[PATCH] xfs: fix xfs_log_ticket leak in xfs_end_io() after fs shutdown

[Brian Foster]

If the filesystem has shut down, xfs_end_io() currently sets an error on
the ioend and proceeds to ioend destruction. The ioend might contain a
truncate transaction if the I/O extended the size of the file. This
transaction is only cleaned up in xfs_setfilesize_ioend(), however,
which is skipped in this case. This results in an xfs_log_ticket leak
message when the associate cache slab is destroyed (e.g., on rmmod).

This was originally reproduced by xfs/141 on a distro kernel. The
problem is reproducible on an upstream kernel, but not easily detected
in current upstream if the xfs_log_ticket cache happens to be merged
with another cache. This can be reproduced more deterministically with
the 'slab_nomerge' kernel boot option.

Update xfs_end_io() to proceed with normal end I/O processing after an
error is set on an ioend due to fs shutdown. The I/O type-based
processing is already designed to handle an I/O error and ensure that
the ioend is cleaned up correctly.

Signed-off-by: Brian Foster <bfoster at redhat.com>
---
 fs/xfs/xfs_aops.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index 379c089..7bf8512 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -214,10 +214,12 @@ xfs_end_io(
 	struct xfs_inode *ip = XFS_I(ioend->io_inode);
 	int		error = 0;
 
-	if (XFS_FORCED_SHUTDOWN(ip->i_mount)) {
+	/*
+	 * Set an error if the mount has shut down and proceed with end I/O
+	 * processing so it can perform whatever cleanups are necessary.
+	 */
+	if (XFS_FORCED_SHUTDOWN(ip->i_mount))
 		ioend->io_error = -EIO;
-		goto done;
-	}
 
 	/*
 	 * For unwritten extents we need to issue transactions to convert a
-- 
2.4.3