This is a note to let you know that I've just added the patch titled net: prefer socket bound to interface when not in VRF to the 5.10-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-prefer-socket-bound-to-interface-when-not-in-vrf.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 74ff364e6f25bd036fbc1693a86d1179f06e1322 Author: Mike Manning <mvrmanning@xxxxxxxxx> Date: Tue Oct 5 14:03:42 2021 +0100 net: prefer socket bound to interface when not in VRF [ Upstream commit 8d6c414cd2fb74aa6812e9bfec6178f8246c4f3a ] The commit 6da5b0f027a8 ("net: ensure unbound datagram socket to be chosen when not in a VRF") modified compute_score() so that a device match is always made, not just in the case of an l3mdev skb, then increments the score also for unbound sockets. This ensures that sockets bound to an l3mdev are never selected when not in a VRF. But as unbound and bound sockets are now scored equally, this results in the last opened socket being selected if there are matches in the default VRF for an unbound socket and a socket bound to a dev that is not an l3mdev. However, handling prior to this commit was to always select the bound socket in this case. Reinstate this handling by incrementing the score only for bound sockets. The required isolation due to choosing between an unbound socket and a socket bound to an l3mdev remains in place due to the device match always being made. The same approach is taken for compute_score() for stream sockets. Fixes: 6da5b0f027a8 ("net: ensure unbound datagram socket to be chosen when not in a VRF") Fixes: e78190581aff ("net: ensure unbound stream socket to be chosen when not in a VRF") Signed-off-by: Mike Manning <mmanning@xxxxxxxxxxxxxxxxxxx> Reviewed-by: David Ahern <dsahern@xxxxxxxxxx> Link: https://lore.kernel.org/r/cf0a8523-b362-1edf-ee78-eef63cbbb428@xxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c index 45fb450b4522..f3fd5c911ed0 100644 --- a/net/ipv4/inet_hashtables.c +++ b/net/ipv4/inet_hashtables.c @@ -242,8 +242,10 @@ static inline int compute_score(struct sock *sk, struct net *net, if (!inet_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif)) return -1; + score = sk->sk_bound_dev_if ? 2 : 1; - score = sk->sk_family == PF_INET ? 2 : 1; + if (sk->sk_family == PF_INET) + score++; if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id()) score++; } diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index bd7fd9b1f24c..655f0d8a13d3 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -390,7 +390,8 @@ static int compute_score(struct sock *sk, struct net *net, dif, sdif); if (!dev_match) return -1; - score += 4; + if (sk->sk_bound_dev_if) + score += 4; if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id()) score++; diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c index 55c290d55605..67c9114835c8 100644 --- a/net/ipv6/inet6_hashtables.c +++ b/net/ipv6/inet6_hashtables.c @@ -106,7 +106,7 @@ static inline int compute_score(struct sock *sk, struct net *net, if (!inet_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif)) return -1; - score = 1; + score = sk->sk_bound_dev_if ? 2 : 1; if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id()) score++; } diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 1943ae5103eb..bae6b51a9bd4 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -133,7 +133,8 @@ static int compute_score(struct sock *sk, struct net *net, dev_match = udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif); if (!dev_match) return -1; - score++; + if (sk->sk_bound_dev_if) + score++; if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id()) score++;