From: Jakub Kicinski <kuba@kernel.org>
Date: Fri, 29 Oct 2021 15:51:34 +0000 (-0700)
Subject: udp6: allow SO_MARK ctrl msg to affect routing
X-Git-Tag: v5.10.80~200
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=366235d4bebc39363ed029176873097c66049954;p=thirdparty%2Fkernel%2Fstable.git

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 bae6b51a9bd46..8a1863146f34c 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1420,7 +1420,6 @@ 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) {
@@ -1456,6 +1455,7 @@ 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;