cifs: Use after free in debug code

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: b54034a73b ("cifs: during reconnect, update interface if necessary")
Cc: stable@vger.kernel.org # 5.19+
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Dan Carpenter 2022-11-18 14:48:00 +03:00 committed by Steve French
parent 926028aaa3
commit f391d6ee00

View file

@ -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);