net/tcp_ao: Don't leak ao_info on error-path

It seems I introduced it together with TCP_AO_CMDF_AO_REQUIRED, on
version 5 [1] of TCP-AO patches. Quite frustrative that having all these
selftests that I've written, running kmemtest & kcov was always in todo.

[1]: https://lore.kernel.org/netdev/[email protected]/

Reported-by: Jakub Kicinski <[email protected]>
Closes: https://lore.kernel.org/netdev/[email protected]/
Fixes: 0aadc73 ("net/tcp: Prevent TCP-MD5 with TCP-AO being set")
Cc: [email protected]
Signed-off-by: Dmitry Safonov <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: 0x7f454c46

net/ipv4/tcp_ao.c

@@ -1968,8 +1968,10 @@ static int tcp_ao_info_cmd(struct sock *sk, unsigned short int family,
 		first = true;
 	}
 
-	if (cmd.ao_required && tcp_ao_required_verify(sk))
-		return -EKEYREJECTED;
+	if (cmd.ao_required && tcp_ao_required_verify(sk)) {
+		err = -EKEYREJECTED;
+		goto out;
+	}
 
 	/* For sockets in TCP_CLOSED it's possible set keys that aren't
 	 * matching the future peer (address/port/VRF/etc),