1 files changed, 110 insertions, 73 deletions

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index eb5b256ffc88..2d85ca7111d3 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -33,11 +33,13 @@
 
 #include "br_private.h"
 
+#define mlock_dereference(X, br) \
+        rcu_dereference_protected(X, lockdep_is_held(&br->multicast_lock))
+
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-static inline int ipv6_is_local_multicast(const struct in6_addr *addr)
+static inline int ipv6_is_transient_multicast(const struct in6_addr *addr)
 {
-        if (ipv6_addr_is_multicast(addr) &&
-            IPV6_ADDR_MC_SCOPE(addr) <= IPV6_ADDR_SCOPE_LINKLOCAL)
+        if (ipv6_addr_is_multicast(addr) && IPV6_ADDR_MC_FLAG_TRANSIENT(addr))
                 return 1;
         return 0;
 }
@@ -135,7 +137,7 @@ static struct net_bridge_mdb_entry *br_mdb_ip6_get(
 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
                                         struct sk_buff *skb)
 {
-        struct net_bridge_mdb_htable *mdb = br->mdb;
+        struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
         struct br_ip ip;
 
         if (br->multicast_disabled)
@@ -229,13 +231,13 @@ static void br_multicast_group_expired(unsigned long data)
         if (!netif_running(br->dev) || timer_pending(&mp->timer))
                 goto out;
 
-        if (!hlist_unhashed(&mp->mglist))
-                hlist_del_init(&mp->mglist);
+        mp->mglist = false;
 
         if (mp->ports)
                 goto out;
 
-        mdb = br->mdb;
+        mdb = mlock_dereference(br->mdb, br);
+
         hlist_del_rcu(&mp->hlist[mdb->ver]);
         mdb->size--;
 
@@ -249,16 +251,20 @@ out:
 static void br_multicast_del_pg(struct net_bridge *br,
                                 struct net_bridge_port_group *pg)
 {
-        struct net_bridge_mdb_htable *mdb = br->mdb;
+        struct net_bridge_mdb_htable *mdb;
         struct net_bridge_mdb_entry *mp;
         struct net_bridge_port_group *p;
-        struct net_bridge_port_group **pp;
+        struct net_bridge_port_group __rcu **pp;
+
+        mdb = mlock_dereference(br->mdb, br);
 
         mp = br_mdb_ip_get(mdb, &pg->addr);
         if (WARN_ON(!mp))
                 return;
 
-        for (pp = &mp->ports; (p = *pp); pp = &p->next) {
+        for (pp = &mp->ports;
+             (p = mlock_dereference(*pp, br)) != NULL;
+             pp = &p->next) {
                 if (p != pg)
                         continue;
 
@@ -268,7 +274,7 @@ static void br_multicast_del_pg(struct net_bridge *br,
                 del_timer(&p->query_timer);
                 call_rcu_bh(&p->rcu, br_multicast_free_pg);
 
-                if (!mp->ports && hlist_unhashed(&mp->mglist) &&
+                if (!mp->ports && !mp->mglist &&
                     netif_running(br->dev))
                         mod_timer(&mp->timer, jiffies);
 
@@ -294,10 +300,10 @@ out:
         spin_unlock(&br->multicast_lock);
 }
 
-static int br_mdb_rehash(struct net_bridge_mdb_htable **mdbp, int max,
+static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
                          int elasticity)
 {
-        struct net_bridge_mdb_htable *old = *mdbp;
+        struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
         struct net_bridge_mdb_htable *mdb;
         int err;
 
@@ -407,7 +413,7 @@ out:
 
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
-                                                    struct in6_addr *group)
+                                                    const struct in6_addr *group)
 {
         struct sk_buff *skb;
         struct ipv6hdr *ip6h;
@@ -428,7 +434,6 @@ static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
         eth = eth_hdr(skb);
 
         memcpy(eth->h_source, br->dev->dev_addr, 6);
-        ipv6_eth_mc_map(group, eth->h_dest);
         eth->h_proto = htons(ETH_P_IPV6);
         skb_put(skb, sizeof(*eth));
 
@@ -437,11 +442,13 @@ static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
         ip6h = ipv6_hdr(skb);
 
