Commit 0bb4d124 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net: annotate data-races around sk->sk_tx_queue_mapping 



This field can be read or written without socket lock being held.

Add annotations to avoid load-store tearing.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5eef0b8d

include/net/sock.h

+16 −4
Original line number Diff line number Diff line
@@ -2007,21 +2007,33 @@ static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) 
	/* sk_tx_queue_mapping accept only upto a 16-bit value */

	if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))

		return;

	sk->sk_tx_queue_mapping = tx_queue;

	/* Paired with READ_ONCE() in sk_tx_queue_get() and

	 * other WRITE_ONCE() because socket lock might be not held.

	 */

	WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue);

}



#define NO_QUEUE_MAPPING	USHRT_MAX



static inline void sk_tx_queue_clear(struct sock *sk)

{

	sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING;

	/* Paired with READ_ONCE() in sk_tx_queue_get() and

	 * other WRITE_ONCE() because socket lock might be not held.

	 */

	WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING);

}



static inline int sk_tx_queue_get(const struct sock *sk)

{

	if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING)

		return sk->sk_tx_queue_mapping;

	if (sk) {

		/* Paired with WRITE_ONCE() in sk_tx_queue_clear()

		 * and sk_tx_queue_set().

		 */

		int val = READ_ONCE(sk->sk_tx_queue_mapping);



		if (val != NO_QUEUE_MAPPING)

			return val;

	}

	return -1;

}