[XFS] Fix use after free in xfs_log_done().

The ticket allocation code got reworked in 2.6.26 and we now free tickets
whereas before we used to cache them so the use-after-free went
undetected.

SGI-PV: 985525

SGI-Modid: xfs-linux-melb:xfs-kern:31877a

Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 1f6f780..ccba14e 100644 (file)
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -336,15 +336,12 @@ xfs_log_done(xfs_mount_t  *mp,
        } else {
                xlog_trace_loggrant(log, ticket, "xfs_log_done: (permanent)");
                xlog_regrant_reserve_log_space(log, ticket);
-       }
-
-       /* If this ticket was a permanent reservation and we aren't
-        * trying to release it, reset the inited flags; so next time
-        * we write, a start record will be written out.
-        */
-       if ((ticket->t_flags & XLOG_TIC_PERM_RESERV) &&
-           (flags & XFS_LOG_REL_PERM_RESERV) == 0)
+               /* If this ticket was a permanent reservation and we aren't
+                * trying to release it, reset the inited flags; so next time
+                * we write, a start record will be written out.
+                */
                ticket->t_flags |= XLOG_TIC_INITED;
+       }
 
        return lsn;
 }      /* xfs_log_done */