From 597b389bd8d496c050b7a02058702d27bf0ae3fa Mon Sep 17 00:00:00 2001 From: David Barmann Date: Thu, 8 Nov 2018 08:13:35 -0600 Subject: [PATCH] sock: Reset dst when changing sk_mark via setsockopt [ Upstream commit 50254256f382c56bde87d970f3d0d02fdb76ec70 ] When setting the SO_MARK socket option, if the mark changes, the dst needs to be reset so that a new route lookup is performed. This fixes the case where an application wants to change routing by setting a new sk_mark. If this is done after some packets have already been sent, the dst is cached and has no effect. Signed-off-by: David Barmann Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/core/sock.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/core/sock.c b/net/core/sock.c index d22493351407..9178c1654375 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -945,10 +945,12 @@ set_rcvbuf: clear_bit(SOCK_PASSSEC, &sock->flags); break; case SO_MARK: - if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) + if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { ret = -EPERM; - else + } else if (val != sk->sk_mark) { sk->sk_mark = val; + sk_dst_reset(sk); + } break; case SO_RXQ_OVFL: