1 files changed, 153 insertions, 30 deletions

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 3aeff0895669..780757b7a82f 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -14,6 +14,7 @@
 #include <linux/export.h>
 #include <linux/if_ether.h>
 #include <linux/igmp.h>
+#include <linux/in.h>
 #include <linux/jhash.h>
 #include <linux/kernel.h>
 #include <linux/log2.h>
@@ -29,6 +30,7 @@
 #include <net/ip.h>
 #include <net/switchdev.h>
 #if IS_ENABLED(CONFIG_IPV6)
+#include <linux/icmpv6.h>
 #include <net/ipv6.h>
 #include <net/mld.h>
 #include <net/ip6_checksum.h>
@@ -938,7 +940,7 @@ static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
 
 	for (i = 0; i < num; i++) {
 		len += sizeof(*grec);
-		if (!pskb_may_pull(skb, len))
+		if (!ip_mc_may_pull(skb, len))
 			return -EINVAL;
 
 		grec = (void *)(skb->data + len - sizeof(*grec));
@@ -946,7 +948,7 @@ static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
 		type = grec->grec_type;
 
 		len += ntohs(grec->grec_nsrcs) * 4;
-		if (!pskb_may_pull(skb, len))
+		if (!ip_mc_may_pull(skb, len))
 			return -EINVAL;
 
 		/* We treat this as an IGMPv2 report for now. */
@@ -985,15 +987,17 @@ static int br_ip6_multicast_mld2_report(struct net_bridge *br,
 					struct sk_buff *skb,
 					u16 vid)
 {
+	unsigned int nsrcs_offset;
 	const unsigned char *src;
 	struct icmp6hdr *icmp6h;
 	struct mld2_grec *grec;
+	unsigned int grec_len;
 	int i;
 	int len;
 	int num;
 	int err = 0;
 
-	if (!pskb_may_pull(skb, sizeof(*icmp6h)))
+	if (!ipv6_mc_may_pull(skb, sizeof(*icmp6h)))
 		return -EINVAL;
 
 	icmp6h = icmp6_hdr(skb);
@@ -1003,21 +1007,25 @@ static int br_ip6_multicast_mld2_report(struct net_bridge *br,
 	for (i = 0; i < num; i++) {
 		__be16 *nsrcs, _nsrcs;
 
-		nsrcs = skb_header_pointer(skb,
-					   len + offsetof(struct mld2_grec,
-							  grec_nsrcs),
+		nsrcs_offset = len + offsetof(struct mld2_grec, grec_nsrcs);
+
+		if (skb_transport_offset(skb) + ipv6_transport_len(skb) <
+		    nsrcs_offset + sizeof(_nsrcs))
+			return -EINVAL;
+
+		nsrcs = skb_header_pointer(skb, nsrcs_offset,
 					   sizeof(_nsrcs), &_nsrcs);
 		if (!nsrcs)
 			return -EINVAL;
 
-		if (!pskb_may_pull(skb,
-				   len + sizeof(*grec) +
-				   sizeof(struct in6_addr) * ntohs(*nsrcs)))
+		grec_len = sizeof(*grec) +
+			   sizeof(struct in6_addr) * ntohs(*nsrcs);
+
+		if (!ipv6_mc_may_pull(skb, len + grec_len))
 			return -EINVAL;
 
 		grec = (struct mld2_grec *)(skb->data + len);
-		len += sizeof(*grec) +
-		       sizeof(struct in6_addr) * ntohs(*nsrcs);
+		len += grec_len;
 
