[3.19.y-ckt stable] Patch "libxfs: readahead of dir3 data blocks should use the read verifier" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    libxfs: readahead of dir3 data blocks should use the read verifier

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.8-ckt8.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 10faa3bae0fbfe7742c6e2d8ab8a1de408a9469a Mon Sep 17 00:00:00 2001
From: "Darrick J. Wong" <darrick.wong at oracle.com>
Date: Wed, 19 Aug 2015 10:33:58 +1000
Subject: libxfs: readahead of dir3 data blocks should use the read verifier

commit 2f123bce18943fff819bc10f8868ffb9149fc622 upstream.

In the dir3 data block readahead function, use the regular read
verifier to check the block's CRC and spot-check the block contents
instead of directly calling only the spot-checking routine.  This
prevents corrupted directory data blocks from being read into the
kernel, which can lead to garbage ls output and directory loops (if
say one of the entries contains slashes and other junk).

Signed-off-by: Darrick J. Wong <darrick.wong at oracle.com>
Reviewed-by: Dave Chinner <dchinner at redhat.com>
Signed-off-by: Dave Chinner <david at fromorbit.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 fs/xfs/libxfs/xfs_dir2_data.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/libxfs/xfs_dir2_data.c b/fs/xfs/libxfs/xfs_dir2_data.c
index 5ff31be..0bd0ca0 100644
--- a/fs/xfs/libxfs/xfs_dir2_data.c
+++ b/fs/xfs/libxfs/xfs_dir2_data.c
@@ -251,7 +251,8 @@ xfs_dir3_data_reada_verify(
 		return;
 	case cpu_to_be32(XFS_DIR2_DATA_MAGIC):
 	case cpu_to_be32(XFS_DIR3_DATA_MAGIC):
-		xfs_dir3_data_verify(bp);
+		bp->b_ops = &xfs_dir3_data_buf_ops;
+		bp->b_ops->verify_read(bp);
 		return;
 	default:
 		xfs_buf_ioerror(bp, -EFSCORRUPTED);
--
1.9.1