diff options
author | Darrick J. Wong <darrick.wong@oracle.com> | 2016-01-04 16:13:21 +1100 |
---|---|---|
committer | Sasha Levin <sasha.levin@oracle.com> | 2016-06-03 19:15:17 -0400 |
commit | e8663801545a5e1059da85b5210a9a23939f3a82 (patch) | |
tree | 5cdab1fac3c9c4cf6a60fdef9e904dec9b69cf4c /fs/xfs | |
parent | 1fe949f6d0036130e1c62d2e5bee01d9b4ef0e51 (diff) |
libxfs: pack the agfl header structure so XFS_AGFL_SIZE is correct
[ Upstream commit 96f859d52bcb1c6ea6f3388d39862bf7143e2f30 ]
Because struct xfs_agfl is 36 bytes long and has a 64-bit integer
inside it, gcc will quietly round the structure size up to the nearest
64 bits -- in this case, 40 bytes. This results in the XFS_AGFL_SIZE
macro returning incorrect results for v5 filesystems on 64-bit
machines (118 items instead of 119). As a result, a 32-bit xfs_repair
will see garbage in AGFL item 119 and complain.
Therefore, tell gcc not to pad the structure so that the AGFL size
calculation is correct.
cc: <stable@vger.kernel.org> # 3.10 - 4.4
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Diffstat (limited to 'fs/xfs')
-rw-r--r-- | fs/xfs/libxfs/xfs_format.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h index 4daaa662337b..30c42ed58fc9 100644 --- a/fs/xfs/libxfs/xfs_format.h +++ b/fs/xfs/libxfs/xfs_format.h @@ -754,7 +754,7 @@ typedef struct xfs_agfl { __be64 agfl_lsn; __be32 agfl_crc; __be32 agfl_bno[]; /* actually XFS_AGFL_SIZE(mp) */ -} xfs_agfl_t; +} __attribute__((packed)) xfs_agfl_t; #define XFS_AGFL_CRC_OFF offsetof(struct xfs_agfl, agfl_crc) |