         *(__force __be32 *)ip6h = htonl(0x60000000);
-        ip6h->payload_len = 8 + sizeof(*mldq);
+        ip6h->payload_len = htons(8 + sizeof(*mldq));
         ip6h->nexthdr = IPPROTO_HOPOPTS;
         ip6h->hop_limit = 1;
-        ipv6_addr_set(&ip6h->saddr, 0, 0, 0, 0);
         ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
+        ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
+                           &ip6h->saddr);
+        ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
 
         hopopt = (u8 *)(ip6h + 1);
         hopopt[0] = IPPROTO_ICMPV6;             /* next hdr */
@@ -520,7 +527,7 @@ static void br_multicast_group_query_expired(unsigned long data)
         struct net_bridge *br = mp->br;
 
         spin_lock(&br->multicast_lock);
-        if (!netif_running(br->dev) || hlist_unhashed(&mp->mglist) ||
+        if (!netif_running(br->dev) || !mp->mglist ||
             mp->queries_sent >= br->multicast_last_member_count)
                 goto out;
 
@@ -569,7 +576,7 @@ static struct net_bridge_mdb_entry *br_multicast_get_group(
         struct net_bridge *br, struct net_bridge_port *port,
         struct br_ip *group, int hash)
 {
-        struct net_bridge_mdb_htable *mdb = br->mdb;
+        struct net_bridge_mdb_htable *mdb;
         struct net_bridge_mdb_entry *mp;
         struct hlist_node *p;
         unsigned count = 0;
@@ -577,6 +584,7 @@ static struct net_bridge_mdb_entry *br_multicast_get_group(
         int elasticity;
         int err;
 
+        mdb = rcu_dereference_protected(br->mdb, 1);
         hlist_for_each_entry(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
                 count++;
                 if (unlikely(br_ip_equal(group, &mp->addr)))
@@ -642,13 +650,16 @@ static struct net_bridge_mdb_entry *br_multicast_new_group(
         struct net_bridge *br, struct net_bridge_port *port,
         struct br_ip *group)
 {
-        struct net_bridge_mdb_htable *mdb = br->mdb;
+        struct net_bridge_mdb_htable *mdb;
         struct net_bridge_mdb_entry *mp;
         int hash;
+        int err;
 
+        mdb = rcu_dereference_protected(br->mdb, 1);
         if (!mdb) {
-                if (br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0))
-                        return NULL;
+                err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
+                if (err)
+                        return ERR_PTR(err);
                 goto rehash;
         }
 
@@ -660,7 +671,7 @@ static struct net_bridge_mdb_entry *br_multicast_new_group(
 
         case -EAGAIN:
 rehash:
-                mdb = br->mdb;
+                mdb = rcu_dereference_protected(br->mdb, 1);
                 hash = br_ip_hash(mdb, group);
                 break;
 
@@ -670,7 +681,7 @@ rehash:
 
         mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
         if (unlikely(!mp))
-                goto out;
+                return ERR_PTR(-ENOMEM);
 
         mp->br = br;
         mp->addr = *group;
@@ -692,7 +703,7 @@ static int br_multicast_add_group(struct net_bridge *br,
 {
         struct net_bridge_mdb_entry *mp;
         struct net_bridge_port_group *p;
-        struct net_bridge_port_group **pp;
+        struct net_bridge_port_group __rcu **pp;
         unsigned long now = jiffies;
         int err;
 
@@ -703,16 +714,18 @@ static int br_multicast_add_group(struct net_bridge *br,
 
         mp = br_multicast_new_group(br, port, group);
         err = PTR_ERR(mp);
-        if (unlikely(IS_ERR(mp) || !mp))
+        if (IS_ERR(mp))
                 goto err;
 
         if (!port) {
-                hlist_add_head(&mp->mglist, &br->mglist);
+                mp->mglist = true;
                 mod_timer(&mp->timer, now + br->multicast_membership_interval);
                 goto out;
         }
 
-        for (pp = &mp->ports; (p = *pp); pp = &p->next) {
+        for (pp = &mp->ports;
+             (p = mlock_dereference(*pp, br)) != NULL;
+             pp = &p->next) {
                 if (p->port == port)
                         goto found;
                 if ((unsigned long)p->port < (unsigned long)port)
@@ -767,11 +780,11 @@ static int br_ip6_multicast_add_group(struct net_bridge *br,
 {
         struct br_ip br_group;
 
