[PATCH] cifs: Use after free in debug code

[Dan Carpenter <error27@gmail.com>]

This debug code dereferences "old_iface" after it was already freed by
the call to release_iface().  Re-order the debugging to avoid this
issue.

Fixes: b54034a73baf ("cifs: during reconnect, update interface if necessary")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
 fs/cifs/sess.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index 92e4278ec35d..9e7d9f0baa18 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -302,14 +302,14 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
 
 	/* now drop the ref to the current iface */
 	if (old_iface && iface) {
-		kref_put(&old_iface->refcount, release_iface);
 		cifs_dbg(FYI, "replacing iface: %pIS with %pIS\n",
 			 &old_iface->sockaddr,
 			 &iface->sockaddr);
-	} else if (old_iface) {
 		kref_put(&old_iface->refcount, release_iface);
+	} else if (old_iface) {
 		cifs_dbg(FYI, "releasing ref to iface: %pIS\n",
 			 &old_iface->sockaddr);
+		kref_put(&old_iface->refcount, release_iface);
 	} else {
 		WARN_ON(!iface);
 		cifs_dbg(FYI, "adding new iface: %pIS\n", &iface->sockaddr);
-- 
2.35.1