* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
NFS: Fix RCU issues in the NFSv4 delegation code
NFSv4: Fix the locking in nfs_inode_reclaim_delegation()
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2:
ocfs2: Avoid a gcc warning in ocfs2_wipe_inode().
ocfs2: Avoid direct write if we fall back to buffered I/O
ocfs2_dlmfs: Fix math error when reading LVB.
ocfs2: Update VFS inode's id info after reflink.
ocfs2: potential ERR_PTR dereference on error paths
ocfs2: Add directory entry later in ocfs2_symlink() and ocfs2_mknod()
ocfs2: use OCFS2_INODE_SKIP_ORPHAN_DIR in ocfs2_mknod error path
ocfs2: use OCFS2_INODE_SKIP_ORPHAN_DIR in ocfs2_symlink error path
ocfs2: add OCFS2_INODE_SKIP_ORPHAN_DIR flag and honor it in the inode wipe code
ocfs2: Reset status if we want to restart file extension.
ocfs2: Compute metaecc for superblocks during online resize.
ocfs2: Check the owner of a lockres inside the spinlock
ocfs2: one more warning fix in ocfs2_file_aio_write(), v2
ocfs2_dlmfs: User DLM_* when decoding file open flags.
gcc warns that a variable is uninitialized. It's actually handled, but
an early return fools gcc. Let's just initialize the variable to a
garbage value that will crash if the usage is ever broken.
Signed-off-by: Joel Becker <joel.becker@oracle.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
ceph: remove bad auth_x kmem_cache
ceph: fix lockless caps check
ceph: clear dir complete, invalidate dentry on replayed rename
ceph: fix direct io truncate offset
ceph: discard incoming messages with bad seq #
ceph: fix seq counting for skipped messages
ceph: add missing #includes
ceph: fix leaked spinlock during mds reconnect
ceph: print more useful version info on module load
ceph: fix snap realm splits
ceph: clear dir complete on d_move
It's useless, since our allocations are already a power of 2. And it was
allocated per-instance (not globally), which caused a name collision when
we tried to mount a second file system with auth_x enabled.
Signed-off-by: Sage Weil <sage@newdream.net>
If a rename operation is resent to the MDS following an MDS restart, the
client does not get a full reply (containing the resulting metadata) back.
In that case, a ceph_rename() needs to compensate by doing anything useful
that fill_inode() would have, like d_move().
It also needs to invalidate the dentry (to workaround the vfs_rename_dir()
bug) and clear the dir complete flag, just like fill_trace().
Signed-off-by: Sage Weil <sage@newdream.net>
We can get old message seq #'s after a tcp reconnect for stateful sessions
(i.e., the MDS). If we get a higher seq #, that is an error, and we
shouldn't see any bad seq #'s for stateless (mon, osd) connections.
Signed-off-by: Sage Weil <sage@newdream.net>
The snap realm split was checking i_snap_realm, not the list_head, to
determine if an inode belonged in the new realm. The check always failed,
which meant we always moved the inode, corrupting the old realm's list and
causing various crashes.
Also wait to release old realm reference to avoid possibility of use after
free.
Signed-off-by: Sage Weil <sage@newdream.net>
d_move() reorders the d_subdirs list, breaking the readdir result caching.
Unless/until d_move preserves that ordering, clear CEPH_I_COMPLETE on
rename.
Signed-off-by: Sage Weil <sage@newdream.net>
As of 32a88aa1, __sync_filesystem() will return 0 if s_bdi is not set.
And nilfs does not set s_bdi anywhere. I noticed this problem by the
warning introduced by the recent commit 5129a469 ("Catch filesystem
lacking s_bdi").
WARNING: at fs/super.c:959 vfs_kern_mount+0xc5/0x14e()
Hardware name: PowerEdge 2850
Modules linked in: nilfs2 loop tpm_tis tpm tpm_bios video shpchp pci_hotplug output dcdbas
Pid: 3773, comm: mount.nilfs2 Not tainted 2.6.34-rc6-debug #38
Call Trace:
[<c1028422>] warn_slowpath_common+0x60/0x90
[<c102845f>] warn_slowpath_null+0xd/0x10
[<c1095936>] vfs_kern_mount+0xc5/0x14e
[<c1095a03>] do_kern_mount+0x32/0xbd
[<c10a811e>] do_mount+0x671/0x6d0
[<c1073794>] ? __get_free_pages+0x1f/0x21
[<c10a684f>] ? copy_mount_options+0x2b/0xe2
[<c107b634>] ? strndup_user+0x48/0x67
[<c10a81de>] sys_mount+0x61/0x8f
[<c100280c>] sysenter_do_call+0x12/0x32
This ensures to set s_bdi for nilfs and fixes the sync silent failure.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix a number of RCU issues in the NFSv4 delegation code.
