From a8801799c6975601fd58ae62f48964caec2eb83f Mon Sep 17 00:00:00 2001 From: Florian Larysch Date: Mon, 3 Apr 2017 16:46:09 +0200 Subject: [PATCH] net: ipv4: fix multipath RTM_GETROUTE behavior when iif is given inet_rtm_getroute synthesizes a skeletal ICMP skb, which is passed to ip_route_input when iif is given. If a multipath route is present for the designated destination, ip_multipath_icmp_hash ends up being called, which uses the source/destination addresses within the skb to calculate a hash. However, those are not set in the synthetic skb, causing it to return an arbitrary and incorrect result. Instead, use UDP, which gets no such special treatment. Signed-off-by: Florian Larysch Signed-off-by: David S. Miller --- net/ipv4/route.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 8471dd116771..acd69cfe2951 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -2620,7 +2620,7 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh) skb_reset_network_header(skb); /* Bugfix: need to give ip_route_input enough of an IP header to not gag. */ - ip_hdr(skb)->protocol = IPPROTO_ICMP; + ip_hdr(skb)->protocol = IPPROTO_UDP; skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr)); src = tb[RTA_SRC] ? nla_get_in_addr(tb[RTA_SRC]) : 0; -- 2.20.1