory /proc/tile/hardwall/ which
contains one file per active hardwall, each file named after the
hardwall's ID and holding a cpulist that says which cpus are enclosed by
the hardwall.  Second, a /proc/PID file "hardwall" that is either
empty (for non-hardwall-using processes) or contains the hardwall ID.

Finally, this change pushes the /proc/sys/tile/unaligned_fixup/
directory, with knobs controlling the kernel code for handling the
fixup of unaligned exceptions.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2011-05-27 10:39:05 -04:00
Olaf Hering 997c136f51 fs/proc/vmcore.c: add hook to read_from_oldmem() to check for non-ram pages
The balloon driver in a Xen guest frees guest pages and marks them as
mmio.  When the kernel crashes and the crash kernel attempts to read the
oldmem via /proc/vmcore a read from ballooned pages will generate 100%
load in dom0 because Xen asks qemu-dm for the page content.  Since the
reads come in as 8byte requests each ballooned page is tried 512 times.

With this change a hook can be registered which checks wether the given
pfn is really ram.  The hook has to return a value > 0 for ram pages, a
value < 0 on error (because the hypercall is not known) and 0 for non-ram
pages.

This will reduce the time to read /proc/vmcore.  Without this change a
512M guest with 128M crashkernel region needs 200 seconds to read it, with
this change it takes just 2 seconds.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26 17:12:37 -07:00
KOSAKI Motohiro 98bc93e505 proc: fix pagemap_read() error case
Currently, pagemap_read() has three error and/or corner case handling
mistake.

 (1) If ppos parameter is wrong, mm refcount will be leak.
 (2) If count parameter is 0, mm refcount will be leak too.
 (3) If the current task is sleeping in kmalloc() and the system
     is out of memory and oom-killer kill the proc associated task,
     mm_refcount prevent the task free its memory. then system may
     hang up.

<Quote Hugh's explain why we shold call kmalloc() before get_mm()>

  check_mem_permission gets a reference to the mm.  If we
  __get_free_page after check_mem_permission, imagine what happens if the
  system is out of memory, and the mm we're looking at is selected for
  killing by the OOM killer: while we wait in __get_free_page for more
  memory, no memory is freed from the selected mm because it cannot reach
  exit_mmap while we hold that reference.

This patch fixes the above three.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jovi Zhang <bookjovi@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Stephen Wilson <wilsons@start.ca>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26 17:12:37 -07:00
KOSAKI Motohiro 30cd890391 proc: put check_mem_permission after __get_free_page in mem_write
It whould be better if put check_mem_permission after __get_free_page in
mem_write, to be same as function mem_read.

Hugh Dickins explained the reason.

    check_mem_permission gets a reference to the mm.  If we __get_free_page
    after check_mem_permission, imagine what happens if the system is out
    of memory, and the mm we're looking at is selected for killing by the
    OOM killer: while we wait in __get_free_page for more memory, no memory
    is freed from the selected mm because it cannot reach exit_mmap while
    we hold that reference.

Reported-by: Jovi Zhang <bookjovi@gmail.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Stephen Wilson <wilsons@start.ca>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26 17:12:37 -07:00
Yuanhan Liu a4dbf0ec2a proc/stat: use defined macro KMALLOC_MAX_SIZE
There is a macro for the max size kmalloc can allocate, so use it instead
of a hardcoded number.

Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.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>
2011-05-26 17:12:37 -07:00
Mike Frysinger e130aa70f4 proc: constify status array
No need for this local array to be writable, so mark it const.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26 17:12:36 -07:00
Alexey Dobriyan 0a8cb8e341 fs/proc: convert to kstrtoX()
Convert fs/proc/ from strict_strto*() to kstrto*() functions.

