1 files changed, 18 insertions, 10 deletions

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index f19e347f56f..543b3262d00 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -1430,7 +1430,7 @@ 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 sk_buff *skb2;
         struct ipv6hdr *ip6h;
         struct icmp6hdr *icmp6h;
         u8 nexthdr;
@@ -1469,15 +1469,15 @@ 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) {
@@ -1516,7 +1516,12 @@ 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;
+                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(skb2)->mrouters_only = 1;
                 err = br_ip6_multicast_add_group(br, port, &mld->mld_mca);
                 break;
@@ -1529,15 +1534,18 @@ 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