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43481 commits

Author SHA1 Message Date
Daniel Rosenberg
00ee836d89 fuse: Add support for d_canonical_path
Allows FUSE to report to inotify that it is acting
as a layered filesystem. The userspace component
returns a string representing the location of the
underlying file. If the string cannot be resolved
into a path, the top level path is returned instead.

bug: 23904372
Change-Id: Iabdca0bbedfbff59e9c820c58636a68ef9683d9f
Signed-off-by: Daniel Rosenberg <drosen@google.com>
2016-04-25 19:16:11 -07:00
Daniel Rosenberg
4b7de83752 vfs: change d_canonical_path to take two paths
bug: 23904372
Change-Id: I4a686d64b6de37decf60019be1718e1d820193e6
Signed-off-by: Daniel Rosenberg <drosen@google.com>
2016-04-25 19:15:48 -07:00
Alex Shi
bab1564182 Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android
Conflicts:
	d_canonical_path in include/linux/dcache.h
2016-04-21 14:08:44 +08:00
Filipe Manana
1653a3b0e9 Btrfs: fix file/data loss caused by fsync after rename and new inode
commit 56f23fdbb600e6087db7b009775b95ce07cc3195 upstream.

If we rename an inode A (be it a file or a directory), create a new
inode B with the old name of inode A and under the same parent directory,
fsync inode B and then power fail, at log tree replay time we end up
removing inode A completely. If inode A is a directory then all its files
are gone too.

Example scenarios where this happens:
This is reproducible with the following steps, taken from a couple of
test cases written for fstests which are going to be submitted upstream
soon:

   # Scenario 1

   mkfs.btrfs -f /dev/sdc
   mount /dev/sdc /mnt
   mkdir -p /mnt/a/x
   echo "hello" > /mnt/a/x/foo
   echo "world" > /mnt/a/x/bar
   sync
   mv /mnt/a/x /mnt/a/y
   mkdir /mnt/a/x
   xfs_io -c fsync /mnt/a/x
   <power failure happens>

   The next time the fs is mounted, log tree replay happens and
   the directory "y" does not exist nor do the files "foo" and
   "bar" exist anywhere (neither in "y" nor in "x", nor the root
   nor anywhere).

   # Scenario 2

   mkfs.btrfs -f /dev/sdc
   mount /dev/sdc /mnt
   mkdir /mnt/a
   echo "hello" > /mnt/a/foo
   sync
   mv /mnt/a/foo /mnt/a/bar
   echo "world" > /mnt/a/foo
   xfs_io -c fsync /mnt/a/foo
   <power failure happens>

   The next time the fs is mounted, log tree replay happens and the
   file "bar" does not exists anymore. A file with the name "foo"
   exists and it matches the second file we created.

Another related problem that does not involve file/data loss is when a
new inode is created with the name of a deleted snapshot and we fsync it:

   mkfs.btrfs -f /dev/sdc
   mount /dev/sdc /mnt
   mkdir /mnt/testdir
   btrfs subvolume snapshot /mnt /mnt/testdir/snap
   btrfs subvolume delete /mnt/testdir/snap
   rmdir /mnt/testdir
   mkdir /mnt/testdir
   xfs_io -c fsync /mnt/testdir # or fsync some file inside /mnt/testdir
   <power failure>

   The next time the fs is mounted the log replay procedure fails because
   it attempts to delete the snapshot entry (which has dir item key type
   of BTRFS_ROOT_ITEM_KEY) as if it were a regular (non-root) entry,
   resulting in the following error that causes mount to fail:

