diff options
author | Dave Chinner <dchinner@redhat.com> | 2013-11-21 15:41:06 +1100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-12-20 07:48:53 -0800 |
commit | 7b115360756c00867dfeb633daaf092c0a3996ba (patch) | |
tree | bd300f0d678983608753603c859b8e08756df75b /fs | |
parent | 51f3ae937ca288978ab3c63ec2ae48d687cb3347 (diff) |
xfs: growfs overruns AGFL buffer on V4 filesystems
commit f94c44573e7c22860e2c3dfe349c45f72ba35ad3 upstream.
This loop in xfs_growfs_data_private() is incorrect for V4
superblocks filesystems:
for (bucket = 0; bucket < XFS_AGFL_SIZE(mp); bucket++)
agfl->agfl_bno[bucket] = cpu_to_be32(NULLAGBLOCK);
For V4 filesystems, we don't have a agfl header structure, and so
XFS_AGFL_SIZE() returns an entire sector's worth of entries, which
we then index from an offset into the sector. Hence: buffer overrun.
This problem was introduced in 3.10 by commit 77c95bba ("xfs: add
CRC checks to the AGFL") which changed the AGFL structure but failed
to update the growfs code to handle the different structures.
Fix it by using the correct offset into the buffer for both V4 and
V5 filesystems.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/xfs/xfs_fsops.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c index e64ee5288b8..c888040a1e9 100644 --- a/fs/xfs/xfs_fsops.c +++ b/fs/xfs/xfs_fsops.c @@ -217,6 +217,8 @@ xfs_growfs_data_private( */ nfree = 0; for (agno = nagcount - 1; agno >= oagcount; agno--, new -= agsize) { + __be32 *agfl_bno; + /* * AG freespace header block */ @@ -276,8 +278,10 @@ xfs_growfs_data_private( agfl->agfl_seqno = cpu_to_be32(agno); uuid_copy(&agfl->agfl_uuid, &mp->m_sb.sb_uuid); } + + agfl_bno = XFS_BUF_TO_AGFL_BNO(mp, bp); for (bucket = 0; bucket < XFS_AGFL_SIZE(mp); bucket++) - agfl->agfl_bno[bucket] = cpu_to_be32(NULLAGBLOCK); + agfl_bno[bucket] = cpu_to_be32(NULLAGBLOCK); error = xfs_bwrite(bp); xfs_buf_relse(bp); |