[NETFILTER]: Export ip6_masked_addrcmp, don't pass IPv6 addresses on stack

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/netfilter_ipv6/ip6_tables.h

@@ -476,6 +476,10 @@ extern int ip6t_ext_hdr(u8 nexthdr);
 extern int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset,
 			 int target, unsigned short *fragoff);
 
+extern int ip6_masked_addrcmp(const struct in6_addr *addr1,
+			      const struct in6_addr *mask,
+			      const struct in6_addr *addr2);
+
 #define IP6T_ALIGN(s) (((s) + (__alignof__(struct ip6t_entry)-1)) & ~(__alignof__(struct ip6t_entry)-1))
 
 #endif /*__KERNEL__*/

net/ipv6/netfilter/ip6_tables.c

@@ -119,13 +119,14 @@ static LIST_HEAD(ip6t_tables);
 #define up(x) do { printk("UP:%u:" #x "\n", __LINE__); up(x); } while(0)
 #endif
 
-static int ip6_masked_addrcmp(struct in6_addr addr1, struct in6_addr mask,
-			      struct in6_addr addr2)
+int
+ip6_masked_addrcmp(const struct in6_addr *addr1, const struct in6_addr *mask,
+                   const struct in6_addr *addr2)
 {
 	int i;
 	for( i = 0; i < 16; i++){
-		if((addr1.s6_addr[i] & mask.s6_addr[i]) != 
-		   (addr2.s6_addr[i] & mask.s6_addr[i]))
+		if((addr1->s6_addr[i] & mask->s6_addr[i]) != 
+		   (addr2->s6_addr[i] & mask->s6_addr[i]))
 			return 1;
 	}
 	return 0;
@@ -159,10 +160,10 @@ ip6_packet_match(const struct sk_buff *skb,
 
 #define FWINV(bool,invflg) ((bool) ^ !!(ip6info->invflags & invflg))
 
-	if (FWINV(ip6_masked_addrcmp(ipv6->saddr,ip6info->smsk,ip6info->src),
-		  IP6T_INV_SRCIP)
-	    || FWINV(ip6_masked_addrcmp(ipv6->daddr,ip6info->dmsk,ip6info->dst),
-		     IP6T_INV_DSTIP)) {
+	if (FWINV(ip6_masked_addrcmp(&ipv6->saddr, &ip6info->smsk,
+	                             &ip6info->src), IP6T_INV_SRCIP)
+	    || FWINV(ip6_masked_addrcmp(&ipv6->daddr, &ip6info->dmsk,
+	                                &ip6info->dst), IP6T_INV_DSTIP)) {
 		dprintf("Source or dest mismatch.\n");
 /*
 		dprintf("SRC: %u. Mask: %u. Target: %u.%s\n", ip->saddr,
@@ -2131,6 +2132,7 @@ EXPORT_SYMBOL(ip6t_register_target);
 EXPORT_SYMBOL(ip6t_unregister_target);
 EXPORT_SYMBOL(ip6t_ext_hdr);
 EXPORT_SYMBOL(ipv6_find_hdr);
+EXPORT_SYMBOL(ip6_masked_addrcmp);
 
 module_init(init);
 module_exit(fini);