-        if (ipv6_is_local_multicast(group))
+        if (!ipv6_is_transient_multicast(group))
                 return 0;
 
         ipv6_addr_copy(&br_group.u.ip6, group);
-        br_group.proto = htons(ETH_P_IP);
+        br_group.proto = htons(ETH_P_IPV6);
 
         return br_multicast_add_group(br, port, &br_group);
 }
@@ -1000,18 +1013,19 @@ static int br_ip6_multicast_mld2_report(struct net_bridge *br,
 
                 nsrcs = skb_header_pointer(skb,
                                            len + offsetof(struct mld2_grec,
-                                                          grec_mca),
+                                                          grec_nsrcs),
                                            sizeof(_nsrcs), &_nsrcs);
                 if (!nsrcs)
                         return -EINVAL;
 
                 if (!pskb_may_pull(skb,
                                    len + sizeof(*grec) +
-                                   sizeof(struct in6_addr) * (*nsrcs)))
+                                   sizeof(struct in6_addr) * ntohs(*nsrcs)))
                         return -EINVAL;
 
                 grec = (struct mld2_grec *)(skb->data + len);
-                len += sizeof(*grec) + sizeof(struct in6_addr) * (*nsrcs);
+                len += sizeof(*grec) +
+                       sizeof(struct in6_addr) * ntohs(*nsrcs);
 
                 /* We treat these as MLDv1 reports for now. */
                 switch (grec->grec_type) {
@@ -1101,12 +1115,12 @@ static int br_ip4_multicast_query(struct net_bridge *br,
                                   struct net_bridge_port *port,
                                   struct sk_buff *skb)
 {
-        struct iphdr *iph = ip_hdr(skb);
+        const struct iphdr *iph = ip_hdr(skb);
         struct igmphdr *ih = igmp_hdr(skb);
         struct net_bridge_mdb_entry *mp;
         struct igmpv3_query *ih3;
         struct net_bridge_port_group *p;
-        struct net_bridge_port_group **pp;
+        struct net_bridge_port_group __rcu **pp;
         unsigned long max_delay;
         unsigned long now = jiffies;
         __be32 group;
@@ -1145,23 +1159,25 @@ static int br_ip4_multicast_query(struct net_bridge *br,
         if (!group)
                 goto out;
 
-        mp = br_mdb_ip4_get(br->mdb, group);
+        mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group);
         if (!mp)
                 goto out;
 
         max_delay *= br->multicast_last_member_count;
 
-        if (!hlist_unhashed(&mp->mglist) &&
+        if (mp->mglist &&
             (timer_pending(&mp->timer) ?
              time_after(mp->timer.expires, now + max_delay) :
              try_to_del_timer_sync(&mp->timer) >= 0))
                 mod_timer(&mp->timer, now + max_delay);
 
-        for (pp = &mp->ports; (p = *pp); pp = &p->next) {
+        for (pp = &mp->ports;
+             (p = mlock_dereference(*pp, br)) != NULL;
+             pp = &p->next) {
                 if (timer_pending(&p->timer) ?
                     time_after(p->timer.expires, now + max_delay) :
                     try_to_del_timer_sync(&p->timer) >= 0)
-                        mod_timer(&mp->timer, now + max_delay);
+                        mod_timer(&p->timer, now + max_delay);
         }
 
 out:
@@ -1174,14 +1190,15 @@ static int br_ip6_multicast_query(struct net_bridge *br,
                                   struct net_bridge_port *port,
                                   struct sk_buff *skb)
 {
-        struct ipv6hdr *ip6h = ipv6_hdr(skb);
+        const struct ipv6hdr *ip6h = ipv6_hdr(skb);
         struct mld_msg *mld = (struct mld_msg *) icmp6_hdr(skb);
         struct net_bridge_mdb_entry *mp;
         struct mld2_query *mld2q;
-        struct net_bridge_port_group *p, **pp;
+        struct net_bridge_port_group *p;
+        struct net_bridge_port_group __rcu **pp;
         unsigned long max_delay;
         unsigned long now = jiffies;
-        struct in6_addr *group = NULL;
+        const struct in6_addr *group = NULL;
         int err = 0;
 
         spin_lock(&br->multicast_lock);
@@ -1214,22 +1231,24 @@ static int br_ip6_multicast_query(struct net_bridge *br,
         if (!group)
                 goto out;
 
-        mp = br_mdb_ip6_get(br->mdb, group);
+        mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group);
         if (!mp)
                 goto out;
 
         max_delay *= br->multicast_last_member_count;
-        if (!hlist_unhashed(&mp->mglist) &&
+        if (mp->mglist &&
             (timer_pending(&mp->timer) ?
              time_after(mp->timer.expires, now + max_delay) :
              try_to_del_timer_sync(&mp->timer) >= 0))
                 mod_timer(&mp->timer, now + max_delay);
 
-        for (pp = &mp->ports; (p = *pp); pp = &p->next) {
+        for (pp = &mp->ports;
+             (p = mlock_dereference(*pp, br)) != NULL;
+             pp = &p->next) {
                 if (timer_pending(&p->timer) ?
                     time_after(p->timer.expires, now + max_delay) :
                     try_to_del_timer_sync(&p->timer) >= 0)
-                        mod_timer(&mp->timer, now + max_delay);
+                        mod_timer(&p->timer, now + max_delay);
         }
 
 out:
@@ -1254,7 +1273,7 @@ static void br_multicast_leave_group(struct net_bridge *br,
             timer_pending(&br->multicast_querier_timer))
                 goto out;
 
-        mdb = br->mdb;
+        mdb = mlock_dereference(br->mdb, br);
         mp = br_mdb_ip_get(mdb, group);
         if (!mp)
                 goto out;
@@ -1264,7 +1283,7 @@ static void br_multicast_leave_group(struct net_bridge *br,
                      br->multicast_last_member_interval;
 
         if (!port) {
-                if (!hlist_unhashed(&mp->mglist) &&
+                if (mp->mglist &&
                     (timer_pending(&mp->timer) ?
                      time_after(mp->timer.expires, time) :
                      try_to_del_timer_sync(&mp->timer) >= 0)) {
@@ -1277,7 +1296,9 @@ static void br_multicast_leave_group(struct net_bridge *br,
                 goto out;
         }
 
-        for (p = mp->ports; p; p = p->next) {
+        for (p = mlock_dereference(mp->ports, br);
+             p != NULL;
+             p = mlock_dereference(p->next, br)) {
                 if (p->port != port)
                         continue;
 
@@ -1320,7 +1341,7 @@ static void br_ip6_multicast_leave_group(struct net_bridge *br,
 {
         struct br_ip br_group;
 
-        if (ipv6_is_local_multicast(group))
+        if (!ipv6_is_transient_multicast(group))
                 return;
 
         ipv6_addr_copy(&br_group.u.ip6, group);
@@ -1335,7 +1356,7 @@ static int br_multicast_ipv4_rcv(struct net_bridge *br,
                                  struct sk_buff *skb)
 {
         struct sk_buff *skb2 = skb;
-        struct iphdr *iph;
+        const struct iphdr *iph;
         struct igmphdr *ih;
         unsigned len;
         unsigned offset;
@@ -1358,8 +1379,11 @@ static int br_multicast_ipv4_rcv(struct net_bridge *br,
         if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
                 return -EINVAL;
 
-        if (iph->protocol != IPPROTO_IGMP)
+        if (iph->protocol != IPPROTO_IGMP) {
+                if ((iph->daddr & IGMP_LOCAL_GROUP_MASK) != IGMP_LOCAL_GROUP)
+                        BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
                 return 0;
+        }
 
         len = ntohs(iph->tot_len);
         if (skb->len < len || len < ip_hdrlen(skb))
@@ -1403,7 +1427,7 @@ static int br_multicast_ipv4_rcv(struct net_bridge *br,
         switch (ih->type) {
         case IGMP_HOST_MEMBERSHIP_REPORT:
         case IGMPV2_HOST_MEMBERSHIP_REPORT:
-                BR_INPUT_SKB_CB(skb2)->mrouters_only = 1;
+                BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
                 err = br_ip4_multicast_add_group(br, port, ih->group);
                 break;
         case IGMPV3_HOST_MEMBERSHIP_REPORT:
@@ -1430,8 +1454,8 @@ static int br_multicast_ipv6_rcv(struct net_bridge *br,
                                  struct net_bridge_port *port,
                                  struct sk_buff *skb)
 {
-        struct sk_buff *skb2 = skb;
-        struct ipv6hdr *ip6h;
+        struct sk_buff *skb2;
+        const struct ipv6hdr *ip6h;
         struct icmp6hdr *icmp6h;
         u8 nexthdr;
         unsigned len;
@@ -1454,7 +1478,7 @@ static int br_multicast_ipv6_rcv(struct net_bridge *br,
             ip6h->payload_len == 0)
                 return 0;
 
-        len = ntohs(ip6h->payload_len);
+        len = ntohs(ip6h->payload_len) + sizeof(*ip6h);
         if (skb->len < len)
                 return -EINVAL;
 
