ipv4, ipv6: kill ip_mc_{join, leave}_group and ipv6_sock_mc_{join, drop}

in favor of their inner __ ones, which doesn't grab rtnl.

As these functions need to operate on a locked socket, we can't be
grabbing rtnl by then. It's too late and doing so causes reversed
locking.

So this patch:
- move rtnl handling to callers instead while already fixing some
  reversed locking situations, like on vxlan and ipvs code.
- renames __ ones to not have the __ mark:
  __ip_mc_{join,leave}_group -> ip_mc_{join,leave}_group
  __ipv6_sock_mc_{join,drop} -> ipv6_sock_mc_{join,drop}

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 18 insertions, 37 deletions

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 88d2cf0cae52..158378e73f0a 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -2473,9 +2473,9 @@ static int ipv6_mc_config(struct sock *sk, bool join,
 
 	lock_sock(sk);
 	if (join)
-		ret = __ipv6_sock_mc_join(sk, ifindex, addr);
+		ret = ipv6_sock_mc_join(sk, ifindex, addr);
 	else
-		ret = __ipv6_sock_mc_drop(sk, ifindex, addr);
+		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
 	release_sock(sk);
 
 	return ret;
diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index f2b731df8d77..cc5883791bac 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -124,6 +124,11 @@ static bool setsockopt_needs_rtnl(int optname)
 	case IPV6_DROP_MEMBERSHIP:
 	case MCAST_JOIN_GROUP:
 	case MCAST_LEAVE_GROUP:
+	case MCAST_JOIN_SOURCE_GROUP:
+	case MCAST_LEAVE_SOURCE_GROUP:
+	case MCAST_BLOCK_SOURCE:
+	case MCAST_UNBLOCK_SOURCE:
+	case MCAST_MSFILTER:
 		return true;
 	}
 	return false;
@@ -597,9 +602,9 @@ 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:
@@ -638,11 +643,11 @@ 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:
@@ -674,8 +679,8 @@ 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;
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 1dd1fedff9f4..cbb66fd3da6d 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -132,7 +132,7 @@ static int unsolicited_report_interval(struct inet6_dev *idev)
 	return iv > 0 ? iv : 1;
 }
 
-int __ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
+int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
 {
 	struct net_device *dev = NULL;
 	struct ipv6_mc_socklist *mc_lst;
@@ -199,24 +199,12 @@ int __ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *add
 
 	return 0;
 }
-EXPORT_SYMBOL(__ipv6_sock_mc_join);
-
-int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
-{
-	int ret;
-
-	rtnl_lock();
-	ret = __ipv6_sock_mc_join(sk, ifindex, addr);
-	rtnl_unlock();
-
-	return ret;
-}
 EXPORT_SYMBOL(ipv6_sock_mc_join);
 
 /*
  *	socket leave on multicast group
  */
-int __ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr)
+int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr)
 {
 	struct ipv6_pinfo *np = inet6_sk(sk);
 	struct ipv6_mc_socklist *mc_lst;
@@ -255,18 +243,6 @@ int __ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *add
 
 	return -EADDRNOTAVAIL;
 }
-EXPORT_SYMBOL(__ipv6_sock_mc_drop);
-
-int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr)
-{
-	int ret;
-
-	rtnl_lock();
-	ret = __ipv6_sock_mc_drop(sk, ifindex, addr);
-	rtnl_unlock();
-
-	return ret;
-}
 EXPORT_SYMBOL(ipv6_sock_mc_drop);
 
 /* called with rcu_read_lock() */
@@ -460,7 +436,7 @@ done:
 	read_unlock_bh(&idev->lock);
 	rcu_read_unlock();
 	if (leavegroup)
-		return ipv6_sock_mc_drop(sk, pgsr->gsr_interface, group);
+		err = ipv6_sock_mc_drop(sk, pgsr->gsr_interface, group);
 	return err;
 }