diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index f19e347f56f6..543b3262d002 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