From 59cae0092e4da753b5a2adb32933e0d1b223bcc5 Mon Sep 17 00:00:00 2001 From: Wei Yongjun Date: Thu, 2 Jul 2009 16:59:49 +0000 Subject: [PATCH] xfrm6: fix the proto and ports decode of sctp protocol The SCTP pushed the skb above the sctp chunk header, so the check of pskb_may_pull(skb, nh + offset + 1 - skb->data) in _decode_session6() will never return 0 and the ports decode of sctp will always fail. (nh + offset + 1 - skb->data < 0) Signed-off-by: Wei Yongjun Acked-by: Herbert Xu Signed-off-by: David S. Miller --- net/ipv6/xfrm6_policy.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c index b4b16a43f277..3a3c677bc0f2 100644 --- a/net/ipv6/xfrm6_policy.c +++ b/net/ipv6/xfrm6_policy.c @@ -157,7 +157,8 @@ _decode_session6(struct sk_buff *skb, struct flowi *fl, int reverse) ipv6_addr_copy(&fl->fl6_dst, reverse ? &hdr->saddr : &hdr->daddr); ipv6_addr_copy(&fl->fl6_src, reverse ? &hdr->daddr : &hdr->saddr); - while (pskb_may_pull(skb, nh + offset + 1 - skb->data)) { + while (nh + offset + 1 < skb->data || + pskb_may_pull(skb, nh + offset + 1 - skb->data)) { nh = skb_network_header(skb); exthdr = (struct ipv6_opt_hdr *)(nh + offset); @@ -177,7 +178,8 @@ _decode_session6(struct sk_buff *skb, struct flowi *fl, int reverse) case IPPROTO_TCP: case IPPROTO_SCTP: case IPPROTO_DCCP: - if (!onlyproto && pskb_may_pull(skb, nh + offset + 4 - skb->data)) { + if (!onlyproto && (nh + offset + 4 < skb->data || + pskb_may_pull(skb, nh + offset + 4 - skb->data))) { __be16 *ports = (__be16 *)exthdr; fl->fl_ip_sport = ports[!!reverse];