(1) delegation->cred doesn't need to be RCU protected as it's essentially an
invariant refcounted structure.
By the time we get to nfs_free_delegation(), the delegation is being
released, so no one else should be attempting to use the saved
credentials, and they can be cleared.
However, since the list of delegations could still be under traversal at
this point by such as nfs_client_return_marked_delegations(), the cred
should be released in nfs_do_free_delegation() rather than in
nfs_free_delegation(). Simply using rcu_assign_pointer() to clear it is
insufficient as that doesn't stop the cred from being destroyed, and nor
does calling put_rpccred() after call_rcu(), given that the latter is
asynchronous.
(2) nfs_detach_delegation_locked() and nfs_inode_set_delegation() should use
rcu_derefence_protected() because they can only be called if
nfs_client::cl_lock is held, and that guards against anyone changing
nfsi->delegation under it. Furthermore, the barrier imposed by
rcu_dereference() is superfluous, given that the spin_lock() is also a
barrier.
(3) nfs_detach_delegation_locked() is now passed a pointer to the nfs_client
struct so that it can issue lockdep advice based on clp->cl_lock for (2).
(4) nfs_inode_return_delegation_noreclaim() and nfs_inode_return_delegation()
should use rcu_access_pointer() outside the spinlocked region as they
merely examine the pointer and don't follow it, thus rendering unnecessary
the need to impose a partial ordering over the one item of interest.
These result in an RCU warning like the following:
[ INFO: suspicious rcu_dereference_check() usage. ]
---------------------------------------------------
fs/nfs/delegation.c:332 invoked rcu_dereference_check() without protection!
other info that might help us debug this:
rcu_scheduler_active = 1, debug_locks = 0
2 locks held by mount.nfs4/2281:
#0: (&type->s_umount_key#34){+.+...}, at: [<ffffffff810b25b4>] deactivate_super+0x60/0x80
#1: (iprune_sem){+.+...}, at: [<ffffffff810c332a>] invalidate_inodes+0x39/0x13a
stack backtrace:
Pid: 2281, comm: mount.nfs4 Not tainted 2.6.34-rc1-cachefs #110
Call Trace:
[<ffffffff8105149f>] lockdep_rcu_dereference+0xaa/0xb2
[<ffffffffa00b4591>] nfs_inode_return_delegation_noreclaim+0x5b/0xa0 [nfs]
[<ffffffffa0095d63>] nfs4_clear_inode+0x11/0x1e [nfs]
[<ffffffff810c2d92>] clear_inode+0x9e/0xf8
[<ffffffff810c3028>] dispose_list+0x67/0x10e
[<ffffffff810c340d>] invalidate_inodes+0x11c/0x13a
[<ffffffff810b1dc1>] generic_shutdown_super+0x42/0xf4
[<ffffffff810b1ebe>] kill_anon_super+0x11/0x4f
[<ffffffffa009893c>] nfs4_kill_super+0x3f/0x72 [nfs]
[<ffffffff810b25bc>] deactivate_super+0x68/0x80
[<ffffffff810c6744>] mntput_no_expire+0xbb/0xf8
[<ffffffff810c681b>] release_mounts+0x9a/0xb0
[<ffffffff810c689b>] put_mnt_ns+0x6a/0x79
[<ffffffffa00983a1>] nfs_follow_remote_path+0x5a/0x146 [nfs]
[<ffffffffa0098334>] ? nfs_do_root_mount+0x82/0x95 [nfs]
[<ffffffffa00985a9>] nfs4_try_mount+0x75/0xaf [nfs]
[<ffffffffa0098874>] nfs4_get_sb+0x291/0x31a [nfs]
[<ffffffff810b2059>] vfs_kern_mount+0xb8/0x177
[<ffffffff810b2176>] do_kern_mount+0x48/0xe8
[<ffffffff810c810b>] do_mount+0x782/0x7f9
[<ffffffff810c8205>] sys_mount+0x83/0xbe
[<ffffffff81001eeb>] system_call_fastpath+0x16/0x1b
Also on:
fs/nfs/delegation.c:215 invoked rcu_dereference_check() without protection!
[<ffffffff8105149f>] lockdep_rcu_dereference+0xaa/0xb2
[<ffffffffa00b4223>] nfs_inode_set_delegation+0xfe/0x219 [nfs]
[<ffffffffa00a9c6f>] nfs4_opendata_to_nfs4_state+0x2c2/0x30d [nfs]
[<ffffffffa00aa15d>] nfs4_do_open+0x2a6/0x3a6 [nfs]
...
