Patch "net: setsockopt: fix IPV6_UNICAST_IF option for connected sockets" has been added to the 6.0-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    net: setsockopt: fix IPV6_UNICAST_IF option for connected sockets

to the 6.0-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     net-setsockopt-fix-ipv6_unicast_if-option-for-connec.patch
and it can be found in the queue-6.0 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 54ade678fd7b5bc4604e848d82866a684065fd52
Author: Richard Gobert <richardbgobert@xxxxxxxxx>
Date:   Thu Dec 8 15:54:46 2022 +0100

    net: setsockopt: fix IPV6_UNICAST_IF option for connected sockets
    
    [ Upstream commit 526682b458b1b56d2e0db027df535cb5cdcfde59 ]
    
    Change the behaviour of ip6_datagram_connect to consider the interface
    set by the IPV6_UNICAST_IF socket option, similarly to udpv6_sendmsg.
    
    This change is the IPv6 counterpart of the fix for IP_UNICAST_IF.
    The tests introduced by that patch showed that the incorrect
    behavior is present in IPv6 as well.
    This patch fixes the broken test.
    
    Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
    Link: https://lore.kernel.org/r/202210062117.c7eef1a3-oliver.sang@xxxxxxxxx
    Fixes: 0e4d354762ce ("net-next: Fix IP_UNICAST_IF option behavior for connected sockets")
    
    Signed-off-by: Richard Gobert <richardbgobert@xxxxxxxxx>
    Reviewed-by: David Ahern <dsahern@xxxxxxxxxx>
    Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index 5ecb56522f9d..ba28aeb7cade 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -42,24 +42,29 @@ static void ip6_datagram_flow_key_init(struct flowi6 *fl6, struct sock *sk)
 {
 	struct inet_sock *inet = inet_sk(sk);
 	struct ipv6_pinfo *np = inet6_sk(sk);
+	int oif = sk->sk_bound_dev_if;
 
 	memset(fl6, 0, sizeof(*fl6));
 	fl6->flowi6_proto = sk->sk_protocol;
 	fl6->daddr = sk->sk_v6_daddr;
 	fl6->saddr = np->saddr;
-	fl6->flowi6_oif = sk->sk_bound_dev_if;
 	fl6->flowi6_mark = sk->sk_mark;
 	fl6->fl6_dport = inet->inet_dport;
 	fl6->fl6_sport = inet->inet_sport;
 	fl6->flowlabel = np->flow_label;
 	fl6->flowi6_uid = sk->sk_uid;
 
-	if (!fl6->flowi6_oif)
-		fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
+	if (!oif)
+		oif = np->sticky_pktinfo.ipi6_ifindex;
 
-	if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr))
-		fl6->flowi6_oif = np->mcast_oif;
+	if (!oif) {
+		if (ipv6_addr_is_multicast(&fl6->daddr))
+			oif = np->mcast_oif;
+		else
+			oif = np->ucast_oif;
+	}
 
+	fl6->flowi6_oif = oif;
 	security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6));
 }