udp6: allow SO_MARK ctrl msg to affect routing

[ Upstream commit 42dcfd850e514b229d616a53dec06d0f2533217c ]

Commit c6af0c227a22 ("ip: support SO_MARK cmsg")
added propagation of SO_MARK from cmsg to skb->mark.
For IPv4 and raw sockets the mark also affects route
lookup, but in case of IPv6 the flow info is
initialized before cmsg is parsed.

Fixes: c6af0c227a22 ("ip: support SO_MARK cmsg")
Reported-and-tested-by: Xintong Hu <huxintong@fb.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 8d785232b4796b7cafe14a35dedcbb0aaa2c37c2..be6dc64ece29f8fe74bb5cf455f3ff249a41dba2 100644 (file)
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1435,7 +1435,6 @@ do_udp_sendmsg:
        if (!fl6.flowi6_oif)
                fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
 
-       fl6.flowi6_mark = ipc6.sockc.mark;
        fl6.flowi6_uid = sk->sk_uid;
 
        if (msg->msg_controllen) {
@@ -1471,6 +1470,7 @@ do_udp_sendmsg:
        ipc6.opt = opt;
 
        fl6.flowi6_proto = sk->sk_protocol;
+       fl6.flowi6_mark = ipc6.sockc.mark;
        fl6.daddr = *daddr;
        if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
                fl6.saddr = np->saddr;