[Precise][CVE-2012-5374, CVE-2012-5375 0/1] Btrfs: fix hash overflow handling

[Luis Henriques]

Following this email, there's a backport to the Precise kernel of
commit:

  9c52057 Btrfs: fix hash overflow handling

This commit fixes 2 CVEs: CVE-2012-5374 and CVE-2012-5375.

This backport drops two changes from the original commit:

 * function btrfs_add_link, in fs/btrfs/inode.c
   In Precise, after calling btrfs_insert_dir_item(), there's a
   'BUG_ON(ret)', which already covers the EOVERFLOW case

 * function create_pending_snapshot, in fs/btrfs/transaction.c
   Same thing here: there's a 'BUG_ON(ret)' after calling
   btrfs_insert_dir_item() which also covers EOVERFLOW

There are also some minor context adjustments and, in function
btrfs_mksubvol (fs/btrfs/ioctl.c), a label in a 'goto' statement that had
to be modified.

This backport has been tested using the xfstests and no regressions
were found (although I don't think these tests would uncover the hash
overflow scenario).

Chris Mason (1):
  Btrfs: fix hash overflow handling

 fs/btrfs/ctree.h    |  2 ++
 fs/btrfs/dir-item.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/inode.c    | 22 ++++++++++++++++++++
 fs/btrfs/ioctl.c    | 10 +++++++++
 4 files changed, 93 insertions(+)

-- 
1.8.3.2