And:
fs/nfs/delegation.c:40 invoked rcu_dereference_check() without protection!
[<ffffffff8105149f>] lockdep_rcu_dereference+0xaa/0xb2
[<ffffffffa00b3bef>] nfs_free_delegation+0x3d/0x6e [nfs]
[<ffffffffa00b3e71>] nfs_do_return_delegation+0x26/0x30 [nfs]
[<ffffffffa00b406a>] __nfs_inode_return_delegation+0x1ef/0x1fe [nfs]
[<ffffffffa00b448a>] nfs_client_return_marked_delegations+0xc9/0x124 [nfs]
...
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Ensure that we correctly rcu-dereference the delegation itself, and that we
protect against removal while we're changing the contents.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
when we fall back to buffered write from direct write, we call
__generic_file_aio_write() but that will end up doing direct write
even we are only prepared to do buffered write because the file
has the O_DIRECT flag set. This is a fix for
https://bugzilla.novell.com/show_bug.cgi?id=591039
revised with Joel's comments.
Signed-off-by: Li Dongyang <lidongyang@novell.com>
Acked-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
CONFIG_INOTIFY_USER defined but CONFIG_ANON_INODES undefined will result
in the following build failure:
LD vmlinux
fs/built-in.o: In function 'sys_inotify_init1':
(.text.sys_inotify_init1+0x22c): undefined reference to 'anon_inode_getfd'
fs/built-in.o: In function `sys_inotify_init1':
(.text.sys_inotify_init1+0x22c): relocation truncated to fit: R_MIPS_26 against 'anon_inode_getfd'
make[2]: *** [vmlinux] Error 1
make[1]: *** [sub-make] Error 2
make: *** [all] Error 2
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
exofs: Fix "add bdi backing to mount session" fall out
fs: fs/super.c needs to include backing-dev.h for !CONFIG_BLOCK
On low memory boxes or those with highmem, kernel can OOM before the
background reclaims inodes via xfssyncd. Add a shrinker to run inode
reclaim so that it inode reclaim is expedited when memory is low.
This is more complex than it needs to be because the VM folk don't
want a context added to the shrinker infrastructure. Hence we need
to add a global list of XFS mount structures so the shrinker can
traverse them.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The patch: add bdi backing to mount session
(b3d0ab7e60)
Has a bug in the placement of the bdi member at
struct exofs_sb_info. The layout member must be kept
last.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
When CONFIG_BLOCK is set, it ends up getting backing-dev.h included.
But for !CONFIG_BLOCK, it isn't so lucky. The proper thing to do is
include <linux/backing-dev.h> directly from the file it's used from,
so do that.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
nfs: fix memory leak in nfs_get_sb with CONFIG_NFS_V4
nfs: fix some issues in nfs41_proc_reclaim_complete()
NFS: Ensure that nfs_wb_page() waits for Pg_writeback to clear
NFS: Fix an unstable write data integrity race
nfs: testing for null instead of ERR_PTR()
NFS: rsize and wsize settings ignored on v4 mounts
NFSv4: Don't attempt an atomic open if the file is a mountpoint
SUNRPC: Fix a bug in rpcauth_prune_expired
The pktcdvd driver uses proper locking and does not need the BKL in the
ioctl and llseek functions of the character device, so kill both.
Moving the compat_ioctl handling from common code into the driver itself
fixes build problems when CONFIG_BLOCK is disabled.
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit b3d0ab7e60 ("exofs: add bdi backing
to mount session") has a bug in the placement of the bdi member at
struct exofs_sb_info. The layout member must be kept last.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If dentry found stale happens to be a root of disconnected tree, we
can't d_drop() it; its d_hash is actually part of s_anon and d_drop()
would simply hide it from shrink_dcache_for_umount(), leading to
all sorts of fun, including busy inodes on umount and oopsen after
that.
Bug had been there since at least 2006 (commit c636eb already has it),
so it's definitely -stable fodder.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The original code passed an ERR_PTR() to rpc_put_task() and instead of
returning zero on success it returned -ENOMEM.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
coda: move backing-dev.h kernel include inside __KERNEL__
mtd: ensure that bdi entries are properly initialized and registered
Move mtd_bdi_*mappable to mtdcore.c
btrfs: convert to using bdi_setup_and_register()
Catch filesystems lacking s_bdi
drbd: Terminate a connection early if sending the protocol fails
drbd: fix memory leak
Fix JFFS2 sync silent failure
smbfs: add bdi backing to mount session
ncpfs: add bdi backing to mount session
exofs: add bdi backing to mount session
ecryptfs: add bdi backing to mount session
coda: add bdi backing to mount session
cifs: add bdi backing to mount session
afs: add bdi backing to mount session.
