Commit 285975dd authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net: annotate data-races around sk->sk_{rcv|snd}timeo 



sk_getsockopt() runs without locks, we must add annotations
to sk->sk_rcvtimeo and sk->sk_sndtimeo.

In the future we might allow fetching these fields before
we lock the socket in TCP fast path.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e6d12bdb

net/core/sock.c

+14 −10
Original line number Diff line number Diff line
@@ -429,6 +429,7 @@ static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen, 
{

	struct __kernel_sock_timeval tv;

	int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);

	long val;



	if (err)

		return err;
@@ -439,7 +440,7 @@ static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen, 
	if (tv.tv_sec < 0) {

		static int warned __read_mostly;



		*timeo_p = 0;

		WRITE_ONCE(*timeo_p, 0);

		if (warned < 10 && net_ratelimit()) {

			warned++;

			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
@@ -447,11 +448,12 @@ static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen, 
		}

		return 0;

	}

	*timeo_p = MAX_SCHEDULE_TIMEOUT;

	if (tv.tv_sec == 0 && tv.tv_usec == 0)

		return 0;

	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))

		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ);

	val = MAX_SCHEDULE_TIMEOUT;

	if ((tv.tv_sec || tv.tv_usec) &&

	    (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)))

		val = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec,

						    USEC_PER_SEC / HZ);

	WRITE_ONCE(*timeo_p, val);

	return 0;

}
@@ -813,9 +815,9 @@ void sock_set_sndtimeo(struct sock *sk, s64 secs) 
{

	lock_sock(sk);

	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)

		sk->sk_sndtimeo = secs * HZ;

		WRITE_ONCE(sk->sk_sndtimeo, secs * HZ);

	else

		sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;

		WRITE_ONCE(sk->sk_sndtimeo, MAX_SCHEDULE_TIMEOUT);

	release_sock(sk);

}

EXPORT_SYMBOL(sock_set_sndtimeo);
@@ -1721,12 +1723,14 @@ int sk_getsockopt(struct sock *sk, int level, int optname, 


	case SO_RCVTIMEO_OLD:

	case SO_RCVTIMEO_NEW:

		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);

		lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v,

				      SO_RCVTIMEO_OLD == optname);

		break;



	case SO_SNDTIMEO_OLD:

	case SO_SNDTIMEO_NEW:

		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);

		lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v,

				      SO_SNDTIMEO_OLD == optname);

		break;



	case SO_RCVLOWAT:

net/sched/em_meta.c

+2 −2
Original line number Diff line number Diff line
@@ -568,7 +568,7 @@ META_COLLECTOR(int_sk_rcvtimeo) 
		*err = -1;

		return;

	}

	dst->value = sk->sk_rcvtimeo / HZ;

	dst->value = READ_ONCE(sk->sk_rcvtimeo) / HZ;

}



META_COLLECTOR(int_sk_sndtimeo)
@@ -579,7 +579,7 @@ META_COLLECTOR(int_sk_sndtimeo) 
		*err = -1;

		return;

	}

	dst->value = sk->sk_sndtimeo / HZ;

	dst->value = READ_ONCE(sk->sk_sndtimeo) / HZ;

}



META_COLLECTOR(int_sk_sendmsg_off)