   [52174.510532] BTRFS info (device dm-0): failed to delete reference to snap, inode 257 parent 257
   [52174.512570] ------------[ cut here ]------------
   [52174.513278] WARNING: CPU: 12 PID: 28024 at fs/btrfs/inode.c:3986 __btrfs_unlink_inode+0x178/0x351 [btrfs]()
   [52174.514681] BTRFS: Transaction aborted (error -2)
   [52174.515630] Modules linked in: btrfs dm_flakey dm_mod overlay crc32c_generic ppdev xor raid6_pq acpi_cpufreq parport_pc tpm_tis sg parport tpm evdev i2c_piix4 proc
   [52174.521568] CPU: 12 PID: 28024 Comm: mount Tainted: G        W       4.5.0-rc6-btrfs-next-27+ #1
   [52174.522805] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
   [52174.524053]  0000000000000000 ffff8801df2a7710 ffffffff81264e93 ffff8801df2a7758
   [52174.524053]  0000000000000009 ffff8801df2a7748 ffffffff81051618 ffffffffa03591cd
   [52174.524053]  00000000fffffffe ffff88015e6e5000 ffff88016dbc3c88 ffff88016dbc3c88
   [52174.524053] Call Trace:
   [52174.524053]  [<ffffffff81264e93>] dump_stack+0x67/0x90
   [52174.524053]  [<ffffffff81051618>] warn_slowpath_common+0x99/0xb2
   [52174.524053]  [<ffffffffa03591cd>] ? __btrfs_unlink_inode+0x178/0x351 [btrfs]
   [52174.524053]  [<ffffffff81051679>] warn_slowpath_fmt+0x48/0x50
   [52174.524053]  [<ffffffffa03591cd>] __btrfs_unlink_inode+0x178/0x351 [btrfs]
   [52174.524053]  [<ffffffff8118f5e9>] ? iput+0xb0/0x284
   [52174.524053]  [<ffffffffa0359fe8>] btrfs_unlink_inode+0x1c/0x3d [btrfs]
   [52174.524053]  [<ffffffffa038631e>] check_item_in_log+0x1fe/0x29b [btrfs]
   [52174.524053]  [<ffffffffa0386522>] replay_dir_deletes+0x167/0x1cf [btrfs]
   [52174.524053]  [<ffffffffa038739e>] fixup_inode_link_count+0x289/0x2aa [btrfs]
   [52174.524053]  [<ffffffffa038748a>] fixup_inode_link_counts+0xcb/0x105 [btrfs]
   [52174.524053]  [<ffffffffa038a5ec>] btrfs_recover_log_trees+0x258/0x32c [btrfs]
   [52174.524053]  [<ffffffffa03885b2>] ? replay_one_extent+0x511/0x511 [btrfs]
   [52174.524053]  [<ffffffffa034f288>] open_ctree+0x1dd4/0x21b9 [btrfs]
   [52174.524053]  [<ffffffffa032b753>] btrfs_mount+0x97e/0xaed [btrfs]
   [52174.524053]  [<ffffffff8108e1b7>] ? trace_hardirqs_on+0xd/0xf
   [52174.524053]  [<ffffffff8117bafa>] mount_fs+0x67/0x131
   [52174.524053]  [<ffffffff81193003>] vfs_kern_mount+0x6c/0xde
   [52174.524053]  [<ffffffffa032af81>] btrfs_mount+0x1ac/0xaed [btrfs]
   [52174.524053]  [<ffffffff8108e1b7>] ? trace_hardirqs_on+0xd/0xf
   [52174.524053]  [<ffffffff8108c262>] ? lockdep_init_map+0xb9/0x1b3
   [52174.524053]  [<ffffffff8117bafa>] mount_fs+0x67/0x131
   [52174.524053]  [<ffffffff81193003>] vfs_kern_mount+0x6c/0xde
   [52174.524053]  [<ffffffff8119590f>] do_mount+0x8a6/0x9e8
   [52174.524053]  [<ffffffff811358dd>] ? strndup_user+0x3f/0x59
   [52174.524053]  [<ffffffff81195c65>] SyS_mount+0x77/0x9f
   [52174.524053]  [<ffffffff814935d7>] entry_SYSCALL_64_fastpath+0x12/0x6b
   [52174.561288] ---[ end trace 6b53049efb1a3ea6 ]---

Fix this by forcing a transaction commit when such cases happen.
This means we check in the commit root of the subvolume tree if there
was any other inode with the same reference when the inode we are
fsync'ing is a new inode (created in the current transaction).

Test cases for fstests, covering all the scenarios given above, were
submitted upstream for fstests:

  * fstests: generic test for fsync after renaming directory
    https://patchwork.kernel.org/patch/8694281/

  * fstests: generic test for fsync after renaming file
    https://patchwork.kernel.org/patch/8694301/

  * fstests: add btrfs test for fsync after snapshot deletion
    https://patchwork.kernel.org/patch/8670671/

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20 15:42:14 +09:00
Theodore Ts'o
ee8516a130 ext4: ignore quota mount options if the quota feature is enabled
commit c325a67c72903e1cc30e990a15ce745bda0dbfde upstream.

Previously, ext4 would fail the mount if the file system had the quota
feature enabled and quota mount options (used for the older quota
setups) were present.  This broke xfstests, since xfs silently ignores
the usrquote and grpquota mount options if they are specified.  This
commit changes things so that we are consistent with xfs; having the
mount options specified is harmless, so no sense break users by
forbidding them.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20 15:42:13 +09:00
Theodore Ts'o
321299a96e ext4: add lockdep annotations for i_data_sem
commit daf647d2dd58cec59570d7698a45b98e580f2076 upstream.

With the internal Quota feature, mke2fs creates empty quota inodes and
quota usage tracking is enabled as soon as the file system is mounted.
Since quotacheck is no longer preallocating all of the blocks in the
quota inode that are likely needed to be written to, we are now seeing
a lockdep false positive caused by needing to allocate a quota block
from inside ext4_map_blocks(), while holding i_data_sem for a data
inode.  This results in this complaint:

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(&ei->i_data_sem);
                                lock(&s->s_dquot.dqio_mutex);
                                lock(&ei->i_data_sem);
   lock(&s->s_dquot.dqio_mutex);

Google-Bug-Id: 27907753

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20 15:42:13 +09:00
Filipe Manana
df041ded89 btrfs: fix crash/invalid memory access on fsync when using overlayfs
commit de17e793b104d690e1d007dfc5cb6b4f649598ca upstream.

If the lower or upper directory of an overlayfs mount belong to a btrfs
file system and we fsync the file through the overlayfs' merged directory
we ended up accessing an inode that didn't belong to btrfs as if it were
a btrfs inode at btrfs_sync_file() resulting in a crash like the following:

