Re: [IPSEC]: Fix reversed ICMP6 policy check

[Herbert Xu <herbert@gondor.apana.org.au>]

On Wed, Dec 12, 2007 at 06:48:30PM -0800, David Miller wrote:
> From: Herbert Xu <herbert@gondor.apana.org.au>
> Date: Thu, 13 Dec 2007 09:58:56 +0800
> 
> > [IPSEC]: Fix reversed ICMP6 policy check
> 
> Applied, thanks Herbert.

You're too quick :) Before you ask for an incremental patch, here's
a preemptive strike :)

[IPSEC]: Do not let packets pass when ICMP flag is off

This fixes a logical error in ICMP policy checks which lets
packets through if the state ICMP flag is off.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Cheers,
-- 
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
--
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 132e879..ccdef9a 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -978,10 +978,13 @@ int icmp_rcv(struct sk_buff *skb)
 	struct icmphdr *icmph;
 	struct rtable *rt = (struct rtable *)skb->dst;
 
-	if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb) && skb->sp &&
-	    skb->sp->xvec[skb->sp->len - 1]->props.flags & XFRM_STATE_ICMP) {
+	if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) {
 		int nh;
 
+		if (!(skb->sp && skb->sp->xvec[skb->sp->len - 1]->props.flags &
+				 XFRM_STATE_ICMP))
+			goto drop;
+
 		if (!pskb_may_pull(skb, sizeof(*icmph) + sizeof(struct iphdr)))
 			goto drop;
 
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index 64d78c9..bbf4162 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -646,10 +646,13 @@ static int icmpv6_rcv(struct sk_buff *skb)
 	struct icmp6hdr *hdr;
 	int type;
 
-	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb) && skb->sp &&
-	    skb->sp->xvec[skb->sp->len - 1]->props.flags & XFRM_STATE_ICMP) {
+	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
 		int nh;
 
+		if (!(skb->sp && skb->sp->xvec[skb->sp->len - 1]->props.flags &
+				 XFRM_STATE_ICMP))
+			goto drop_no_count;
+
 		if (!pskb_may_pull(skb, sizeof(*hdr) + sizeof(*orig_hdr)))
 			goto drop_no_count;