netfilter: xtables: change targets to return error code

Part of the transition of done by this semantic patch:
// <smpl>
@ rule1 @
struct xt_target 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>

net/ipv4/netfilter/ipt_CLUSTERIP.c

@@ -358,13 +358,13 @@ static int clusterip_tg_check(const struct xt_tgchk_param *par)
 	    cipinfo->hash_mode != CLUSTERIP_HASHMODE_SIP_SPT &&
 	    cipinfo->hash_mode != CLUSTERIP_HASHMODE_SIP_SPT_DPT) {
 		pr_info("unknown mode %u\n", cipinfo->hash_mode);
-		return false;
+		return -EINVAL;
 
 	}
 	if (e->ip.dmsk.s_addr != htonl(0xffffffff) ||
 	    e->ip.dst.s_addr == 0) {
 		pr_info("Please specify destination IP\n");
-		return false;
+		return -EINVAL;
 	}
 
 	/* FIXME: further sanity checks */
@@ -374,20 +374,20 @@ static int clusterip_tg_check(const struct xt_tgchk_param *par)
 		if (!(cipinfo->flags & CLUSTERIP_FLAG_NEW)) {
 			pr_info("no config found for %pI4, need 'new'\n",
 				&e->ip.dst.s_addr);
-			return false;
+			return -EINVAL;
 		} else {
 			struct net_device *dev;
 
 			if (e->ip.iniface[0] == '\0') {
 				pr_info("Please specify an interface name\n");
-				return false;
+				return -EINVAL;
 			}
 
 			dev = dev_get_by_name(&init_net, e->ip.iniface);
 			if (!dev) {
 				pr_info("no such interface %s\n",
 					e->ip.iniface);
-				return false;
+				return -EINVAL;
 			}
 
 			config = clusterip_config_init(cipinfo,
@@ -395,7 +395,7 @@ static int clusterip_tg_check(const struct xt_tgchk_param *par)
 			if (!config) {
 				pr_info("cannot allocate config\n");
 				dev_put(dev);
-				return false;
+				return -EINVAL;
 			}
 			dev_mc_add(config->dev,config->clustermac, ETH_ALEN, 0);
 		}
@@ -405,10 +405,10 @@ static int clusterip_tg_check(const struct xt_tgchk_param *par)
 	if (nf_ct_l3proto_try_module_get(par->family) < 0) {
 		pr_info("cannot load conntrack support for proto=%u\n",
 			par->family);
-		return false;
+		return -EINVAL;
 	}
 
-	return true;
+	return 0;
 }
 
 /* drop reference count of cluster config when rule is deleted */

net/ipv4/netfilter/ipt_ECN.c

@@ -100,18 +100,18 @@ static int ecn_tg_check(const struct xt_tgchk_param *par)
 
 	if (einfo->operation & IPT_ECN_OP_MASK) {
 		pr_info("unsupported ECN operation %x\n", einfo->operation);
-		return false;
+		return -EINVAL;
 	}
 	if (einfo->ip_ect & ~IPT_ECN_IP_MASK) {
 		pr_info("new ECT codepoint %x out of mask\n", einfo->ip_ect);
-		return false;
+		return -EINVAL;
 	}
 	if ((einfo->operation & (IPT_ECN_OP_SET_ECE|IPT_ECN_OP_SET_CWR)) &&
 	    (e->ip.proto != IPPROTO_TCP || (e->ip.invflags & XT_INV_PROTO))) {
 		pr_info("cannot use TCP operations on a non-tcp rule\n");
-		return false;
+		return -EINVAL;
 	}
-	return true;
+	return 0;
 }
 
 static struct xt_target ecn_tg_reg __read_mostly = {

net/ipv4/netfilter/ipt_LOG.c

@@ -445,13 +445,13 @@ static int log_tg_check(const struct xt_tgchk_param *par)
 
 	if (loginfo->level >= 8) {
 		pr_debug("level %u >= 8\n", loginfo->level);
-		return false;
+		return -EINVAL;
 	}
 	if (loginfo->prefix[sizeof(loginfo->prefix)-1] != '\0') {
 		pr_debug("prefix is not null-terminated\n");
-		return false;
+		return -EINVAL;
 	}
-	return true;
+	return 0;
 }
 
