netfilter: xtables: change matches to return error code

The following semantic patch does part of the transformation:
// <smpl>
@ rule1 @
struct xt_match ops;
identifier check;
@@
 ops.checkentry = check;

@@
identifier rule1.check;
@@
 check(...) { <...
-return true;
+return 0;
 ...> }

@@
identifier rule1.check;
@@
 check(...) { <...
-return false;
+return -EINVAL;
 ...> }
// </smpl>

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
diff --git a/net/netfilter/xt_tcpudp.c b/net/netfilter/xt_tcpudp.c
index 0072841..efa2ede 100644
--- a/net/netfilter/xt_tcpudp.c
+++ b/net/netfilter/xt_tcpudp.c
@@ -125,7 +125,7 @@
 	const struct xt_tcp *tcpinfo = par->matchinfo;
 
 	/* Must specify no unknown invflags */
-	return !(tcpinfo->invflags & ~XT_TCP_INV_MASK);
+	return (tcpinfo->invflags & ~XT_TCP_INV_MASK) ? -EINVAL : 0;
 }
 
 static bool udp_mt(const struct sk_buff *skb, const struct xt_match_param *par)
@@ -160,7 +160,7 @@
 	const struct xt_udp *udpinfo = par->matchinfo;
 
 	/* Must specify no unknown invflags */
-	return !(udpinfo->invflags & ~XT_UDP_INV_MASK);
+	return (udpinfo->invflags & ~XT_UDP_INV_MASK) ? -EINVAL : 0;
 }
 
 static struct xt_match tcpudp_mt_reg[] __read_mostly = {