From 0652cac22ce3fa0c90e35d0a2862969fc394cb02 Mon Sep 17 00:00:00 2001 From: stephen hemminger Date: Fri, 22 Jul 2011 07:47:07 +0000 Subject: [PATCH] bridge: ignore bogus STP config packets If the message_age is already greater than the max_age, then the BPDU is bogus. Linux won't generate BPDU, but conformance tester or buggy implementation might. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- net/bridge/br_stp_bpdu.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/net/bridge/br_stp_bpdu.c b/net/bridge/br_stp_bpdu.c index 289646ec9b7b..b69232b3718b 100644 --- a/net/bridge/br_stp_bpdu.c +++ b/net/bridge/br_stp_bpdu.c @@ -210,6 +210,17 @@ void br_stp_rcv(const struct stp_proto *proto, struct sk_buff *skb, bpdu.hello_time = br_get_ticks(buf+28); bpdu.forward_delay = br_get_ticks(buf+30); + if (bpdu.message_age > bpdu.max_age) { + if (net_ratelimit()) + br_notice(p->br, + "port %u config from %pM" + " (message_age %ul > max_age %ul)\n", + p->port_no, + eth_hdr(skb)->h_source, + bpdu.message_age, bpdu.max_age); + goto out; + } + br_received_config_bpdu(p, &bpdu); } -- 2.20.1