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>
2011-05-26 17:12:36 -07:00
Jiri Slaby 3864601387 mm: extract exe_file handling from procfs
Setup and cleanup of mm_struct->exe_file is currently done in fs/proc/.
This was because exe_file was needed only for /proc/<pid>/exe.  Since we
will need the exe_file functionality also for core dumps (so core name can
contain full binary path), built this functionality always into the
kernel.

To achieve that move that out of proc FS to the kernel/ where in fact it
should belong.  By doing that we can make dup_mm_exe_file static.  Also we
can drop linux/proc_fs.h inclusion in fs/exec.c and kernel/fork.c.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26 17:12:36 -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
Linus Torvalds 14d74e0cab Merge git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/linux-2.6-nsfd
* git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/linux-2.6-nsfd:
  net: fix get_net_ns_by_fd for !CONFIG_NET_NS
  ns proc: Return -ENOENT for a nonexistent /proc/self/ns/ entry.
  ns: Declare sys_setns in syscalls.h
  net: Allow setting the network namespace by fd
  ns proc: Add support for the ipc namespace
  ns proc: Add support for the uts namespace
  ns proc: Add support for the network namespace.
  ns: Introduce the setns syscall
  ns: proc files for namespace naming policy.
2011-05-25 18:10:16 -07:00
Linus Torvalds 3f5785ec31 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (89 commits)
  bonding: documentation and code cleanup for resend_igmp
  bonding: prevent deadlock on slave store with alb mode (v3)
  net: hold rtnl again in dump callbacks
  Add Fujitsu 1000base-SX PCI ID to tg3
  bnx2x: protect sequence increment with mutex
  sch_sfq: fix peek() implementation
  isdn: netjet - blacklist Digium TDM400P
  via-velocity: don't annotate MAC registers as packed
  xen: netfront: hold RTNL when updating features.
  sctp: fix memory leak of the ASCONF queue when free asoc
  net: make dev_disable_lro use physical device if passed a vlan dev (v2)
  net: move is_vlan_dev into public header file (v2)
  bug.h: Fix build with CONFIG_PRINTK disabled.
  wireless: fix fatal kernel-doc error + warning in mac80211.h
  wireless: fix cfg80211.h new kernel-doc warnings
  iwlagn: dbg_fixed_rate only used when CONFIG_MAC80211_DEBUGFS enabled
  dst: catch uninitialized metrics
  be2net: hash key for rss-config cmd not set
  bridge: initialize fake_rtable metrics
  net: fix __dst_destroy_metrics_generic()
  ...

Fix up trivial conflicts in drivers/staging/brcm80211/brcmfmac/wl_cfg80211.c
2011-05-25 17:00:17 -07:00
Stephen Wilson 5b52fc890b proc: allocate storage for numa_maps statistics once
In show_numa_map() we collect statistics into a numa_maps structure.
Since the number of NUMA nodes can be very large, this structure is not a
candidate for stack allocation.

Instead of going thru a kmalloc()+kfree() cycle each time show_numa_map()
is invoked, perform the allocation just once when /proc/pid/numa_maps is
opened.

Performing the allocation when numa_maps is opened, and thus before a
reference to the target tasks mm is taken, eliminates a potential
stalemate condition in the oom-killer as originally described by Hugh
Dickins:

  ... imagine what happens if the system is out of memory, and the mm
  we're looking at is selected for killing by the OOM killer: while
  we wait in __get_free_page for more memory, no memory is freed
  from the selected mm because it cannot reach exit_mmap while we hold
  that reference.

Signed-off-by: Stephen Wilson <wilsons@start.ca>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25 08:39:35 -07:00
Stephen Wilson f2beb79836 proc: make struct proc_maps_private truly private
Now that mm/mempolicy.c is no longer implementing /proc/pid/numa_maps
there is no need to export struct proc_maps_private to the world.  Move it
to fs/proc/internal.h instead.

Signed-off-by: Stephen Wilson <wilsons@start.ca>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25 08:39:35 -07:00
Stephen Wilson f69ff943df mm: proc: move show_numa_map() to fs/proc/task_mmu.c
Moving show_numa_map() from mempolicy.c to task_mmu.c solves several
issues.

