From 415b3334a21aa67806c52d1acf4e72e14f7f402f Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Fri, 22 Jul 2011 06:22:10 -0700 Subject: [PATCH] icmp: Fix regression in nexthop resolution during replies. icmp_route_lookup() uses the wrong flow parameters if the reverse session route lookup isn't used. So do not commit to the re-decoded flow until we actually make a final decision to use a real route saved in 'rt2'. Reported-by: Florian Westphal Signed-off-by: David S. Miller --- net/ipv4/icmp.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index 5395e45dcce6..23ef31baa1af 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -380,6 +380,7 @@ static struct rtable *icmp_route_lookup(struct net *net, struct icmp_bxm *param) { struct rtable *rt, *rt2; + struct flowi4 fl4_dec; int err; memset(fl4, 0, sizeof(*fl4)); @@ -408,19 +409,19 @@ static struct rtable *icmp_route_lookup(struct net *net, } else return rt; - err = xfrm_decode_session_reverse(skb_in, flowi4_to_flowi(fl4), AF_INET); + err = xfrm_decode_session_reverse(skb_in, flowi4_to_flowi(&fl4_dec), AF_INET); if (err) goto relookup_failed; - if (inet_addr_type(net, fl4->saddr) == RTN_LOCAL) { - rt2 = __ip_route_output_key(net, fl4); + if (inet_addr_type(net, fl4_dec.saddr) == RTN_LOCAL) { + rt2 = __ip_route_output_key(net, &fl4_dec); if (IS_ERR(rt2)) err = PTR_ERR(rt2); } else { struct flowi4 fl4_2 = {}; unsigned long orefdst; - fl4_2.daddr = fl4->saddr; + fl4_2.daddr = fl4_dec.saddr; rt2 = ip_route_output_key(net, &fl4_2); if (IS_ERR(rt2)) { err = PTR_ERR(rt2); @@ -428,7 +429,7 @@ static struct rtable *icmp_route_lookup(struct net *net, } /* Ugh! */ orefdst = skb_in->_skb_refdst; /* save old refdst */ - err = ip_route_input(skb_in, fl4->daddr, fl4->saddr, + err = ip_route_input(skb_in, fl4_dec.daddr, fl4_dec.saddr, RT_TOS(tos), rt2->dst.dev); dst_release(&rt2->dst); @@ -440,10 +441,11 @@ static struct rtable *icmp_route_lookup(struct net *net, goto relookup_failed; rt2 = (struct rtable *) xfrm_lookup(net, &rt2->dst, - flowi4_to_flowi(fl4), NULL, + flowi4_to_flowi(&fl4_dec), NULL, XFRM_LOOKUP_ICMP); if (!IS_ERR(rt2)) { dst_release(&rt->dst); + memcpy(fl4, &fl4_dec, sizeof(*fl4)); rt = rt2; } else if (PTR_ERR(rt2) == -EPERM) { if (rt)