Commit 3b26a5d0 authored Jul 02, 2019 by Nikolay Aleksandrov Committed by David S. Miller Jul 02, 2019

net: bridge: mcast: fix stale ipv6 hdr pointer when handling v6 query



We get a pointer to the ipv6 hdr in br_ip6_multicast_query but we may
call pskb_may_pull afterwards and end up using a stale pointer.
So use the header directly, it's just 1 place where it's needed.

Fixes: 08b202b6 ("bridge br_multicast: IPv6 MLD support.")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Tested-by: Martin Weinelt <martin@linuxlounge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent e57f6185

net/bridge/br_multicast.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -1279,7 +1279,6 @@ static int br_ip6_multicast_query(struct net_bridge *br,
		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;
		struct mld2_query *mld2q;
		@@ -1323,7 +1322,7 @@ static int br_ip6_multicast_query(struct net_bridge *br,

		if (is_general_query) {
		saddr.proto = htons(ETH_P_IPV6);
		saddr.u.ip6 = ip6h->saddr;
		saddr.u.ip6 = ipv6_hdr(skb)->saddr;

		br_multicast_query_received(br, port, &br->ip6_other_query,
		&saddr, max_delay);

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