From e2d118a1cb5e60d077131a09db1d81b90a5295fe Mon Sep 17 00:00:00 2001 From: Lorenzo Colitti Date: Fri, 4 Nov 2016 02:23:43 +0900 Subject: net: inet: Support UID-based routing in IP protocols. - Use the UID in routing lookups made by protocol connect() and sendmsg() functions. - Make sure that routing lookups triggered by incoming packets (e.g., Path MTU discovery) take the UID of the socket into account. - For packets not associated with a userspace socket, (e.g., ping replies) use UID 0 inside the user namespace corresponding to the network namespace the socket belongs to. This allows all namespaces to apply routing and iptables rules to kernel-originated traffic in that namespaces by matching UID 0. This is better than using the UID of the kernel socket that is sending the traffic, because the UID of kernel sockets created at namespace creation time (e.g., the per-processor ICMP and TCP sockets) is the UID of the user that created the socket, which might not be mapped in the namespace. Tested: compiles allnoconfig, allyesconfig, allmodconfig Tested: https://android-review.googlesource.com/253302 Signed-off-by: Lorenzo Colitti Signed-off-by: David S. Miller --- net/ipv4/ip_output.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/ipv4/ip_output.c') diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 03e7f7310423..37dfacd340af 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -1587,7 +1587,8 @@ void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb, RT_SCOPE_UNIVERSE, ip_hdr(skb)->protocol, ip_reply_arg_flowi_flags(arg), daddr, saddr, - tcp_hdr(skb)->source, tcp_hdr(skb)->dest); + tcp_hdr(skb)->source, tcp_hdr(skb)->dest, + arg->uid); security_skb_classify_flow(skb, flowi4_to_flowi(&fl4)); rt = ip_route_output_key(net, &fl4); if (IS_ERR(rt)) -- cgit v1.2.3