diff options
| author | Patrick McHardy <kaber@trash.net> | 2006-02-15 15:10:22 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2006-02-15 15:10:22 -0800 |
| commit | 48d5cad87c3a4998d0bda16ccfb5c60dfe4de5fb (patch) | |
| tree | bfad91af72f4c522a44bab6133b540cda365d8c1 /net/ipv4/ip_output.c | |
| parent | 5ecfbae093f0c37311e89b29bfc0c9d586eace87 (diff) | |
| download | lwn-48d5cad87c3a4998d0bda16ccfb5c60dfe4de5fb.tar.gz lwn-48d5cad87c3a4998d0bda16ccfb5c60dfe4de5fb.zip | |
[XFRM]: Fix SNAT-related crash in xfrm4_output_finish
When a packet matching an IPsec policy is SNATed so it doesn't match any
policy anymore it looses its xfrm bundle, which makes xfrm4_output_finish
crash because of a NULL pointer dereference.
This patch directs these packets to the original output path instead. Since
the packets have already passed the POST_ROUTING hook, but need to start at
the beginning of the original output path which includes another
POST_ROUTING invocation, a flag is added to the IPCB to indicate that the
packet was rerouted and doesn't need to pass the POST_ROUTING hook again.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/ip_output.c')
| -rw-r--r-- | net/ipv4/ip_output.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 3324fbfe528a..57d290d89ec2 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -207,8 +207,10 @@ static inline int ip_finish_output(struct sk_buff *skb) { #if defined(CONFIG_NETFILTER) && defined(CONFIG_XFRM) /* Policy lookup after SNAT yielded a new policy */ - if (skb->dst->xfrm != NULL) - return xfrm4_output_finish(skb); + if (skb->dst->xfrm != NULL) { + IPCB(skb)->flags |= IPSKB_REROUTED; + return dst_output(skb); + } #endif if (skb->len > dst_mtu(skb->dst) && !(skb_shinfo(skb)->ufo_size || skb_shinfo(skb)->tso_size)) @@ -271,8 +273,9 @@ int ip_mc_output(struct sk_buff *skb) newskb->dev, ip_dev_loopback_xmit); } - return NF_HOOK(PF_INET, NF_IP_POST_ROUTING, skb, NULL, skb->dev, - ip_finish_output); + return NF_HOOK_COND(PF_INET, NF_IP_POST_ROUTING, skb, NULL, skb->dev, + ip_finish_output, + !(IPCB(skb)->flags & IPSKB_REROUTED)); } int ip_output(struct sk_buff *skb) @@ -284,8 +287,9 @@ int ip_output(struct sk_buff *skb) skb->dev = dev; skb->protocol = htons(ETH_P_IP); - return NF_HOOK(PF_INET, NF_IP_POST_ROUTING, skb, NULL, dev, - ip_finish_output); + return NF_HOOK_COND(PF_INET, NF_IP_POST_ROUTING, skb, NULL, dev, + ip_finish_output, + !(IPCB(skb)->flags & IPSKB_REROUTED)); } int ip_queue_xmit(struct sk_buff *skb, int ipfragok) |