[PATCH 4.9 196/206] xfs: error out if trying to add attrs and anextents > 0

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------


From: "Darrick J. Wong" <darrick.wong@xxxxxxxxxx>

commit 0f352f8ee8412bd9d34fb2a6411241da61175c0e upstream.

We shouldn't assert if somehow we end up trying to add an attr fork to
an inode that apparently already has attr extents because this is an
indication of on-disk corruption.  Instead, return an error code to
userspace.

Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Reviewed-by: Dave Chinner <dchinner@xxxxxxxxxx>
Signed-off-by: Dave Chinner <david@xxxxxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 fs/xfs/libxfs/xfs_bmap.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -1153,6 +1153,10 @@ xfs_bmap_add_attrfork(
 		goto trans_cancel;
 	if (XFS_IFORK_Q(ip))
 		goto trans_cancel;
+	if (ip->i_d.di_anextents != 0) {
+		error = -EFSCORRUPTED;
+		goto trans_cancel;
+	}
 	if (ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS) {
 		/*
 		 * For inodes coming from pre-6.2 filesystems.
@@ -1160,7 +1164,6 @@ xfs_bmap_add_attrfork(
 		ASSERT(ip->i_d.di_aformat == 0);
 		ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
 	}
-	ASSERT(ip->i_d.di_anextents == 0);
 
 	xfs_trans_ijoin(tp, ip, 0);
 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);