af_unix: Annotate data-race of net->unx.sysctl_max_dgram_qlen.

net->unx.sysctl_max_dgram_qlen is exposed as a sysctl knob and can be
changed concurrently.

Let's use READ_ONCE() in unix_create1().

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index de2a5e334a88eb11235d4308142f63508795d728..623ee39657e2350bdd1a5fd1694820f7d5c04df3 100644 (file)
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -976,7 +976,7 @@ static struct sock *unix_create1(struct net *net, struct socket *sock, int kern,
        sk->sk_hash             = unix_unbound_hash(sk);
        sk->sk_allocation       = GFP_KERNEL_ACCOUNT;
        sk->sk_write_space      = unix_write_space;
-       sk->sk_max_ack_backlog  = net->unx.sysctl_max_dgram_qlen;
+       sk->sk_max_ack_backlog  = READ_ONCE(net->unx.sysctl_max_dgram_qlen);
        sk->sk_destruct         = unix_sock_destructor;
        u = unix_sk(sk);
        u->listener = NULL;