 		/* We treat these as MLDv1 reports for now. */
 		switch (grec->grec_type) {
@@ -1219,6 +1227,7 @@ static void br_ip4_multicast_query(struct net_bridge *br,
 				   struct sk_buff *skb,
 				   u16 vid)
 {
+	unsigned int transport_len = ip_transport_len(skb);
 	const struct iphdr *iph = ip_hdr(skb);
 	struct igmphdr *ih = igmp_hdr(skb);
 	struct net_bridge_mdb_entry *mp;
@@ -1228,7 +1237,6 @@ static void br_ip4_multicast_query(struct net_bridge *br,
 	struct br_ip saddr;
 	unsigned long max_delay;
 	unsigned long now = jiffies;
-	unsigned int offset = skb_transport_offset(skb);
 	__be32 group;
 
 	spin_lock(&br->multicast_lock);
@@ -1238,14 +1246,14 @@ static void br_ip4_multicast_query(struct net_bridge *br,
 
 	group = ih->group;
 
-	if (skb->len == offset + sizeof(*ih)) {
+	if (transport_len == sizeof(*ih)) {
 		max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
 
 		if (!max_delay) {
 			max_delay = 10 * HZ;
 			group = 0;
 		}
-	} else if (skb->len >= offset + sizeof(*ih3)) {
+	} else if (transport_len >= sizeof(*ih3)) {
 		ih3 = igmpv3_query_hdr(skb);
 		if (ih3->nsrcs)
 			goto out;
@@ -1296,6 +1304,7 @@ static int br_ip6_multicast_query(struct net_bridge *br,
 				  struct sk_buff *skb,
 				  u16 vid)
 {
+	unsigned int transport_len = ipv6_transport_len(skb);
 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
 	struct mld_msg *mld;
 	struct net_bridge_mdb_entry *mp;
@@ -1315,7 +1324,7 @@ static int br_ip6_multicast_query(struct net_bridge *br,
 	    (port && port->state == BR_STATE_DISABLED))
 		goto out;
 
-	if (skb->len == offset + sizeof(*mld)) {
+	if (transport_len == sizeof(*mld)) {
 		if (!pskb_may_pull(skb, offset + sizeof(*mld))) {
 			err = -EINVAL;
 			goto out;
@@ -1576,17 +1585,29 @@ static void br_multicast_pim(struct net_bridge *br,
 	br_multicast_mark_router(br, port);
 }
 
+static int br_ip4_multicast_mrd_rcv(struct net_bridge *br,
+				    struct net_bridge_port *port,
+				    struct sk_buff *skb)
+{
+	if (ip_hdr(skb)->protocol != IPPROTO_IGMP ||
+	    igmp_hdr(skb)->type != IGMP_MRDISC_ADV)
+		return -ENOMSG;
+
+	br_multicast_mark_router(br, port);
+
+	return 0;
+}
+
 static int br_multicast_ipv4_rcv(struct net_bridge *br,
 				 struct net_bridge_port *port,
 				 struct sk_buff *skb,
 				 u16 vid)
 {
-	struct sk_buff *skb_trimmed = NULL;
 	const unsigned char *src;
 	struct igmphdr *ih;
 	int err;
 
-	err = ip_mc_check_igmp(skb, &skb_trimmed);
+	err = ip_mc_check_igmp(skb);
 
 	if (err == -ENOMSG) {
 		if (!ipv4_is_local_multicast(ip_hdr(skb)->daddr)) {
@@ -1594,7 +1615,15 @@ static int br_multicast_ipv4_rcv(struct net_bridge *br,
 		} else if (pim_ipv4_all_pim_routers(ip_hdr(skb)->daddr)) {
 			if (ip_hdr(skb)->protocol == IPPROTO_PIM)
 				br_multicast_pim(br, port, skb);
+		} else if (ipv4_is_all_snoopers(ip_hdr(skb)->daddr)) {
+			err = br_ip4_multicast_mrd_rcv(br, port, skb);
+
+			if (err < 0 && err != -ENOMSG) {
+				br_multicast_err_count(br, port, skb->protocol);
+				return err;
+			}
 		}
+
 		return 0;
 	} else if (err < 0) {
 		br_multicast_err_count(br, port, skb->protocol);
@@ -1612,19 +1641,16 @@ static int br_multicast_ipv4_rcv(struct net_bridge *br,
 		err = br_ip4_multicast_add_group(br, port, ih->group, vid, src);
 		break;
 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
-		err = br_ip4_multicast_igmp3_report(br, port, skb_trimmed, vid);
+		err = br_ip4_multicast_igmp3_report(br, port, skb, vid);
 		break;
 	case IGMP_HOST_MEMBERSHIP_QUERY:
-		br_ip4_multicast_query(br, port, skb_trimmed, vid);
+		br_ip4_multicast_query(br, port, skb, vid);
 		break;
 	case IGMP_HOST_LEAVE_MESSAGE:
 		br_ip4_multicast_leave_group(br, port, ih->group, vid, src);
 		break;
 	}
 