  - Having the show() operation "miles away" from the corresponding
    seq_file iteration operations is a maintenance burden.

  - The need to export ad hoc info like struct proc_maps_private is
    eliminated.

  - The implementation of show_numa_map() can be improved in a simple
    manner by cooperating with the other seq_file operations (start,
    stop, etc) -- something that would be messy to do without this
    change.

Signed-off-by: Stephen Wilson <wilsons@start.ca>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25 08:39:34 -07:00
Eric W. Biederman 62ca24baf1 ns proc: Return -ENOENT for a nonexistent /proc/self/ns/ entry.
Spotted-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2011-05-24 15:30:33 -07:00
John W. Linville 31ec97d9ce Merge ssh://master.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6 into for-davem 2011-05-24 16:47:54 -04:00
Alexey Dobriyan 011159a0a7 airo: correct proc entry creation interfaces
* use proc_mkdir_mode() instead of create_proc_entry(S_IFDIR|...),
  export proc_mkdir_mode() for that, oh well.
* don't supply S_IFREG to proc_create_data(), it's unnecessary

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-05-16 14:25:28 -04:00
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
Eric W. Biederman 34482e89a5 ns proc: Add support for the uts namespace
Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2011-05-10 14:35:35 -07:00
Eric W. Biederman 13b6f57623 ns proc: Add support for the network namespace.
Implementing file descriptors for the network namespace
is simple and straight forward.

Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2011-05-10 14:34:26 -07:00
Eric W. Biederman 6b4e306aa3 ns: proc files for namespace naming policy.
Create files under /proc/<pid>/ns/ to allow controlling the
namespaces of a process.

This addresses three specific problems that can make namespaces hard to
work with.
- Namespaces require a dedicated process to pin them in memory.
- It is not possible to use a namespace unless you are the child
  of the original creator.
- Namespaces don't have names that userspace can use to talk about
  them.

The namespace files under /proc/<pid>/ns/ can be opened and the
file descriptor can be used to talk about a specific namespace, and
to keep the specified namespace alive.

A namespace can be kept alive by either holding the file descriptor
open or bind mounting the file someplace else.  aka:
mount --bind /proc/self/ns/net /some/filesystem/path
mount --bind /proc/self/fd/<N> /some/filesystem/path

This allows namespaces to be named with userspace policy.

It requires additional support to make use of these filedescriptors
and that will be comming in the following patches.

Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2011-05-10 14:31:44 -07:00
Mikulas Patocka a09a79f668 Don't lock guardpage if the stack is growing up
Linux kernel excludes guard page when performing mlock on a VMA with
down-growing stack. However, some architectures have up-growing stack
and locking the guard page should be excluded in this case too.

This patch fixes lvm2 on PA-RISC (and possibly other architectures with
up-growing stack). lvm2 calculates number of used pages when locking and
when unlocking and reports an internal error if the numbers mismatch.

[ Patch changed fairly extensively to also fix /proc/<pid>/maps for the
  grows-up case, and to move things around a bit to clean it all up and
  share the infrstructure with the /proc bits.

  Tested on ia64 that has both grow-up and grow-down segments  - Linus ]

Signed-off-by: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Tested-by: Tony Luck <tony.luck@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-09 16:22:07 -07:00
Linus Torvalds d8bdc59f21 proc: do proper range check on readdir offset
Rather than pass in some random truncated offset to the pid-related
functions, check that the offset is in range up-front.

This is just cleanup, the previous commit fixed the real problem.

Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-04-18 10:36:54 -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
Linus Torvalds 76597cd314 proc: fix oops on invalid /proc/<pid>/maps access
When m_start returns an error, the seq_file logic will still call m_stop
with that error entry, so we'd better make sure that we check it before
using it as a vma.