9p: add bdi backing to mount session
bdi: add helper function for doing init and register of a bdi for a file system
block: ensure jiffies wrap is handled correctly in blk_rq_timed_out_timer
Neil Brown reports that he is seeing the BUG_ON(ret == 0) trigger in
nfs_page_async_flush. According to the trace in
https://bugzilla.novell.com/show_bug.cgi?id=599628
the problem appears to be due to nfs_wb_page() not waiting for the
PG_writeback flag to clear.
There is a ditto problem in nfs_wb_page_cancel()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The checks for CONFIG_MMU at this location are duplicated as all the code is
located inside a #ifndef CONFIG_MMU block. So the first conditional block will
always be included while the second never will.
Signed-off-by: Christoph Egger <siccegge@stud.informatik.uni-erlangen.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When read_buf is called to move over to the next page in the pagelist
of an NFSv4 request, it sets argp->end to essentially a random
number, certainly not an address within the page which argp->p now
points to. So subsequent calls to READ_BUF will think there is much
more than a page of spare space (the cast to u32 ensures an unsigned
comparison) so we can expect to fall off the end of the second
page.
We never encountered thsi in testing because typically the only
operations which use more than two pages are write-like operations,
which have their own decoding logic. Something like a getattr after a
write may cross a page boundary, but it would be very unusual for it to
cross another boundary after that.
Cc: stable@kernel.org
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
A new xfsqa test (226) with a prototype xfs_fsr change to try to
handle dynamic fork offsets better triggers an assertion failure
where the inode data fork is in btree format, yet there is room in
the inode for it to be in extent format. The two inodes look like:
before: ino 0x101 (target), num_extents 11, Max in-fork extents 6, broot size 40, fork offset 96
before: ino 0x115 (temp), num_extents 5, Max in-fork extents 3, broot size 40, fork offset 56
after: ino 0x101 (target), num_extents 5, Max in-fork extents 6, broot size 40, fork offset 96
after: ino 0x115 (temp), num_extents 11, Max in-fork extents 3, broot size 40, fork offset 56
Basically the target inode ends up with 5 extents in btree format,
but it had space for 6 extents in extent format, so ends up
incorrect. Notably here the broot size is the same, and that is
where the kernel code is going wrong - the btree root will fit, so
it lets the swap go ahead.
The check should not allow the swap to take place if the number of
extents while in btree format is less than the number of extents
that can fit in the inode in extent format. Adding that check will
prevent this swap and corruption from occurring.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: Issue the discard operation *before* releasing the blocks to be reused
ext4: Fix buffer head leaks after calls to ext4_get_inode_loc()
ext4: Fix possible lost inode write in no journal mode
noop_backing_dev_info is used only as a flag to mark filesystems that
don't have any backing store, like tmpfs, procfs, spufs, etc.
Signed-off-by: Joern Engel <joern@logfs.org>
Changed the BUG_ON() to a WARN_ON(). Note that adding dirty inodes
to the noop_backing_dev_info is not legal and will not result in
them being flushed, but we already catch this condition in
__mark_inode_dirty() when checking for a registered bdi.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Sizing the buffer based on block size is incorrect, leading
to a potential buffer over-run on 4K block size file systems
(because the metadata block size is always 8K). This bug
doesn't seem have triggered because 4K block size file systems
are not default, and also because metadata blocks after
compression tend to be less than 4K.
Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
Fix warn_on triggered by mounting a fsfuzzer corrupted file system, where
the root inode has been corrupted.
Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
Reported-by: Steve Grubb <sgrubb@redhat.com>
We are seeing a large regression in database performance on recent
kernels. The database opens a block device with O_DIRECT|O_SYNC and a
number of threads write to different regions of the file at the same time.
A simple test case is below. I haven't defined DEVICE since getting it
wrong will destroy your data :) On an 3 disk LVM with a 64k chunk size we
see about 17MB/sec and only a few threads in IO wait:
procs -----io---- -system-- -----cpu------
r b bi bo in cs us sy id wa st
0 3 0 16170 656 2259 0 0 86 14 0
0 2 0 16704 695 2408 0 0 92 8 0
0 2 0 17308 744 2653 0 0 86 14 0
0 2 0 17933 759 2777 0 0 89 10 0
Most threads are blocking in vfs_fsync_range, which has:
mutex_lock(&mapping->host->i_mutex);
err = fop->fsync(file, dentry, datasync);
if (!ret)
ret = err;
mutex_unlock(&mapping->host->i_mutex);
commit 148f948ba8 (vfs: Introduce new
helpers for syncing after writing to O_SYNC file or IS_SYNC inode) offers
some explanation of what is going on:
Use these new helpers for syncing from generic VFS functions. This makes
O_SYNC writes to block devices acquire i_mutex for syncing. If we really
care about this, we can make block_fsync() drop the i_mutex and reacquire
it before it returns.
