af_unix: Fix a data-race in unix_dgram_peer_wake_me().

unix_dgram_poll() calls unix_dgram_peer_wake_me() without `other`'s
lock held and check if its receive queue is full.  Here we need to
use unix_recvq_full_lockless() instead of unix_recvq_full(), otherwise
KCSAN will report a data-race.

Fixes: 7d267278a9 ("unix: avoid use-after-free in ep_remove_wait_queue")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20220605232325.11804-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This commit is contained in:
Kuniyuki Iwashima 2022-06-05 16:23:25 -07:00 committed by Paolo Abeni
parent 5e74a4b3ec
commit 662a80946c

View File

@ -490,7 +490,7 @@ static int unix_dgram_peer_wake_me(struct sock *sk, struct sock *other)
* -ECONNREFUSED. Otherwise, if we haven't queued any skbs * -ECONNREFUSED. Otherwise, if we haven't queued any skbs
* to other and its full, we will hang waiting for POLLOUT. * to other and its full, we will hang waiting for POLLOUT.
*/ */
if (unix_recvq_full(other) && !sock_flag(other, SOCK_DEAD)) if (unix_recvq_full_lockless(other) && !sock_flag(other, SOCK_DEAD))
return 1; return 1;
if (connected) if (connected)