Commit b47bd8d2 authored Oct 05, 2014 by Daniel Borkmann Committed by David S. Miller Oct 06, 2014

ipv4: igmp: fix v3 general query drop monitor false positive



In case we find a general query with non-zero number of sources, we
are dropping the skb as it's malformed.

RFC3376, section 4.1.8. Number of Sources (N):

  This number is zero in a General Query or a Group-Specific Query,
  and non-zero in a Group-and-Source-Specific Query.

Therefore, reflect that by using kfree_skb() instead of consume_skb().

Fixes: d679c532 ("igmp: avoid drop_monitor false positives")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent ee637714

net/ipv4/igmp.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -931,7 +931,7 @@ static bool igmp_heard_query(struct in_device in_dev, struct sk_buff skb,
		in_dev->mr_qrv = ih3->qrv;
		if (!group) { /* general query */
		if (ih3->nsrcs)
		return false; /* no sources allowed */
		return true; /* no sources allowed */
		igmp_gq_start_timer(in_dev);
		return false;
		}

Admin message