[MCAST]: Fix filter leak on device removal.

This fixes source filter leakage when a device is removed and a
process leaves the group thereafter.

This also includes corresponding fixes for IPv6 multicast source
filters on device removal.

Signed-off-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 4 deletions

diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 9d697d4dcff..639eb20c9f1 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -268,13 +268,14 @@ int ipv6_sock_mc_drop(struct sock *sk, int ifindex, struct in6_addr *addr)
                         if ((dev = dev_get_by_index(mc_lst->ifindex)) != NULL) {
                                 struct inet6_dev *idev = in6_dev_get(dev);
 
+                                (void) ip6_mc_leave_src(sk, mc_lst, idev);
                                 if (idev) {
-                                        (void) ip6_mc_leave_src(sk,mc_lst,idev);
                                         __ipv6_dev_mc_dec(idev, &mc_lst->addr);
                                         in6_dev_put(idev);
                                 }
                                 dev_put(dev);
-                        }
+                        } else
+                                (void) ip6_mc_leave_src(sk, mc_lst, NULL);
                         sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
                         return 0;
                 }
@@ -334,13 +335,14 @@ void ipv6_sock_mc_close(struct sock *sk)
                 if (dev) {
                         struct inet6_dev *idev = in6_dev_get(dev);
 
+                        (void) ip6_mc_leave_src(sk, mc_lst, idev);
                         if (idev) {
-                                (void) ip6_mc_leave_src(sk, mc_lst, idev);
                                 __ipv6_dev_mc_dec(idev, &mc_lst->addr);
                                 in6_dev_put(idev);
                         }
                         dev_put(dev);
-                }
+                } else
+                        (void) ip6_mc_leave_src(sk, mc_lst, NULL);
 
                 sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));