From 9fc3bbb4a752f108cf096d96640f3b548bbbce6c Mon Sep 17 00:00:00 2001 From: Joel Sing Date: Mon, 3 Jan 2011 20:24:20 +0000 Subject: ipv4/route.c: respect prefsrc for local routes The preferred source address is currently ignored for local routes, which results in all local connections having a src address that is the same as the local dst address. Fix this by respecting the preferred source address when it is provided for local routes. This bug can be demonstrated as follows: # ifconfig dummy0 192.168.0.1 # ip route show table local | grep local.*dummy0 local 192.168.0.1 dev dummy0 proto kernel scope host src 192.168.0.1 # ip route change table local local 192.168.0.1 dev dummy0 \ proto kernel scope host src 127.0.0.1 # ip route show table local | grep local.*dummy0 local 192.168.0.1 dev dummy0 proto kernel scope host src 127.0.0.1 We now establish a local connection and verify the source IP address selection: # nc -l 192.168.0.1 3128 & # nc 192.168.0.1 3128 & # netstat -ant | grep 192.168.0.1:3128.*EST tcp 0 0 192.168.0.1:3128 192.168.0.1:33228 ESTABLISHED tcp 0 0 192.168.0.1:33228 192.168.0.1:3128 ESTABLISHED Signed-off-by: Joel Sing Signed-off-by: David S. Miller --- net/ipv4/route.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/net/ipv4/route.c b/net/ipv4/route.c index df948b0f1ac9..93bfd95584f4 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -2649,8 +2649,12 @@ static int ip_route_output_slow(struct net *net, struct rtable **rp, } if (res.type == RTN_LOCAL) { - if (!fl.fl4_src) - fl.fl4_src = fl.fl4_dst; + if (!fl.fl4_src) { + if (res.fi->fib_prefsrc) + fl.fl4_src = res.fi->fib_prefsrc; + else + fl.fl4_src = fl.fl4_dst; + } dev_out = net->loopback_dev; fl.oif = dev_out->ifindex; res.fi = NULL; -- cgit v1.2.3-70-g09d2