 static struct xt_target log_tg_reg __read_mostly = {

net/ipv4/netfilter/ipt_MASQUERADE.c

@@ -34,13 +34,13 @@ static int masquerade_tg_check(const struct xt_tgchk_param *par)
 
 	if (mr->range[0].flags & IP_NAT_RANGE_MAP_IPS) {
 		pr_debug("bad MAP_IPS.\n");
-		return false;
+		return -EINVAL;
 	}
 	if (mr->rangesize != 1) {
 		pr_debug("bad rangesize %u\n", mr->rangesize);
-		return false;
+		return -EINVAL;
 	}
-	return true;
+	return 0;
 }
 
 static unsigned int

net/ipv4/netfilter/ipt_NETMAP.c

@@ -28,13 +28,13 @@ static int netmap_tg_check(const struct xt_tgchk_param *par)
 
 	if (!(mr->range[0].flags & IP_NAT_RANGE_MAP_IPS)) {
 		pr_debug("bad MAP_IPS.\n");
-		return false;
+		return -EINVAL;
 	}
 	if (mr->rangesize != 1) {
 		pr_debug("bad rangesize %u.\n", mr->rangesize);
-		return false;
+		return -EINVAL;
 	}
-	return true;
+	return 0;
 }
 
 static unsigned int

net/ipv4/netfilter/ipt_REDIRECT.c

@@ -32,13 +32,13 @@ static int redirect_tg_check(const struct xt_tgchk_param *par)
 
 	if (mr->range[0].flags & IP_NAT_RANGE_MAP_IPS) {
 		pr_debug("bad MAP_IPS.\n");
-		return false;
+		return -EINVAL;
 	}
 	if (mr->rangesize != 1) {
 		pr_debug("bad rangesize %u.\n", mr->rangesize);
-		return false;
+		return -EINVAL;
 	}
-	return true;
+	return 0;
 }
 
 static unsigned int

net/ipv4/netfilter/ipt_REJECT.c

@@ -181,16 +181,16 @@ static int reject_tg_check(const struct xt_tgchk_param *par)
 
 	if (rejinfo->with == IPT_ICMP_ECHOREPLY) {
 		pr_info("ECHOREPLY no longer supported.\n");
-		return false;
+		return -EINVAL;
 	} else if (rejinfo->with == IPT_TCP_RESET) {
 		/* Must specify that it's a TCP packet */
 		if (e->ip.proto != IPPROTO_TCP ||
 		    (e->ip.invflags & XT_INV_PROTO)) {
 			pr_info("TCP_RESET invalid for non-tcp\n");
-			return false;
+			return -EINVAL;
 		}
 	}
-	return true;
+	return 0;
 }
 
 static struct xt_target reject_tg_reg __read_mostly = {

net/ipv4/netfilter/ipt_ULOG.c

@@ -313,14 +313,14 @@ static int ulog_tg_check(const struct xt_tgchk_param *par)
 
 	if (loginfo->prefix[sizeof(loginfo->prefix) - 1] != '\0') {
 		pr_debug("prefix not null-terminated\n");
-		return false;
+		return -EINVAL;
 	}
 	if (loginfo->qthreshold > ULOG_MAX_QLEN) {
 		pr_debug("queue threshold %Zu > MAX_QLEN\n",
 			 loginfo->qthreshold);
-		return false;
+		return -EINVAL;
 	}
-	return true;
+	return 0;
 }
 
 #ifdef CONFIG_COMPAT

net/ipv4/netfilter/nf_nat_rule.c

@@ -81,9 +81,9 @@ static int ipt_snat_checkentry(const struct xt_tgchk_param *par)
 	/* Must be a valid range */
 	if (mr->rangesize != 1) {
 		pr_info("SNAT: multiple ranges no longer supported\n");
-		return false;
+		return -EINVAL;
 	}
-	return true;
+	return 0;
 }
 
 static int ipt_dnat_checkentry(const struct xt_tgchk_param *par)
@@ -93,9 +93,9 @@ static int ipt_dnat_checkentry(const struct xt_tgchk_param *par)
 	/* Must be a valid range */
 	if (mr->rangesize != 1) {
 		pr_info("DNAT: multiple ranges no longer supported\n");
-		return false;
+		return -EINVAL;
 	}
-	return true;
+	return 0;
 }
 
 unsigned int