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, 25 insertions, 41 deletions

diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index 375dc71b9a64..975ee5e30c64 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -560,9 +560,9 @@ static int ip_mc_config(struct sock *sk, bool join, const struct in_ifaddr *ifa)
 
         lock_sock(sk);
         if (join)
-                ret = __ip_mc_join_group(sk, &mreq);
+                ret = ip_mc_join_group(sk, &mreq);
         else
-                ret = __ip_mc_leave_group(sk, &mreq);
+                ret = ip_mc_leave_group(sk, &mreq);
         release_sock(sk);
 
         return ret;
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index 5cb1ef4ce292..ad3f866085de 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -1850,7 +1850,10 @@ static void ip_mc_clear_src(struct ip_mc_list *pmc)
         pmc->sfcount[MCAST_EXCLUDE] = 1;
 }
 
-int __ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
+/* Join a multicast group
+ */
+
+int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
 {
         __be32 addr = imr->imr_multiaddr.s_addr;
         struct ip_mc_socklist *iml, *i;
@@ -1898,20 +1901,6 @@ int __ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
 done:
         return err;
 }
-EXPORT_SYMBOL(__ip_mc_join_group);
-
-/* Join a multicast group
- */
-int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr)
-{
-        int ret;
-
-        rtnl_lock();
-        ret = __ip_mc_join_group(sk, imr);
-        rtnl_unlock();
-
-        return ret;
-}
 EXPORT_SYMBOL(ip_mc_join_group);
 
 static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
@@ -1934,7 +1923,7 @@ static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
         return err;
 }
 
-int __ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
+int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
 {
         struct inet_sock *inet = inet_sk(sk);
         struct ip_mc_socklist *iml;
@@ -1979,18 +1968,6 @@ int __ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
 out:
         return ret;
 }
-EXPORT_SYMBOL(__ip_mc_leave_group);
-
-int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr)
-{
-        int ret;
-
-        rtnl_lock();
-        ret = __ip_mc_leave_group(sk, imr);
-        rtnl_unlock();
-
-        return ret;
-}
 EXPORT_SYMBOL(ip_mc_leave_group);
 
 int ip_mc_source(int add, int omode, struct sock *sk, struct
@@ -2010,7 +1987,7 @@ int ip_mc_source(int add, int omode, struct sock *sk, struct
         if (!ipv4_is_multicast(addr))
                 return -EINVAL;
 
-        rtnl_lock();
+        ASSERT_RTNL();
 
         imr.imr_multiaddr.s_addr = mreqs->imr_multiaddr;
         imr.imr_address.s_addr = mreqs->imr_interface;
@@ -2124,9 +2101,8 @@ int ip_mc_source(int add, int omode, struct sock *sk, struct
         ip_mc_add_src(in_dev, &mreqs->imr_multiaddr, omode, 1,
                 &mreqs->imr_sourceaddr, 1);
 done:
-        rtnl_unlock();
         if (leavegroup)
-                return ip_mc_leave_group(sk, &imr);
+                err = ip_mc_leave_group(sk, &imr);
         return err;
 }
 
@@ -2148,7 +2124,7 @@ int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
             msf->imsf_fmode != MCAST_EXCLUDE)
                 return -EINVAL;
 
-        rtnl_lock();
+        ASSERT_RTNL();
 
         imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
         imr.imr_address.s_addr = msf->imsf_interface;
@@ -2210,7 +2186,6 @@ int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
         pmc->sfmode = msf->imsf_fmode;
         err = 0;
 done:
-        rtnl_unlock();
         if (leavegroup)
                 err = ip_mc_leave_group(sk, &imr);
         return err;
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 5171709199f4..f6a0d54b308a 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -541,9 +541,18 @@ static bool setsockopt_needs_rtnl(int optname)
         switch (optname) {
         case IP_ADD_MEMBERSHIP:
         case IP_ADD_SOURCE_MEMBERSHIP:
+        case IP_BLOCK_SOURCE:
         case IP_DROP_MEMBERSHIP:
+        case IP_DROP_SOURCE_MEMBERSHIP:
+        case IP_MSFILTER:
+        case IP_UNBLOCK_SOURCE:
+        case MCAST_BLOCK_SOURCE:
+        case MCAST_MSFILTER:
         case MCAST_JOIN_GROUP:
+        case MCAST_JOIN_SOURCE_GROUP:
         case MCAST_LEAVE_GROUP:
+        case MCAST_LEAVE_SOURCE_GROUP:
+        case MCAST_UNBLOCK_SOURCE:
                 return true;
         }
         return false;
@@ -861,9 +870,9 @@ 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:
@@ -928,7 +937,7 @@ 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;
@@ -960,9 +969,9 @@ 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:
@@ -1005,7 +1014,7 @@ 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;