[ 7782.588845] BUG: unable to handle kernel NULL pointer dereference at 0000000000000544
[ 7782.590624] IP: [<ffffffffa030b7ab>] btrfs_sync_file+0x11b/0x3e9 [btrfs]
[ 7782.591931] PGD 4d954067 PUD 1e878067 PMD 0
[ 7782.592016] Oops: 0002 [#6] PREEMPT SMP DEBUG_PAGEALLOC
[ 7782.592016] Modules linked in: btrfs overlay ppdev crc32c_generic evdev xor raid6_pq psmouse pcspkr sg serio_raw acpi_cpufreq parport_pc parport tpm_tis i2c_piix4 tpm i2c_core processor button loop autofs4 ext4 crc16 mbcache jbd2 sr_mod cdrom sd_mod ata_generic virtio_scsi ata_piix virtio_pci libata virtio_ring virtio scsi_mod e1000 floppy [last unloaded: btrfs]
[ 7782.592016] CPU: 10 PID: 16437 Comm: xfs_io Tainted: G      D         4.5.0-rc6-btrfs-next-26+ #1
[ 7782.592016] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
[ 7782.592016] task: ffff88001b8d40c0 ti: ffff880137488000 task.ti: ffff880137488000
[ 7782.592016] RIP: 0010:[<ffffffffa030b7ab>]  [<ffffffffa030b7ab>] btrfs_sync_file+0x11b/0x3e9 [btrfs]
[ 7782.592016] RSP: 0018:ffff88013748be40  EFLAGS: 00010286
[ 7782.592016] RAX: 0000000080000000 RBX: ffff880133b30c88 RCX: 0000000000000001
[ 7782.592016] RDX: 0000000000000001 RSI: ffffffff8148fec0 RDI: 00000000ffffffff
[ 7782.592016] RBP: ffff88013748bec0 R08: 0000000000000001 R09: 0000000000000000
[ 7782.624248] R10: ffff88013748be40 R11: 0000000000000246 R12: 0000000000000000
[ 7782.624248] R13: 0000000000000000 R14: 00000000009305a0 R15: ffff880015e3be40
[ 7782.624248] FS:  00007fa83b9cb700(0000) GS:ffff88023ed40000(0000) knlGS:0000000000000000
[ 7782.624248] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 7782.624248] CR2: 0000000000000544 CR3: 00000001fa652000 CR4: 00000000000006e0
[ 7782.624248] Stack:
[ 7782.624248]  ffffffff8108b5cc ffff88013748bec0 0000000000000246 ffff8800b005ded0
[ 7782.624248]  ffff880133b30d60 8000000000000000 7fffffffffffffff 0000000000000246
[ 7782.624248]  0000000000000246 ffffffff81074f9b ffffffff8104357c ffff880015e3be40
[ 7782.624248] Call Trace:
[ 7782.624248]  [<ffffffff8108b5cc>] ? arch_local_irq_save+0x9/0xc
[ 7782.624248]  [<ffffffff81074f9b>] ? ___might_sleep+0xce/0x217
[ 7782.624248]  [<ffffffff8104357c>] ? __do_page_fault+0x3c0/0x43a
[ 7782.624248]  [<ffffffff811a2351>] vfs_fsync_range+0x8c/0x9e
[ 7782.624248]  [<ffffffff811a237f>] vfs_fsync+0x1c/0x1e
[ 7782.624248]  [<ffffffff811a24d6>] do_fsync+0x31/0x4a
[ 7782.624248]  [<ffffffff811a2700>] SyS_fsync+0x10/0x14
[ 7782.624248]  [<ffffffff81493617>] entry_SYSCALL_64_fastpath+0x12/0x6b
[ 7782.624248] Code: 85 c0 0f 85 e2 02 00 00 48 8b 45 b0 31 f6 4c 29 e8 48 ff c0 48 89 45 a8 48 8d 83 d8 00 00 00 48 89 c7 48 89 45 a0 e8 fc 43 18 e1 <f0> 41 ff 84 24 44 05 00 00 48 8b 83 58 ff ff ff 48 c1 e8 07 83
[ 7782.624248] RIP  [<ffffffffa030b7ab>] btrfs_sync_file+0x11b/0x3e9 [btrfs]
[ 7782.624248]  RSP <ffff88013748be40>
[ 7782.624248] CR2: 0000000000000544
[ 7782.661994] ---[ end trace 721e14960eb939bc ]---

This started happening since commit 4bacc9c923 (overlayfs: Make f_path
always point to the overlay and f_inode to the underlay) and even though
after this change we could still access the btrfs inode through
struct file->f_mapping->host or struct file->f_inode, we would end up
resulting in more similar issues later on at check_parent_dirs_for_sync()
because the dentry we got (from struct file->f_path.dentry) was from
overlayfs and not from btrfs, that is, we had no way of getting the dentry
that belonged to btrfs (we always got the dentry that belonged to
overlayfs).

The new patch from Miklos Szeredi, titled "vfs: add file_dentry()" and
recently submitted to linux-fsdevel, adds a file_dentry() API that allows
us to get the btrfs dentry from the input file and therefore being able
to fsync when the upper and lower directories belong to btrfs filesystems.

This issue has been reported several times by users in the mailing list
and bugzilla. A test case for xfstests is being submitted as well.

Fixes: 4bacc9c923 ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=101951
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=109791
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20 15:42:13 +09:00
Miklos Szeredi
fda9797a6a nfs: use file_dentry()
commit be62a1a8fd116f5cd9e53726601f970e16e17558 upstream.

NFS may be used as lower layer of overlayfs and accessing f_path.dentry can
lead to a crash.

Fix by replacing direct access of file->f_path.dentry with the
file_dentry() accessor, which will always return a native object.

Fixes: 4bacc9c923 ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Tested-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Acked-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20 15:42:13 +09:00
Miklos Szeredi
c452dfc332 fs: add file_dentry()
commit d101a125954eae1d397adda94ca6319485a50493 upstream.

This series fixes bugs in nfs and ext4 due to 4bacc9c923 ("overlayfs:
Make f_path always point to the overlay and f_inode to the underlay").

