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

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: 53dd9a68ba68 ("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
index a11d3d89f0120a17c26f41a0559b6c40ebbbc6ca..a35f597e8c8bf4f15ad0f01aff29849d2bebe36f 100644 (file)
--- a/net/batman-adv/multicast.c
+++ b/net/batman-adv/multicast.c
@@ -1536,7 +1536,7 @@ out:
 
        if (!ret && primary_if)
                *primary_if = hard_iface;
-       else
+       else if (hard_iface)
                batadv_hardif_put(hard_iface);
 
        return ret;