inet_diag: bc: read cgroup id only for full sockets

Fix bug introduced by commit b1f3e43 ("inet_diag: add support for
cgroup filter").

Signed-off-by: Dmitry Yakunin <[email protected]>
Reported-by: [email protected]
Reported-by: [email protected]
Fixes: b1f3e43 ("inet_diag: add support for cgroup filter")
Signed-off-by: David S. Miller <[email protected]>

Author: zeil

net/ipv4/inet_diag.c

@@ -746,7 +746,8 @@ int inet_diag_bc_sk(const struct nlattr *bc, struct sock *sk)
 	else
 		entry.mark = 0;
 #ifdef CONFIG_SOCK_CGROUP_DATA
-	entry.cgroup_id = cgroup_id(sock_cgroup_ptr(&sk->sk_cgrp_data));
+	entry.cgroup_id = sk_fullsock(sk) ?
+		cgroup_id(sock_cgroup_ptr(&sk->sk_cgrp_data)) : 0;
 #endif
 
 	return inet_diag_bc_run(bc, &entry);