@@ -1469,15 +1493,15 @@ static int br_multicast_ipv6_rcv(struct net_bridge *br,
         if (!skb2)
                 return -ENOMEM;
 
+        err = -EINVAL;
+        if (!pskb_may_pull(skb2, offset + sizeof(struct icmp6hdr)))
+                goto out;
+
         len -= offset - skb_network_offset(skb2);
 
         __skb_pull(skb2, offset);
         skb_reset_transport_header(skb2);
 
-        err = -EINVAL;
-        if (!pskb_may_pull(skb2, sizeof(*icmp6h)))
-                goto out;
-
         icmp6h = icmp6_hdr(skb2);
 
         switch (icmp6h->icmp6_type) {
@@ -1516,8 +1540,13 @@ static int br_multicast_ipv6_rcv(struct net_bridge *br,
         switch (icmp6h->icmp6_type) {
         case ICMPV6_MGM_REPORT:
             {
-                struct mld_msg *mld = (struct mld_msg *)icmp6h;
-                BR_INPUT_SKB_CB(skb2)->mrouters_only = 1;
+                struct mld_msg *mld;
+                if (!pskb_may_pull(skb2, sizeof(*mld))) {
+                        err = -EINVAL;
+                        goto out;
+                }
+                mld = (struct mld_msg *)skb_transport_header(skb2);
+                BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
                 err = br_ip6_multicast_add_group(br, port, &mld->mld_mca);
                 break;
             }
@@ -1529,15 +1558,18 @@ static int br_multicast_ipv6_rcv(struct net_bridge *br,
                 break;
         case ICMPV6_MGM_REDUCTION:
             {
-                struct mld_msg *mld = (struct mld_msg *)icmp6h;
+                struct mld_msg *mld;
+                if (!pskb_may_pull(skb2, sizeof(*mld))) {
+                        err = -EINVAL;
+                        goto out;
+                }
+                mld = (struct mld_msg *)skb_transport_header(skb2);
                 br_ip6_multicast_leave_group(br, port, &mld->mld_mca);
             }
         }
 
 out:
-        __skb_push(skb2, offset);
-        if (skb2 != skb)
-                kfree_skb(skb2);
+        kfree_skb(skb2);
         return err;
 }
 #endif
@@ -1625,7 +1657,7 @@ void br_multicast_stop(struct net_bridge *br)
         del_timer_sync(&br->multicast_query_timer);
 
         spin_lock_bh(&br->multicast_lock);
-        mdb = br->mdb;
+        mdb = mlock_dereference(br->mdb, br);
         if (!mdb)
                 goto out;
 
@@ -1729,6 +1761,7 @@ int br_multicast_toggle(struct net_bridge *br, unsigned long val)
 {
         struct net_bridge_port *port;
         int err = 0;
+        struct net_bridge_mdb_htable *mdb;
 
         spin_lock(&br->multicast_lock);
         if (br->multicast_disabled == !val)
@@ -1741,15 +1774,16 @@ int br_multicast_toggle(struct net_bridge *br, unsigned long val)
         if (!netif_running(br->dev))
                 goto unlock;
 
-        if (br->mdb) {
-                if (br->mdb->old) {
+        mdb = mlock_dereference(br->mdb, br);
+        if (mdb) {
+                if (mdb->old) {
                         err = -EEXIST;
 rollback:
                         br->multicast_disabled = !!val;
                         goto unlock;
                 }
 
-                err = br_mdb_rehash(&br->mdb, br->mdb->max,
+                err = br_mdb_rehash(&br->mdb, mdb->max,
                                     br->hash_elasticity);
                 if (err)
                         goto rollback;
@@ -1774,6 +1808,7 @@ int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
 {
         int err = -ENOENT;
         u32 old;
+        struct net_bridge_mdb_htable *mdb;
 
         spin_lock(&br->multicast_lock);
         if (!netif_running(br->dev))
@@ -1782,7 +1817,9 @@ int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
         err = -EINVAL;
         if (!is_power_of_2(val))
                 goto unlock;
-        if (br->mdb && val < br->mdb->size)
+
+        mdb = mlock_dereference(br->mdb, br);
+        if (mdb && val < mdb->size)
                 goto unlock;
 
         err = 0;
@@ -1790,8 +1827,8 @@ int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
         old = br->hash_max;
         br->hash_max = val;
 
-        if (br->mdb) {
-                if (br->mdb->old) {
+        if (mdb) {
+                if (mdb->old) {
                         err = -EEXIST;
 rollback:
                         br->hash_max = old;