The patch below does not apply to the 3.13-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.
thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From b7d961b35b3ab69609aeea93f870269cb6e7ba4d Mon Sep 17 00:00:00 2001 From: Dave Chinner <[email protected]> Date: Thu, 21 Nov 2013 15:41:06 +1100 Subject: [PATCH] xfs: growfs overruns AGFL buffer on V4 filesystems 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. Cc: <[email protected]> Signed-off-by: Dave Chinner <[email protected]> Reviewed-by: Jie Liu <[email protected]> Signed-off-by: Ben Myers <[email protected]> diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c index a6e54b3319bd..02fb943cbf22 100644 --- a/fs/xfs/xfs_fsops.c +++ b/fs/xfs/xfs_fsops.c @@ -220,6 +220,8 @@ xfs_growfs_data_private( */ nfree = 0; for (agno = nagcount - 1; agno >= oagcount; agno--, new -= agsize) { + __be32 *agfl_bno; + /* * AG freespace header block */ @@ -279,8 +281,10 @@ 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); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
