selinux: fix broken peer recv check

Fix a broken networking check. Return an error if peer recv fails.  If
secmark is active and the packet recv succeeds the peer recv error is
ignored.

Signed-off-by: Chad Hanson <chanson@trustedcs.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index a98228e..bf0537d 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -4338,8 +4338,10 @@
 		}
 		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
 				   PEER__RECV, &ad);
-		if (err)
+		if (err) {
 			selinux_netlbl_err(skb, err, 0);
+			return err;
+		}
 	}
 
 	if (secmark_active) {