Commit bf36267e authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

tcp: annotate data-race around queue->synflood_warned 



Annotate the lockless read of queue->synflood_warned.

Following xchg() has the needed data-race resolution.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 1d7322f2

net/ipv4/tcp_input.c

+1 −1
Original line number Diff line number Diff line
@@ -6841,7 +6841,7 @@ static bool tcp_syn_flood_action(const struct sock *sk, const char *proto) 
#endif

		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPREQQFULLDROP);



	if (!queue->synflood_warned && syncookies != 2 &&

	if (!READ_ONCE(queue->synflood_warned) && syncookies != 2 &&

	    xchg(&queue->synflood_warned, 1) == 0) {

		if (IS_ENABLED(CONFIG_IPV6) && sk->sk_family == AF_INET6) {

			net_info_ratelimited("%s: Possible SYN flooding on port [%pI6c]:%u. %s.\n",