Commit 51b07f30 authored May 18, 2016 by Dave Chinner Committed by Dave Chinner May 18, 2016

xfs: fix inode validity check in xfs_iflush_cluster



Some careless idiot(*) wrote crap code in commit 1a3e8f3d ("xfs:
convert inode cache lookups to use RCU locking") back in late 2010,
and so xfs_iflush_cluster checks the wrong inode for whether it is
still valid under RCU protection. Fix it to lock and check the
correct inode.

(*) Careless-idiot: Dave Chinner <dchinner@redhat.com>

cc: <stable@vger.kernel.org> # 3.10.x-
Discovered-by: Brain Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>

parent b1438f47

fs/xfs/xfs_inode.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -3205,13 +3205,13 @@ xfs_iflush_cluster(
		* We need to check under the i_flags_lock for a valid inode
		* here. Skip it if it is not valid or the wrong inode.
		*/
		spin_lock(&ip->i_flags_lock);
		if (!ip->i_ino \|\|
		spin_lock(&iq->i_flags_lock);
		if (!iq->i_ino \|\|
		(XFS_INO_TO_AGINO(mp, iq->i_ino) & mask) != first_index) {
		spin_unlock(&ip->i_flags_lock);
		spin_unlock(&iq->i_flags_lock);
		continue;
		}
		spin_unlock(&ip->i_flags_lock);
		spin_unlock(&iq->i_flags_lock);

		/*
		* Do an un-protected check to see if the inode is dirty and