Regular files opened on overlayfs will result in the file being opened on
the underlying filesystem, while f_path points to the overlayfs
mount/dentry.

This confuses filesystems which get the dentry from struct file and assume
it's theirs.

Add a new helper, file_dentry() [*], to get the filesystem's own dentry
from the file.  This checks file->f_path.dentry->d_flags against
DCACHE_OP_REAL, and returns file->f_path.dentry if DCACHE_OP_REAL is not
set (this is the common, non-overlayfs case).

In the uncommon case it will call into overlayfs's ->d_real() to get the
underlying dentry, matching file_inode(file).

The reason we need to check against the inode is that if the file is copied
up while being open, d_real() would return the upper dentry, while the open
file comes from the lower dentry.

[*] If possible, it's better simply to use file_inode() instead.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Tested-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Daniel Axtens <dja@axtens.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20 15:42:12 +09:00
Alex Shi
08562bfcb8 Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android 2016-04-13 12:02:21 +08:00
Joseph Qi
eae2b56828 ocfs2/dlm: fix BUG in dlm_move_lockres_to_recovery_list
commit be12b299a83fc807bbaccd2bcb8ec50cbb0cb55c upstream.

When master handles convert request, it queues ast first and then
returns status.  This may happen that the ast is sent before the request
status because the above two messages are sent by two threads.  And
right after the ast is sent, if master down, it may trigger BUG in
dlm_move_lockres_to_recovery_list in the requested node because ast
handler moves it to grant list without clear lock->convert_pending.  So
remove BUG_ON statement and check if the ast is processed in
dlmconvert_remote.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reported-by: Yiwen Jiang <jiangyiwen@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Tariq Saeed <tariq.x.saeed@oracle.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12 09:09:04 -07:00
Joseph Qi
e4b0e67342 ocfs2/dlm: fix race between convert and recovery
commit ac7cf246dfdbec3d8fed296c7bf30e16f5099dac upstream.

There is a race window between dlmconvert_remote and
dlm_move_lockres_to_recovery_list, which will cause a lock with
OCFS2_LOCK_BUSY in grant list, thus system hangs.

dlmconvert_remote
{
        spin_lock(&res->spinlock);
        list_move_tail(&lock->list, &res->converting);
        lock->convert_pending = 1;
        spin_unlock(&res->spinlock);

        status = dlm_send_remote_convert_request();
        >>>>>> race window, master has queued ast and return DLM_NORMAL,
               and then down before sending ast.
               this node detects master down and calls
               dlm_move_lockres_to_recovery_list, which will revert the
               lock to grant list.
               Then OCFS2_LOCK_BUSY won't be cleared as new master won't
               send ast any more because it thinks already be authorized.

        spin_lock(&res->spinlock);
        lock->convert_pending = 0;
        if (status != DLM_NORMAL)
                dlm_revert_pending_convert(res, lock);
        spin_unlock(&res->spinlock);
}

In this case, check if res->state has DLM_LOCK_RES_RECOVERING bit set
(res is still in recovering) or res master changed (new master has
finished recovery), reset the status to DLM_RECOVERING, then it will
retry convert.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reported-by: Yiwen Jiang <jiangyiwen@huawei.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Tariq Saeed <tariq.x.saeed@oracle.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12 09:09:04 -07:00
Tejun Heo
842ec116c7 writeback, cgroup: fix use of the wrong bdi_writeback which mismatches the inode
commit aaf2559332ba272671bb870464a99b909b29a3a1 upstream.

When cgroup writeback is in use, there can be multiple wb's
(bdi_writeback's) per bdi and an inode may switch among them
dynamically.  In a couple places, the wrong wb was used leading to
performing operations on the wrong list under the wrong lock
corrupting the io lists.

* writeback_single_inode() was taking @wb parameter and used it to
  remove the inode from io lists if it becomes clean after writeback.
  The callers of this function were always passing in the root wb
  regardless of the actual wb that the inode was associated with,
  which could also change while writeback is in progress.

  Fix it by dropping the @wb parameter and using
  inode_to_wb_and_lock_list() to determine and lock the associated wb.

* After writeback_sb_inodes() writes out an inode, it re-locks @wb and
  inode to remove it from or move it to the right io list.  It assumes
  that the inode is still associated with @wb; however, the inode may
  have switched to another wb while writeback was in progress.

  Fix it by using inode_to_wb_and_lock_list() to determine and lock
  the associated wb after writeback is complete.  As the function
  requires the original @wb->list_lock locked for the next iteration,
  in the unlikely case where the inode has changed association, switch
  the locks.

Kudos to Tahsin for pinpointing these subtle breakages.

Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: d10c809552 ("writeback: implement foreign cgroup inode bdi_writeback switching")
Link: http://lkml.kernel.org/g/CAAeU0aMYeM_39Y2+PaRvyB1nqAPYZSNngJ1eBRmrxn7gKAt2Mg@mail.gmail.com
Reported-and-diagnosed-by: Tahsin Erdogan <tahsin@google.com>
Tested-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12 09:09:04 -07:00
Tejun Heo
d78ddcfbe7 writeback, cgroup: fix premature wb_put() in locked_inode_to_wb_and_lock_list()
commit 614a4e3773148a31f58dc174bbf578ceb63510c2 upstream.

locked_inode_to_wb_and_lock_list() wb_get()'s the wb associated with
the target inode, unlocks inode, locks the wb's list_lock and verifies
that the inode is still associated with the wb.  To prevent the wb
going away between dropping inode lock and acquiring list_lock, the wb
is pinned while inode lock is held.  The wb reference is put right
after acquiring list_lock citing that the wb won't be dereferenced
anymore.

