1 files changed, 8 insertions, 5 deletions

diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index 532425db11fe..1334fc174bcf 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -539,12 +539,15 @@ done:
         case IPV6_MULTICAST_IF:
                 if (sk->sk_type == SOCK_STREAM)
                         goto e_inval;
-                if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != val)
-                        goto e_inval;
 
-                if (__dev_get_by_index(&init_net, val) == NULL) {
-                        retv = -ENODEV;
-                        break;
+                if (val) {
+                        if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != val)
+                                goto e_inval;
+
+                        if (__dev_get_by_index(&init_net, val) == NULL) {
+                                retv = -ENODEV;
+                                break;
+                        }
                 }
                 np->mcast_oif = val;
                 retv = 0;