[PATCH V2] xfsprogs: fix use after free in inode_item_done()

[Eric Sandeen <sandeen@sandeen.net>]

Commit "3a19fb7 libxfs: stop caching inode structures"
introduced a use after free.

libxfs_iput() already does the check for ip->i_itemp, and a
kmem_zone_free() if it's present, and then frees the ip pointer.
Re-checking ip->i_itemp after the libxfs_iput call will access
the freed ip pointer, as will setting ip_>i_itemp to NULL.

Simply remove the offending code to fix this up.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
---

V2: Make it prettier based on Dave's comments.

diff --git a/libxfs/trans.c b/libxfs/trans.c
index 6c9d202..c443863 100644
--- a/libxfs/trans.c
+++ b/libxfs/trans.c
@@ -694,7 +694,6 @@ inode_item_done(
 	xfs_mount_t		*mp;
 	xfs_buf_t		*bp;
 	int			error;
-	extern kmem_zone_t	*xfs_ili_zone;
 
 	ip = iip->ili_inode;
 	mp = iip->ili_item.li_mountp;
@@ -736,15 +735,9 @@ ili_done:
 	if (iip->ili_lock_flags) {
 		iip->ili_lock_flags = 0;
 		return;
-	} else {
-		libxfs_iput(ip, 0);
 	}
-
-	if (ip->i_itemp)
-		kmem_zone_free(xfs_ili_zone, ip->i_itemp);
-	else
-		ASSERT(0);
-	ip->i_itemp = NULL;
+	/* free the inode */
+	libxfs_iput(ip, 0);
 }
 
 static void

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs