net: annotate sk->sk_err write from do_recvmmsg()
[ Upstream commit e05a5f510f26607616fecdd4ac136310c8bea56b ]
do_recvmmsg() can write to sk->sk_err from multiple threads.
As said before, many other points reading or writing sk_err
need annotations.
Fixes: 34b88a68f26a ("net: Fix use after free in the recvmmsg exit path")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
diff --git a/net/socket.c b/net/socket.c
index 73666b8..5c49074 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -2820,7 +2820,7 @@ static int do_recvmmsg(int fd, struct mmsghdr __user *mmsg,
* error to return on the next call or if the
* app asks about it using getsockopt(SO_ERROR).
*/
- sock->sk->sk_err = -err;
+ WRITE_ONCE(sock->sk->sk_err, -err);
}
out_put:
fput_light(sock->file, fput_needed);