-	if (skb_trimmed && skb_trimmed != skb)
-		kfree_skb(skb_trimmed);
-
 	br_multicast_count(br, port, skb, BR_INPUT_SKB_CB(skb)->igmp,
 			   BR_MCAST_DIR_RX);
 
@@ -1632,21 +1658,51 @@ static int br_multicast_ipv4_rcv(struct net_bridge *br,
 }
 
 #if IS_ENABLED(CONFIG_IPV6)
+static int br_ip6_multicast_mrd_rcv(struct net_bridge *br,
+				    struct net_bridge_port *port,
+				    struct sk_buff *skb)
+{
+	int ret;
+
+	if (ipv6_hdr(skb)->nexthdr != IPPROTO_ICMPV6)
+		return -ENOMSG;
+
+	ret = ipv6_mc_check_icmpv6(skb);
+	if (ret < 0)
+		return ret;
+
+	if (icmp6_hdr(skb)->icmp6_type != ICMPV6_MRDISC_ADV)
+		return -ENOMSG;
+
+	br_multicast_mark_router(br, port);
+
+	return 0;
+}
+
 static int br_multicast_ipv6_rcv(struct net_bridge *br,
 				 struct net_bridge_port *port,
 				 struct sk_buff *skb,
 				 u16 vid)
 {
-	struct sk_buff *skb_trimmed = NULL;
 	const unsigned char *src;
 	struct mld_msg *mld;
 	int err;
 
-	err = ipv6_mc_check_mld(skb, &skb_trimmed);
+	err = ipv6_mc_check_mld(skb);
 
 	if (err == -ENOMSG) {
 		if (!ipv6_addr_is_ll_all_nodes(&ipv6_hdr(skb)->daddr))
 			BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
+
+		if (ipv6_addr_is_all_snoopers(&ipv6_hdr(skb)->daddr)) {
+			err = br_ip6_multicast_mrd_rcv(br, port, skb);
+
+			if (err < 0 && err != -ENOMSG) {
+				br_multicast_err_count(br, port, skb->protocol);
+				return err;
+			}
+		}
+
 		return 0;
 	} else if (err < 0) {
 		br_multicast_err_count(br, port, skb->protocol);
@@ -1664,10 +1720,10 @@ static int br_multicast_ipv6_rcv(struct net_bridge *br,
 						 src);
 		break;
 	case ICMPV6_MLD2_REPORT:
-		err = br_ip6_multicast_mld2_report(br, port, skb_trimmed, vid);
+		err = br_ip6_multicast_mld2_report(br, port, skb, vid);
 		break;
 	case ICMPV6_MGM_QUERY:
-		err = br_ip6_multicast_query(br, port, skb_trimmed, vid);
+		err = br_ip6_multicast_query(br, port, skb, vid);
 		break;
 	case ICMPV6_MGM_REDUCTION:
 		src = eth_hdr(skb)->h_source;
@@ -1675,9 +1731,6 @@ static int br_multicast_ipv6_rcv(struct net_bridge *br,
 		break;
 	}
 
-	if (skb_trimmed && skb_trimmed != skb)
-		kfree_skb(skb_trimmed);
-
 	br_multicast_count(br, port, skb, BR_INPUT_SKB_CB(skb)->igmp,
 			   BR_MCAST_DIR_RX);
 
