tcp: Annotate data-race around sk->sk_mark in tcp_v4_send_reset

This is a follow-up to 3c5b4d69c358 ("net: annotate data-races around
sk->sk_mark"). sk->sk_mark can be read and written without holding
the socket lock. IPv6 equivalent is already covered with READ_ONCE()
annotation in tcp_v6_send_response().

Fixes: 3c5b4d69c358 ("net: annotate data-races around sk->sk_mark")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/f459d1fc44f205e13f6d8bdca2c8bfb9902ffac9.1736244569.git.daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index a38c8b1f44dbd95fcea08bd81e0ceaa70177ac8a..c26f6c4b7bb4a39669e6b66a0f191f466a162fe5 100644 (file)
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -896,7 +896,7 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb,
        sock_net_set(ctl_sk, net);
        if (sk) {
                ctl_sk->sk_mark = (sk->sk_state == TCP_TIME_WAIT) ?
-                                  inet_twsk(sk)->tw_mark : sk->sk_mark;
+                                  inet_twsk(sk)->tw_mark : READ_ONCE(sk->sk_mark);
                ctl_sk->sk_priority = (sk->sk_state == TCP_TIME_WAIT) ?
                                   inet_twsk(sk)->tw_priority : READ_ONCE(sk->sk_priority);
                transmit_time = tcp_transmit_time(sk);