This isn't true.  If the inode is still associated with the wb, the
inode has reference and it's safe to return the wb; however, if inode
has been switched, the wb still needs to be unlocked which is a
dereference and can lead to use-after-free if it it races with wb
destruction.

Fix it by putting the reference after releasing list_lock.

Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: 87e1d789bf ("writeback: implement [locked_]inode_to_wb_and_lock_list()")
Tested-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12 09:09:04 -07:00
J. Bruce Fields
56fb92d684 nfsd: fix deadlock secinfo+readdir compound
commit 2f6fc056e899bd0144a08da5cacaecbe8997cd74 upstream.

nfsd_lookup_dentry exits with the parent filehandle locked.  fh_put also
unlocks if necessary (nfsd filehandle locking is probably too lenient),
so it gets unlocked eventually, but if the following op in the compound
needs to lock it again, we can deadlock.

A fuzzer ran into this; normal clients don't send a secinfo followed by
a readdir in the same compound.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12 09:09:03 -07:00
J. Bruce Fields
9ef1ecc409 nfsd4: fix bad bounds checking
commit 4aed9c46afb80164401143aa0fdcfe3798baa9d5 upstream.

A number of spots in the xdr decoding follow a pattern like

	n = be32_to_cpup(p++);
	READ_BUF(n + 4);

where n is a u32.  The only bounds checking is done in READ_BUF itself,
but since it's checking (n + 4), it won't catch cases where n is very
large, (u32)(-4) or higher.  I'm not sure exactly what the consequences
are, but we've seen crashes soon after.

Instead, just break these up into two READ_BUF()s.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12 09:09:03 -07:00
Jann Horn
74b23f79f1 fs/coredump: prevent fsuid=0 dumps into user-controlled directories
commit 378c6520e7d29280f400ef2ceaf155c86f05a71a upstream.

This commit fixes the following security hole affecting systems where
all of the following conditions are fulfilled:

 - The fs.suid_dumpable sysctl is set to 2.
 - The kernel.core_pattern sysctl's value starts with "/". (Systems
   where kernel.core_pattern starts with "|/" are not affected.)
 - Unprivileged user namespace creation is permitted. (This is
   true on Linux >=3.8, but some distributions disallow it by
   default using a distro patch.)

Under these conditions, if a program executes under secure exec rules,
causing it to run with the SUID_DUMP_ROOT flag, then unshares its user
namespace, changes its root directory and crashes, the coredump will be
written using fsuid=0 and a path derived from kernel.core_pattern - but
this path is interpreted relative to the root directory of the process,
allowing the attacker to control where a coredump will be written with
root privileges.

To fix the security issue, always interpret core_pattern for dumps that
are written under SUID_DUMP_ROOT relative to the root directory of init.

Signed-off-by: Jann Horn <jann@thejh.net>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12 09:08:58 -07:00
Seth Forshee
37bd8c883e fuse: Add reference counting for fuse_io_priv
commit 744742d692e37ad5c20630e57d526c8f2e2fe3c9 upstream.

The 'reqs' member of fuse_io_priv serves two purposes. First is to track
the number of oustanding async requests to the server and to signal that
the io request is completed. The second is to be a reference count on the
structure to know when it can be freed.

For sync io requests these purposes can be at odds.  fuse_direct_IO() wants
to block until the request is done, and since the signal is sent when
'reqs' reaches 0 it cannot keep a reference to the object. Yet it needs to
use the object after the userspace server has completed processing
requests. This leads to some handshaking and special casing that it
needlessly complicated and responsible for at least one race condition.

It's much cleaner and safer to maintain a separate reference count for the
object lifecycle and to let 'reqs' just be a count of outstanding requests
to the userspace server. Then we can know for sure when it is safe to free
the object without any handshaking or special cases.

The catch here is that most of the time these objects are stack allocated
and should not be freed. Initializing these objects with a single reference
that is never released prevents accidental attempts to free the objects.

Fixes: 9d5722b777 ("fuse: handle synchronous iocbs internally")
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12 09:08:58 -07:00
Robert Doebbelin
32b9807433 fuse: do not use iocb after it may have been freed
commit 7cabc61e01a0a8b663bd2b4c982aa53048218734 upstream.

There's a race in fuse_direct_IO(), whereby is_sync_kiocb() is called on an
iocb that could have been freed if async io has already completed.  The fix
in this case is simple and obvious: cache the result before starting io.

It was discovered by KASan:

kernel: ==================================================================
kernel: BUG: KASan: use after free in fuse_direct_IO+0xb1a/0xcc0 at addr ffff88036c414390

Signed-off-by: Robert Doebbelin <robert@quobyte.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: bcba24ccdc ("fuse: enable asynchronous processing direct IO")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12 09:08:58 -07:00
Mateusz Guzik
b34291f71d xfs: fix two memory leaks in xfs_attr_list.c error paths
commit 2e83b79b2d6c78bf1b4aa227938a214dcbddc83f upstream.

This plugs 2 trivial leaks in xfs_attr_shortform_list and
xfs_attr3_leaf_list_int.

Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12 09:08:56 -07:00
Nikolay Borisov
6b3ae95f03 quota: Fix possible GPF due to uninitialised pointers
commit ab73ef46398e2c0159f3a71de834586422d2a44a upstream.

When dqget() in __dquot_initialize() fails e.g. due to IO error,
__dquot_initialize() will pass an array of uninitialized pointers to
dqput_all() and thus can lead to deference of random data. Fix the
problem by properly initializing the array.

Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12 09:08:56 -07:00
Rabin Vincent
ab14444f6f splice: handle zero nr_pages in splice_to_pipe()
commit d6785d9152147596f60234157da2b02540c3e60f upstream.

Running the following command:

 busybox cat /sys/kernel/debug/tracing/trace_pipe > /dev/null

with any tracing enabled pretty very quickly leads to various NULL
pointer dereferences and VM BUG_ON()s, such as these:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
 IP: [<ffffffff8119df6c>] generic_pipe_buf_release+0xc/0x40
 Call Trace:
  [<ffffffff811c48a3>] splice_direct_to_actor+0x143/0x1e0
  [<ffffffff811c42e0>] ? generic_pipe_buf_nosteal+0x10/0x10
  [<ffffffff811c49cf>] do_splice_direct+0x8f/0xb0
  [<ffffffff81196869>] do_sendfile+0x199/0x380
  [<ffffffff81197600>] SyS_sendfile64+0x90/0xa0
  [<ffffffff8192cbee>] entry_SYSCALL_64_fastpath+0x12/0x6d

 page dumped because: VM_BUG_ON_PAGE(atomic_read(&page->_count) == 0)
 kernel BUG at include/linux/mm.h:367!
 invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
 RIP: [<ffffffff8119df9c>] generic_pipe_buf_release+0x3c/0x40
 Call Trace:
  [<ffffffff811c48a3>] splice_direct_to_actor+0x143/0x1e0
  [<ffffffff811c42e0>] ? generic_pipe_buf_nosteal+0x10/0x10
  [<ffffffff811c49cf>] do_splice_direct+0x8f/0xb0
  [<ffffffff81196869>] do_sendfile+0x199/0x380
  [<ffffffff81197600>] SyS_sendfile64+0x90/0xa0
  [<ffffffff8192cd1e>] tracesys_phase2+0x84/0x89

(busybox's cat uses sendfile(2), unlike the coreutils version)

This is because tracing_splice_read_pipe() can call splice_to_pipe()
with spd->nr_pages == 0.  spd_pages underflows in splice_to_pipe() and
we fill the page pointers and the other fields of the pipe_buffers with
garbage.

All other callers of splice_to_pipe() avoid calling it when nr_pages ==
0, and we could make tracing_splice_read_pipe() do that too, but it
seems reasonable to have splice_to_page() handle this condition
gracefully.

Signed-off-by: Rabin Vincent <rabin@rab.in>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12 09:08:55 -07:00
Dmitry V. Levin
994f9db391 vfs: show_vfsstat: do not ignore errors from show_devname method
commit 5f8d498d4364f544fee17125787a47553db02afa upstream.

Explicitly check show_devname method return code and bail out in case
of an error.  This fixes regression introduced by commit 9d4d65748a.

Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12 09:08:55 -07:00
OGAWA Hirofumi
93272beafa jbd2: fix FS corruption possibility in jbd2_journal_destroy() on umount path
commit c0a2ad9b50dd80eeccd73d9ff962234590d5ec93 upstream.

On umount path, jbd2_journal_destroy() writes latest transaction ID
(->j_tail_sequence) to be used at next mount.

The bug is that ->j_tail_sequence is not holding latest transaction ID
in some cases. So, at next mount, there is chance to conflict with
remaining (not overwritten yet) transactions.

	mount (id=10)
	write transaction (id=11)
	write transaction (id=12)
	umount (id=10) <= the bug doesn't write latest ID

	mount (id=10)
	write transaction (id=11)
	crash

	mount
	[recovery process]
		transaction (id=11)
		transaction (id=12) <= valid transaction ID, but old commit
                                       must not replay

Like above, this bug become the cause of recovery failure, or FS
corruption.

So why ->j_tail_sequence doesn't point latest ID?

Because if checkpoint transactions was reclaimed by memory pressure
(i.e. bdev_try_to_free_page()), then ->j_tail_sequence is not updated.
(And another case is, __jbd2_journal_clean_checkpoint_list() is called
with empty transaction.)

So in above cases, ->j_tail_sequence is not pointing latest
transaction ID at umount path. Plus, REQ_FLUSH for checkpoint is not
done too.

So, to fix this problem with minimum changes, this patch updates
->j_tail_sequence, and issue REQ_FLUSH.  (With more complex changes,
some optimizations would be possible to avoid unnecessary REQ_FLUSH
for example though.)

BTW,

	journal->j_tail_sequence =
		++journal->j_transaction_sequence;

Increment of ->j_transaction_sequence seems to be unnecessary, but
ext3 does this.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12 09:08:53 -07:00
Daniel Rosenberg
30e5f6e073 sdcardfs: remove unneeded __init and __exit
Change-Id: I2a2d45d52f891332174c3000e8681c5167c1564f
2016-04-07 16:50:04 +05:30
Daniel Rosenberg
c4fcf3f1c1 sdcardfs: Remove unused code
Change-Id: Ie97cba27ce44818ac56cfe40954f164ad44eccf6
2016-04-07 16:50:04 +05:30
Guenter Roeck
d023b7c5ee fs: Export d_absolute_path
The 0-day build bot reports the following build error, seen if SDCARD_FS
is built as module.

ERROR: "d_absolute_path" undefined!

Fixes: 84a1b7d3d3 ("Included sdcardfs source code for kernel 3.0")
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Guenter Roeck <groeck@chromium.org>
2016-04-07 16:50:03 +05:30
Daniel Rosenberg
1a98a1b1e6 sdcardfs: remove effectless config option
CONFIG_SDCARD_FS_CI_SEARCH only guards a define for
LOOKUP_CASE_INSENSITIVE, which is never used in the
kernel. Remove both, along with the option matching
that supports it.

Change-Id: I363a8f31de8ee7a7a934d75300cc9ba8176e2edf
Signed-off-by: Daniel Rosenberg <drosen@google.com>
2016-04-07 16:50:03 +05:30
Daniel Rosenberg
ce15174caf inotify: Fix erroneous update of bit count
Patch "vfs: add d_canonical_path for stacked filesystem support"
erroneously updated the ALL_INOTIFY_BITS count. This changes it back

Change-Id: Idb04edc736da276159d30f04c40cff9d6b1e070f
2016-04-07 16:50:03 +05:30
Daniel Rosenberg
815899d234 sdcardfs: Add support for d_canonical_path
Change-Id: I5d6f0e71b8ca99aec4b0894412f1dfd1cfe12add
Signed-off-by: Daniel Rosenberg <drosen@google.com>
2016-04-07 16:50:02 +05:30
Daniel Rosenberg
735236039d vfs: add d_canonical_path for stacked filesystem support
Inotify does not currently know when a filesystem
is acting as a wrapper around another fs. This means
that inotify watchers will miss any modifications to
the base file, as well as any made in a separate
stacked fs that points to the same file.
d_canonical_path solves this problem by allowing the fs
to map a dentry to a path in the lower fs. Inotify
can use it to find the appropriate place to watch to
be informed of all changes to a file.

Change-Id: I09563baffad1711a045e45c1bd0bd8713c2cc0b6
Signed-off-by: Daniel Rosenberg <drosen@google.com>
2016-04-07 16:50:02 +05:30
Daniel Rosenberg
b0f3f87bc1 sdcardfs: Bring up to date with Android M permissions:
In M, the workings of sdcardfs were changed significantly.
This brings sdcardfs into line with the changes.

Change-Id: I10e91a84a884c838feef7aa26c0a2b21f02e052e
2016-04-07 16:50:02 +05:30
Daniel Campello
ef5f9857ff Changed type-casting in packagelist management
Fixed existing type-casting in packagelist management code. All
warnings at compile time were taken care of.

Change-Id: I1ea97786d1d1325f31b9f09ae966af1f896a2af5
Signed-off-by: Daniel Campello <campello@google.com>
2016-04-07 16:50:02 +05:30
Daniel Campello
d2d6d73bc3 Port of sdcardfs to 4.4
Change-Id: I25b99ecf214e72ebf6a57ec3085972542a8d7951
Signed-off-by: Daniel Rosenberg <drosen@google.com>
2016-04-07 16:50:01 +05:30
Daniel Campello
c4190692cd Included sdcardfs source code for kernel 3.0
Only included the source code as is for kernel 3.0. Following patches
take care of porting this file system to version 3.10.

Change-Id: I09e76db77cd98a059053ba5b6fd88572a4b75b5b
Signed-off-by: Daniel Campello <campello@google.com>
2016-04-07 16:50:01 +05:30
dcashman
818ad76fe6 FROMLIST: mm: ASLR: use get_random_long()
(cherry picked from commit https://lkml.org/lkml/2016/2/4/833)

Replace calls to get_random_int() followed by a cast to (unsigned long)
with calls to get_random_long().  Also address shifting bug which, in case
of x86 removed entropy mask for mmap_rnd_bits values > 31 bits.

Bug: 26963541
Signed-off-by: Daniel Cashman <dcashman@android.com>
Signed-off-by: Daniel Cashman <dcashman@google.com>
Change-Id: I36c156c9b8d7d157134895fddd4cd6efddcbee86
2016-04-07 16:49:59 +05:30
Brian Norris
772d83a929 FROMLIST: pstore-ram: fix NULL reference when used with pdata
When using platform-data (not DT), we get an OOPS, because drvdata is
only initialized after we try to use it.

This addresses my comments made on the upstream submission here:

https://patchwork.kernel.org/patch/7980651/

Fixes boot on Chrome OS systems, including the Pixel 2.

Change-Id: I97360edf2ce61c83dc543cb6c169f3287e2dae4b
Fixes: b1d1b7187c ("FROMLIST: pstore-ram: add Device Tree bindings")
Signed-off-by: Brian Norris <briannorris@google.com>
2016-04-07 16:49:59 +05:30
Daniel Rosenberg
73fbdac211 sdcardfs: remove unneeded __init and __exit
Change-Id: I2a2d45d52f891332174c3000e8681c5167c1564f
2016-03-29 00:21:06 +00:00
Daniel Rosenberg
a5aa95121d sdcardfs: Remove unused code
Change-Id: Ie97cba27ce44818ac56cfe40954f164ad44eccf6
2016-03-29 00:20:52 +00:00
Gilad Broner
f50a4a1dc7 eCryptfs: fixed bug in cipher handling
Cipher was sometimes not treated properly, causing valid
requests belonging to eCryptfs to be treated as regular.

Change-Id: Iabfb93cc4c9e9e167901043482eb99613ed70343
Signed-off-by: Andrey Markovytch <andreym@codeaurora.org>
Signed-off-by: Gilad Broner <gbroner@codeaurora.org>
2016-03-25 16:04:06 -07:00
Guenter Roeck
cdaa7dcb05 fs: Export d_absolute_path
The 0-day build bot reports the following build error, seen if SDCARD_FS
is built as module.