Introduced by commit ec6fd8a435 ("report errors in /proc/*/*map*
sanely"), which replaced NULL with various ERR_PTR() cases.

(On ia64, you happen to get a unaligned fault instead of a page fault,
since the address used is generally some random error code like -EPERM)

Reported-by: Anca Emanuel <anca.emanuel@gmail.com>
Reported-by: Tony Luck <tony.luck@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Américo Wang <xiyou.wangcong@gmail.com>
Cc: Stephen Wilson <wilsons@start.ca>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-27 19:09:29 -07:00
Linus Torvalds b81a618dcd 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:
  deal with races in /proc/*/{syscall,stack,personality}
  proc: enable writing to /proc/pid/mem
  proc: make check_mem_permission() return an mm_struct on success
  proc: hold cred_guard_mutex in check_mem_permission()
  proc: disable mem_write after exec
  mm: implement access_remote_vm
  mm: factor out main logic of access_process_vm
  mm: use mm_struct to resolve gate vma's in __get_user_pages
  mm: arch: rename in_gate_area_no_task to in_gate_area_no_mm
  mm: arch: make in_gate_area take an mm_struct instead of a task_struct
  mm: arch: make get_gate_vma take an mm_struct instead of a task_struct
  x86: mark associated mm when running a task in 32 bit compatibility mode
  x86: add context tag to mark mm when running a task in 32-bit compatibility mode
  auxv: require the target to be tracable (or yourself)
  close race in /proc/*/environ
  report errors in /proc/*/*map* sanely
  pagemap: close races with suid execve
  make sessionid permissions in /proc/*/task/* match those in /proc/*
  fix leaks in path_lookupat()

Fix up trivial conflicts in fs/proc/base.c
2011-03-23 20:51:42 -07:00
Oleg Nesterov 52e9fc76d0 procfs: kill the global proc_mnt variable
After the previous cleanup in proc_get_sb() the global proc_mnt has no
reasons to exists, kill it.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Serge E. Hallyn <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:58 -07:00
Eric W. Biederman 4308eebbeb pidns: call pid_ns_prepare_proc() from create_pid_namespace()
Reorganize proc_get_sb() so it can be called before the struct pid of the
first process is allocated.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Serge E. Hallyn <serge@hallyn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:58 -07:00
Kees Cook 5883f57ca0 proc: protect mm start_code/end_code in /proc/pid/stat
While mm->start_stack was protected from cross-uid viewing (commit
f83ce3e6b0 ("proc: avoid information leaks to non-privileged
processes")), the start_code and end_code values were not.  This would
allow the text location of a PIE binary to leak, defeating ASLR.

Note that the value "1" is used instead of "0" for a protected value since
"ps", "killall", and likely other readers of /proc/pid/stat, take
start_code of "0" to mean a kernel thread and will misbehave.  Thanks to
Brad Spengler for pointing this out.

Addresses CVE-2011-0726

Signed-off-by: Kees Cook <kees.cook@canonical.com>
Cc: <stable@kernel.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Eugene Teo <eugeneteo@kernel.sg>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Brad Spengler <spender@grsecurity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23 19:46:37 -07:00
Alexey Dobriyan 312ec7e50c proc: make struct proc_dir_entry::namelen unsigned int
1. namelen is declared "unsigned short" which hints for "maybe space savings".
   Indeed in 2.4 struct proc_dir_entry looked like:

        struct proc_dir_entry {
                unsigned short low_ino;
                unsigned short namelen;

   Now, low_ino is "unsigned int", all savings were gone for a long time.
   "struct proc_dir_entry" is not that countless to worry about it's size,
   anyway.

2. converting from unsigned short to int/unsigned int can only create
   problems, we better play it safe.

Space is not really conserved, because of natural alignment for the next
field.  sizeof(struct proc_dir_entry) remains the same.

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>
2011-03-23 19:46:37 -07:00