batman-adv: don't pass a NULL hard_iface to batadv_hardif_put

Colin Ian King · simonwunderlich · commit 65cc02a8e1d4 · 2018-04-22T09:29:01.000+02:00
In the case where hard_iface is NULL, the error path may pass a null pointer to batadv_hardif_put causing a null pointer dereference error. Avoid this by only calling the function if hard_iface not null. Detected by CoverityScan, CID#1466456 ("Explicit null dereferenced") Fixes: 53dd9a6 ("batman-adv: add multicast flags netlink support") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c
@@ -1536,7 +1536,7 @@ batadv_mcast_netlink_get_primary(struct netlink_callback *cb,
 
 	if (!ret && primary_if)
 		*primary_if = hard_iface;
-	else
+	else if (hard_iface)
 		batadv_hardif_put(hard_iface);
 
 	return ret;