ERROR: "d_absolute_path" undefined!

Fixes: 84a1b7d3d3 ("Included sdcardfs source code for kernel 3.0")
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Guenter Roeck <groeck@chromium.org>
2016-03-24 10:32:35 -07:00
Srivatsa Vaddagiri
3004236139 sched: colocate related threads
Provide userspace interface for tasks to be grouped together as
"related" threads. For example, all threads involved in updating
display buffer could be tagged as related.

Scheduler will attempt to provide special treatment for group of
related threads such as:

1) Colocation of related threads in same "preferred" cluster
2) Aggregation of demand towards determination of cluster frequency

This patch extends scheduler to provide best-effort colocation support
for a group of related threads.

Change-Id: Ic2cd769faf5da4d03a8f3cb0ada6224d0101a5f5
Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
[joonwoop@codeaurora.org: fixed minor merge conflicts.  removed ifdefry
 for CONFIG_SCHED_QHMP.]
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>

Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
2016-03-23 21:25:12 -07:00
Jeevan Shriram
643a137249 net: initialize variables to avoid UML compilation failure
While compiling for usermode linux for x86 architecture, observed
compilation issues with probable usage of uninitialized variables.
This change initializes the variables.

Signed-off-by: Jeevan Shriram <jshriram@codeaurora.org>
2016-03-23 21:24:21 -07:00
Andrey Markovytch
03bad71331 eCryptfs: fixes issue where files sometimes got corrupted upon close
Fixes implementation of cache cleaning, it was implemented using outdated
code which cleaned valid pages as well by mistake. The fix uses the
original implementation from mm layer which was tweaked to zero pages
after releasing them. Also it is now invoked only when there is HW
encryption (meaning that cache is unencrypted)

Change-Id: If713fd17a89be6d998c1a7ba86bee4c17d2bca0f
Signed-off-by: Andrey Markovytch <andreym@codeaurora.org>

Conflicts:
	fs/ecryptfs/caches_utils.c
2016-03-23 21:24:13 -07:00
Andrey Markovytch
b61ac21fb0 mm + fs: extends support for cache dropping
Exposes drop_pagecache_sb (required by eCryptfs cache wiping)
Adds truncate_inode_pages_fill_zero (required by eCryptfs cache wiping),
which not only truncates pages but also fills them with 0, so that the
cached data can no longer be retrieved.

Change-Id: Icfc18a2c8cdc922e71ee17add6459a1355e77ba6
Signed-off-by: Andrey Markovytch <andreym@codeaurora.org>
[gbroner@codeaurora.org: fix merge conflict]
Signed-off-by: Gilad Broner <gbroner@codeaurora.org>
2016-03-23 21:24:12 -07:00
Andrey Markovytch
36f1ad69fd eCryptfs: fixed some major bugs
1. Fixed bug which didn't allow several threads to work simultaneously
on files in eCryptfs mounted folder

2. Fixed bug where PFK close callback was invoked multiple times when
files was opened and closed multiple times. Now it is invoked just once
when files is closed for the last time

Change-Id: Iaa3ada03500e5a12752918b5d2bb4a852ddca5f0
Signed-off-by: Andrey Markovytch <andreym@codeaurora.org>
2016-03-23 21:24:11 -07:00
Andrey Markovytch
8928f8683b PFK: fixed issue where key in TZ was not set properly
When key is set in ICE via TZ, HLOS should send two parts, SALT and
the KEY itself according to AES standards. KEY was used for both parts.

Change-Id: I453dea289b01bdf49352d5209255966052f5dc1b
Signed-off-by: Andrey Markovytch <andreym@codeaurora.org>
2016-03-23 21:24:07 -07:00
Andrey Markovytch
5eebf86343 ecryptfs: enhancing ecryptfs to be configurable with encryption type
enabled eCryptfs for qcom targets. In addition to the usual
options, a special mode 'aes-xts' was added for qcom ICE hw
encryption

Change-Id: I20c01adc46c977b4a5db0be9ff93384cda14bc56
Signed-off-by: Lina Zarivach <linaz@codeaurora.org>
Signed-off-by: Andrey Markovytch <andreym@codeaurora.org>
[gbroner@codeaurora.org: fix merge conflict]
Signed-off-by: Gilad Broner <gbroner@codeaurora.org>
2016-03-23 21:24:05 -07:00
Andrey Markovytch
ecc052ba4e platform: msm: add Per-File-Tagger (PFT) driver
Integrated from msm-3.14. Additional fixes were made to compile with the
new kernel and various new warnings and checkpatch issues were fixed

Change-Id: I073db1041e41eac9066e37ee099f1da9e4eed6c0
Signed-off-by: Andrey Markovytch <andreym@codeaurora.org>
[gbroner@codeaurora.org: fixed merge conflict and adapted the LSM
security hooks]
Signed-off-by: Gilad Broner <gbroner@codeaurora.org>
2016-03-23 21:24:03 -07:00
Richard Weinberger
44cd578eeb ubifs: Use XATTR_*_PREFIX_LEN
...instead of open coding it.

CRs-Fixed: 975289
Change-Id: I2d2b2fecfd6724baddb1d93ec5b4aeb2587b577f
Signed-off-by: Richard Weinberger <richard@nod.at>
Git-commit: 4fdd1d51ad5d059548c6539ac9d281f74d24bcbe
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Nikhilesh Reddy <reddyn@codeaurora.org>
2016-03-23 21:20:20 -07:00