2 files changed, 52 insertions, 14 deletions

diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 5cd99271d3a6..5171709199f4 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -536,12 +536,25 @@ out:
  *      Socket option code for IP. This is the end of the line after any
  *      TCP,UDP etc options on an IP socket.
  */
+static bool setsockopt_needs_rtnl(int optname)
+{
+        switch (optname) {
+        case IP_ADD_MEMBERSHIP:
+        case IP_ADD_SOURCE_MEMBERSHIP:
+        case IP_DROP_MEMBERSHIP:
+        case MCAST_JOIN_GROUP:
+        case MCAST_LEAVE_GROUP:
+                return true;
+        }
+        return false;
+}
 
 static int do_ip_setsockopt(struct sock *sk, int level,
                             int optname, char __user *optval, unsigned int optlen)
 {
         struct inet_sock *inet = inet_sk(sk);
         int val = 0, err;
+        bool needs_rtnl = setsockopt_needs_rtnl(optname);
 
         switch (optname) {
         case IP_PKTINFO:
@@ -584,6 +597,8 @@ static int do_ip_setsockopt(struct sock *sk, int level,
                 return ip_mroute_setsockopt(sk, optname, optval, optlen);
 
         err = 0;
+        if (needs_rtnl)
+                rtnl_lock();
         lock_sock(sk);
 
         switch (optname) {
@@ -846,9 +861,9 @@ static int do_ip_setsockopt(struct sock *sk, int level,
                 }
 
                 if (optname == IP_ADD_MEMBERSHIP)
-                        err = ip_mc_join_group(sk, &mreq);
+                        err = __ip_mc_join_group(sk, &mreq);
                 else
-                        err = ip_mc_leave_group(sk, &mreq);
+                        err = __ip_mc_leave_group(sk, &mreq);
                 break;
         }
         case IP_MSFILTER:
@@ -913,7 +928,7 @@ static int do_ip_setsockopt(struct sock *sk, int level,
                         mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
                         mreq.imr_address.s_addr = mreqs.imr_interface;
                         mreq.imr_ifindex = 0;
-                        err = ip_mc_join_group(sk, &mreq);
+                        err = __ip_mc_join_group(sk, &mreq);
                         if (err && err != -EADDRINUSE)
                                 break;
                         omode = MCAST_INCLUDE;
@@ -945,9 +960,9 @@ static int do_ip_setsockopt(struct sock *sk, int level,
                 mreq.imr_ifindex = greq.gr_interface;
 
                 if (optname == MCAST_JOIN_GROUP)
-                        err = ip_mc_join_group(sk, &mreq);
+                        err = __ip_mc_join_group(sk, &mreq);
                 else
-                        err = ip_mc_leave_group(sk, &mreq);
+                        err = __ip_mc_leave_group(sk, &mreq);
                 break;
         }
         case MCAST_JOIN_SOURCE_GROUP:
@@ -990,7 +1005,7 @@ static int do_ip_setsockopt(struct sock *sk, int level,
                         mreq.imr_multiaddr = psin->sin_addr;
                         mreq.imr_address.s_addr = 0;
                         mreq.imr_ifindex = greqs.gsr_interface;
-                        err = ip_mc_join_group(sk, &mreq);
+                        err = __ip_mc_join_group(sk, &mreq);
                         if (err && err != -EADDRINUSE)
                                 break;
                         greqs.gsr_interface = mreq.imr_ifindex;
@@ -1118,10 +1133,14 @@ mc_msf_out:
                 break;
         }
         release_sock(sk);
+        if (needs_rtnl)
+                rtnl_unlock();
         return err;
 
 e_inval:
         release_sock(sk);
+        if (needs_rtnl)
+                rtnl_unlock();
         return -EINVAL;
 }
 
diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index 8d766d9100cb..f2b731df8d77 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -117,6 +117,18 @@ struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
         return opt;
 }
 
+static bool setsockopt_needs_rtnl(int optname)
+{
+        switch (optname) {
+        case IPV6_ADD_MEMBERSHIP:
+        case IPV6_DROP_MEMBERSHIP:
+        case MCAST_JOIN_GROUP:
+        case MCAST_LEAVE_GROUP:
+                return true;
+        }
+        return false;
+}
+
 static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
                     char __user *optval, unsigned int optlen)
 {
@@ -124,6 +136,7 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
         struct net *net = sock_net(sk);
         int val, valbool;
         int retv = -ENOPROTOOPT;
+        bool needs_rtnl = setsockopt_needs_rtnl(optname);
 
         if (optval == NULL)
                 val = 0;
@@ -140,6 +153,8 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
         if (ip6_mroute_opt(optname))
                 return ip6_mroute_setsockopt(sk, optname, optval, optlen);
 
+        if (needs_rtnl)
+                rtnl_lock();
         lock_sock(sk);
 
         switch (optname) {
@@ -582,9 +597,9 @@ done:
                         break;
 
                 if (optname == IPV6_ADD_MEMBERSHIP)
-                        retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
+                        retv = __ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
                 else
-                        retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
+                        retv = __ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
                 break;
         }
         case IPV6_JOIN_ANYCAST:
@@ -623,11 +638,11 @@ done:
                 }
                 psin6 = (struct sockaddr_in6 *)&greq.gr_group;
                 if (optname == MCAST_JOIN_GROUP)
-                        retv = ipv6_sock_mc_join(sk, greq.gr_interface,
-                                &psin6->sin6_addr);
+                        retv = __ipv6_sock_mc_join(sk, greq.gr_interface,
+                                                   &psin6->sin6_addr);
                 else
-                        retv = ipv6_sock_mc_drop(sk, greq.gr_interface,
-                                &psin6->sin6_addr);
+                        retv = __ipv6_sock_mc_drop(sk, greq.gr_interface,
+                                                   &psin6->sin6_addr);
                 break;
         }
         case MCAST_JOIN_SOURCE_GROUP:
@@ -659,8 +674,8 @@ done:
                         struct sockaddr_in6 *psin6;
 
                         psin6 = (struct sockaddr_in6 *)&greqs.gsr_group;
-                        retv = ipv6_sock_mc_join(sk, greqs.gsr_interface,
-                                &psin6->sin6_addr);
+                        retv = __ipv6_sock_mc_join(sk, greqs.gsr_interface,
+                                                   &psin6->sin6_addr);
                         /* prior join w/ different source is ok */
                         if (retv && retv != -EADDRINUSE)
                                 break;
@@ -837,11 +852,15 @@ pref_skip_coa:
         }
 
         release_sock(sk);
+        if (needs_rtnl)
+                rtnl_unlock();
 
         return retv;
 
 e_inval:
         release_sock(sk);
+        if (needs_rtnl)
+                rtnl_unlock();
         return -EINVAL;
 }