@@ -1781,6 +1834,68 @@ void br_multicast_init(struct net_bridge *br)
 	INIT_HLIST_HEAD(&br->mdb_list);
 }
 
+static void br_ip4_multicast_join_snoopers(struct net_bridge *br)
+{
+	struct in_device *in_dev = in_dev_get(br->dev);
+
+	if (!in_dev)
+		return;
+
+	ip_mc_inc_group(in_dev, htonl(INADDR_ALLSNOOPERS_GROUP));
+	in_dev_put(in_dev);
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static void br_ip6_multicast_join_snoopers(struct net_bridge *br)
+{
+	struct in6_addr addr;
+
+	ipv6_addr_set(&addr, htonl(0xff020000), 0, 0, htonl(0x6a));
+	ipv6_dev_mc_inc(br->dev, &addr);
+}
+#else
+static inline void br_ip6_multicast_join_snoopers(struct net_bridge *br)
+{
+}
+#endif
+
+static void br_multicast_join_snoopers(struct net_bridge *br)
+{
+	br_ip4_multicast_join_snoopers(br);
+	br_ip6_multicast_join_snoopers(br);
+}
+
+static void br_ip4_multicast_leave_snoopers(struct net_bridge *br)
+{
+	struct in_device *in_dev = in_dev_get(br->dev);
+
+	if (WARN_ON(!in_dev))
+		return;
+
+	ip_mc_dec_group(in_dev, htonl(INADDR_ALLSNOOPERS_GROUP));
+	in_dev_put(in_dev);
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static void br_ip6_multicast_leave_snoopers(struct net_bridge *br)
+{
+	struct in6_addr addr;
+
+	ipv6_addr_set(&addr, htonl(0xff020000), 0, 0, htonl(0x6a));
+	ipv6_dev_mc_dec(br->dev, &addr);
+}
+#else
+static inline void br_ip6_multicast_leave_snoopers(struct net_bridge *br)
+{
+}
+#endif
+
+static void br_multicast_leave_snoopers(struct net_bridge *br)
+{
+	br_ip4_multicast_leave_snoopers(br);
+	br_ip6_multicast_leave_snoopers(br);
+}
+
 static void __br_multicast_open(struct net_bridge *br,
 				struct bridge_mcast_own_query *query)
 {
@@ -1794,6 +1909,9 @@ static void __br_multicast_open(struct net_bridge *br,
 
 void br_multicast_open(struct net_bridge *br)
 {
+	if (br_opt_get(br, BROPT_MULTICAST_ENABLED))
+		br_multicast_join_snoopers(br);
+
 	__br_multicast_open(br, &br->ip4_own_query);
 #if IS_ENABLED(CONFIG_IPV6)
 	__br_multicast_open(br, &br->ip6_own_query);
@@ -1809,6 +1927,9 @@ void br_multicast_stop(struct net_bridge *br)
 	del_timer_sync(&br->ip6_other_query.timer);
 	del_timer_sync(&br->ip6_own_query.timer);
 #endif
+
+	if (br_opt_get(br, BROPT_MULTICAST_ENABLED))
+		br_multicast_leave_snoopers(br);
 }
 
 void br_multicast_dev_del(struct net_bridge *br)
@@ -1944,8 +2065,10 @@ int br_multicast_toggle(struct net_bridge *br, unsigned long val)
 
 	br_mc_disabled_update(br->dev, val);
 	br_opt_toggle(br, BROPT_MULTICAST_ENABLED, !!val);
-	if (!br_opt_get(br, BROPT_MULTICAST_ENABLED))
+	if (!br_opt_get(br, BROPT_MULTICAST_ENABLED)) {
+		br_multicast_leave_snoopers(br);
 		goto unlock;
+	}
 
 	if (!netif_running(br->dev))
 		goto unlock;