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

This is a follow-up to 3c5b4d6 ("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: 3c5b4d6 ("net: annotate data-races around sk->sk_mark")
Signed-off-by: Daniel Borkmann <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Link: https://patch.msgid.link/f459d1fc44f205e13f6d8bdca2c8bfb9902ffac9.1736244569.git.daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <[email protected]>

Author: borkmann

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);