From: Changli Gao Date: Fri, 9 Jul 2010 15:33:25 +0000 (+0000) Subject: act_nat: not all of the ICMP packets need an IP header payload X-Git-Tag: v2.6.35-rc6~15^2~14 X-Git-Url: https://bbs.cooldavid.org/git/?p=net-next-2.6.git;a=commitdiff_plain;h=70c2efa5a32a7d38e66224844032160317fa7887 act_nat: not all of the ICMP packets need an IP header payload not all of the ICMP packets need an IP header payload, so we check the length of the skbs only when the packets should have an IP header payload. Based upon analysis and initial patch by Rodrigo Partearroyo González. Signed-off-by: Changli Gao Acked-by: Herbert Xu ---- net/sched/act_nat.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) Signed-off-by: David S. Miller --- diff --git a/net/sched/act_nat.c b/net/sched/act_nat.c index 570949417f3..724553e8ed7 100644 --- a/net/sched/act_nat.c +++ b/net/sched/act_nat.c @@ -205,7 +205,7 @@ static int tcf_nat(struct sk_buff *skb, struct tc_action *a, { struct icmphdr *icmph; - if (!pskb_may_pull(skb, ihl + sizeof(*icmph) + sizeof(*iph))) + if (!pskb_may_pull(skb, ihl + sizeof(*icmph))) goto drop; icmph = (void *)(skb_network_header(skb) + ihl); @@ -215,6 +215,9 @@ static int tcf_nat(struct sk_buff *skb, struct tc_action *a, (icmph->type != ICMP_PARAMETERPROB)) break; + if (!pskb_may_pull(skb, ihl + sizeof(*icmph) + sizeof(*iph))) + goto drop; + iph = (void *)(icmph + 1); if (egress) addr = iph->daddr;