Thanks Jan for such a good commit message! As well as dropping i_mutex,
Christoph suggests we should remove the call to sync_blockdev():
> sync_blockdev is an overcomplicated alias for filemap_write_and_wait on
> the block device inode, which is exactly what we did just before calling
> into ->fsync
The patch below incorporates both suggestions. With it the testcase improves
from 17MB/s to 68M/sec:
procs -----io---- -system-- -----cpu------
r b bi bo in cs us sy id wa st
0 7 0 65536 1000 3878 0 0 70 30 0
0 34 0 69632 1016 3921 0 1 46 53 0
0 57 0 69632 1000 3921 0 0 55 45 0
0 53 0 69640 754 4111 0 0 81 19 0
Testcase:
#define _GNU_SOURCE
#include <stdio.h>
#include <pthread.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#define NR_THREADS 64
#define BUFSIZE (64 * 1024)
#define DEVICE "/dev/mapper/XXXXXX"
#define ALIGN(VAL, SIZE) (((VAL)+(SIZE)-1) & ~((SIZE)-1))
static int fd;
static void *doit(void *arg)
{
unsigned long offset = (long)arg;
char *b, *buf;
b = malloc(BUFSIZE + 1024);
buf = (char *)ALIGN((unsigned long)b, 1024);
memset(buf, 0, BUFSIZE);
while (1)
pwrite(fd, buf, BUFSIZE, offset);
}
int main(int argc, char *argv[])
{
int flags = O_RDWR|O_DIRECT;
int i;
unsigned long offset = 0;
if (argc > 1 && !strcmp(argv[1], "O_SYNC"))
flags |= O_SYNC;
fd = open(DEVICE, flags);
if (fd == -1) {
perror("open");
exit(1);
}
for (i = 0; i < NR_THREADS-1; i++) {
pthread_t tid;
pthread_create(&tid, NULL, doit, (void *)offset);
offset += BUFSIZE;
}
doit((void *)offset);
return 0;
}
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Jan Kara <jack@suse.cz>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 48b32a3553 ("reiserfs: use generic
xattr handlers") introduced a problem that causes corruption when extended
attributes are replaced with a smaller value.
The issue is that the reiserfs_setattr to shrink the xattr file was moved
from before the write to after the write.
The root issue has always been in the reiserfs xattr code, but was papered
over by the fact that in the shrink case, the file would just be expanded
again while the xattr was written.
The end result is that the last 8 bytes of xattr data are lost.
This patch fixes it to use new_size.
Addresses https://bugzilla.kernel.org/show_bug.cgi?id=14826
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reported-by: Christian Kujau <lists@nerdbynature.de>
Tested-by: Christian Kujau <lists@nerdbynature.de>
Cc: Edward Shishkin <edward.shishkin@gmail.com>
Cc: Jethro Beekman <kernel@jbeekman.nl>
Cc: Greg Surbey <gregsurbey@hotmail.com>
Cc: Marco Gatti <marco.gatti@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 677c9b2e39 ("reiserfs: remove
privroot hiding in lookup") removed the magic from the lookup code to hide
the .reiserfs_priv directory since it was getting loaded at mount-time
instead. The intent was that the entry would be hidden from the user via
a poisoned d_compare, but this was faulty.
This introduced a security issue where unprivileged users could access and
modify extended attributes or ACLs belonging to other users, including
root.
This patch resolves the issue by properly hiding .reiserfs_priv. This was
the intent of the xattr poisoning code, but it appears to have never
worked as expected. This is fixed by using d_revalidate instead of
d_compare.
This patch makes -oexpose_privroot a no-op. I'm fine leaving it this way.
The effort involved in working out the corner cases wrt permissions and
caching outweigh the benefit of the feature.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Acked-by: Edward Shishkin <edward.shishkin@gmail.com>
Reported-by: Matt McCutchen <matt@mattmccutchen.net>
Tested-by: Matt McCutchen <matt@mattmccutchen.net>
Cc: Frederic Weisbecker <fweisbec@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>
David Woodhouse