net: annotate data-race around sk->sk_txrehash

[ Upstream commit c76a032889 ]

sk_getsockopt() runs locklessly. This means sk->sk_txrehash
can be read while other threads are changing its value.

Other locations were handled in commit cb6cd2cec7
("tcp: Change SYN ACK retransmit behaviour to account for rehash")

Fixes: 26859240e4 ("txhash: Add socket option to control TX hash rethink behavior")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Akhmat Karakotov <hmukos@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Eric Dumazet 2023-07-28 15:03:09 +00:00 committed by Greg Kroah-Hartman
parent 6269d3eaf4
commit d0e273bc55

View file

@ -1523,7 +1523,9 @@ int sk_setsockopt(struct sock *sk, int level, int optname,
}
if ((u8)val == SOCK_TXREHASH_DEFAULT)
val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
/* Paired with READ_ONCE() in tcp_rtx_synack() */
/* Paired with READ_ONCE() in tcp_rtx_synack()
* and sk_getsockopt().
*/
WRITE_ONCE(sk->sk_txrehash, (u8)val);
break;
@ -1930,7 +1932,8 @@ int sk_getsockopt(struct sock *sk, int level, int optname,
break;
case SO_TXREHASH:
v.val = sk->sk_txrehash;
/* Paired with WRITE_ONCE() in sk_setsockopt() */
v.val = READ_ONCE(sk->sk_txrehash);
break;
default: