netfilter: ipset: Check CIDR value only when attribute is given

There is no reason to check CIDR value regardless attribute
specifying CIDR is given.

Initialize cidr array in element structure on element structure
declaration to let more freedom to the compiler to optimize
initialization right before element structure is used.

Remove local variables cidr and cidr2 for netnet and netportnet
hashes as we do not use packed cidr value for such set types and
can store value directly in e.cidr[].

Signed-off-by: Sergey Popovich <popovich_sergei@mail.ua>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>

1 files changed, 16 insertions, 21 deletions

diff --git a/kernel/net/netfilter/ipset/ip_set_hash_netnet.c b/kernel/net/netfilter/ipset/ip_set_hash_netnet.c
index 60faa3a..f86f6e5 100644
--- a/kernel/net/netfilter/ipset/ip_set_hash_netnet.c
+++ b/kernel/net/netfilter/ipset/ip_set_hash_netnet.c
@@ -160,17 +160,15 @@ hash_netnet4_uadt(struct ip_set *set, struct nlattr *tb[],
 {
 	const struct hash_netnet *h = set->data;
 	ipset_adtfn adtfn = set->variant->adt[adt];
-	struct hash_netnet4_elem e = { };
+	struct hash_netnet4_elem e = { .cidr = { HOST_MASK, HOST_MASK, }, };
 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
 	u32 ip = 0, ip_to = 0, last;
 	u32 ip2 = 0, ip2_from = 0, ip2_to = 0, last2;
-	u8 cidr, cidr2;
 	int ret;
 
 	if (tb[IPSET_ATTR_LINENO])
 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
 
-	e.cidr[0] = e.cidr[1] = HOST_MASK;
 	if (unlikely(!tb[IPSET_ATTR_IP] || !tb[IPSET_ATTR_IP2] ||
 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
 		return -IPSET_ERR_PROTOCOL;
@@ -188,17 +186,15 @@ hash_netnet4_uadt(struct ip_set *set, struct nlattr *tb[],
 		return ret;
 
 	if (tb[IPSET_ATTR_CIDR]) {
-		cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
-		if (!cidr || cidr > HOST_MASK)
+		e.cidr[0] = nla_get_u8(tb[IPSET_ATTR_CIDR]);
+		if (!e.cidr[0] || e.cidr[0] > HOST_MASK)
 			return -IPSET_ERR_INVALID_CIDR;
-		e.cidr[0] = cidr;
 	}
 
 	if (tb[IPSET_ATTR_CIDR2]) {
-		cidr2 = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
-		if (!cidr2 || cidr2 > HOST_MASK)
+		e.cidr[1] = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
+		if (!e.cidr[1] || e.cidr[1] > HOST_MASK)
 			return -IPSET_ERR_INVALID_CIDR;
-		e.cidr[1] = cidr2;
 	}
 
 	if (tb[IPSET_ATTR_CADT_FLAGS]) {
@@ -248,15 +244,13 @@ hash_netnet4_uadt(struct ip_set *set, struct nlattr *tb[],
 
 	while (!after(ip, ip_to)) {
 		e.ip[0] = htonl(ip);
-		last = ip_set_range_to_cidr(ip, ip_to, &cidr);
-		e.cidr[0] = cidr;
+		last = ip_set_range_to_cidr(ip, ip_to, &e.cidr[0]);
 		ip2 = (retried &&
 		       ip == ntohl(h->next.ip[0])) ? ntohl(h->next.ip[1])
 						   : ip2_from;
 		while (!after(ip2, ip2_to)) {
 			e.ip[1] = htonl(ip2);
-			last2 = ip_set_range_to_cidr(ip2, ip2_to, &cidr2);
-			e.cidr[1] = cidr2;
+			last2 = ip_set_range_to_cidr(ip2, ip2_to, &e.cidr[1]);
 			ret = adtfn(set, &e, &ext, &ext, flags);
 			if (ret && !ip_set_eexist(ret, flags))
 				return ret;
@@ -391,14 +385,13 @@ hash_netnet6_uadt(struct ip_set *set, struct nlattr *tb[],
 		  enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
 {
 	ipset_adtfn adtfn = set->variant->adt[adt];
-	struct hash_netnet6_elem e = { };
+	struct hash_netnet6_elem e = { .cidr = { HOST_MASK, HOST_MASK, }, };
 	struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
 	int ret;
 
 	if (tb[IPSET_ATTR_LINENO])
 		*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
 
-	e.cidr[0] = e.cidr[1] = HOST_MASK;
 	if (unlikely(!tb[IPSET_ATTR_IP] || !tb[IPSET_ATTR_IP2] ||
 		     !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
 		return -IPSET_ERR_PROTOCOL;
@@ -417,15 +410,17 @@ hash_netnet6_uadt(struct ip_set *set, struct nlattr *tb[],
 	if (ret)
 		return ret;
 
-	if (tb[IPSET_ATTR_CIDR])
+	if (tb[IPSET_ATTR_CIDR]) {
 		e.cidr[0] = nla_get_u8(tb[IPSET_ATTR_CIDR]);
+		if (!e.cidr[0] || e.cidr[0] > HOST_MASK)
+			return -IPSET_ERR_INVALID_CIDR;
+	}
 
-	if (tb[IPSET_ATTR_CIDR2])
+	if (tb[IPSET_ATTR_CIDR2]) {
 		e.cidr[1] = nla_get_u8(tb[IPSET_ATTR_CIDR2]);
-
-	if (!e.cidr[0] || e.cidr[0] > HOST_MASK || !e.cidr[1] ||
-	    e.cidr[1] > HOST_MASK)
-		return -IPSET_ERR_INVALID_CIDR;
+		if (!e.cidr[1] || e.cidr[1] > HOST_MASK)
+			return -IPSET_ERR_INVALID_CIDR;
+	}
 
 	ip6_netmask(&e.ip[0], e.cidr[0]);
 	ip6_netmask(&e.ip[1], e.cidr[1]);