Merge branch 'master' of git://1984.lsi.us.es/nf

Pablo Neira Ayuso says:

====================
The following patchset contains Netfilter/IPVS fixes for 3.8-rc7, they are:

* Fix oops in IPVS state-sync due to releasing a random memory area due
  to unitialized pointer, from Dan Carpenter.

* Fix SCTP flow establishment due to bad checksumming mangling in IPVS,
  from Daniel Borkmann.

* Three fixes for the recently added IPv6 NPT, all from YOSHIFUJI Hideaki,
  with an amendment collapsed into those patches from Ulrich Weber. They
  fiix adjustment calculation, fix prefix mangling and ensure LSB of
  prefixes are zeroes (as required by RFC).

Specifically, it took me a while to validate the 1's complement arithmetics/
checksumming approach in the IPv6 NPT code.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 33 insertions, 22 deletions

diff --git a/net/ipv6/netfilter/ip6t_NPT.c b/net/ipv6/netfilter/ip6t_NPT.c
index 7302b0b7b642..83acc1405a18 100644
--- a/net/ipv6/netfilter/ip6t_NPT.c
+++ b/net/ipv6/netfilter/ip6t_NPT.c
@@ -9,6 +9,7 @@
 #include <linux/module.h>
 #include <linux/skbuff.h>
 #include <linux/ipv6.h>
+#include <net/ipv6.h>
 #include <linux/netfilter.h>
 #include <linux/netfilter_ipv6.h>
 #include <linux/netfilter_ipv6/ip6t_NPT.h>
@@ -18,11 +19,20 @@ static int ip6t_npt_checkentry(const struct xt_tgchk_param *par)
 {
 	struct ip6t_npt_tginfo *npt = par->targinfo;
 	__wsum src_sum = 0, dst_sum = 0;
+	struct in6_addr pfx;
 	unsigned int i;
 
 	if (npt->src_pfx_len > 64 || npt->dst_pfx_len > 64)
 		return -EINVAL;
 
+	/* Ensure that LSB of prefix is zero */
+	ipv6_addr_prefix(&pfx, &npt->src_pfx.in6, npt->src_pfx_len);
+	if (!ipv6_addr_equal(&pfx, &npt->src_pfx.in6))
+		return -EINVAL;
+	ipv6_addr_prefix(&pfx, &npt->dst_pfx.in6, npt->dst_pfx_len);
+	if (!ipv6_addr_equal(&pfx, &npt->dst_pfx.in6))
+		return -EINVAL;
+
 	for (i = 0; i < ARRAY_SIZE(npt->src_pfx.in6.s6_addr16); i++) {
 		src_sum = csum_add(src_sum,
 				(__force __wsum)npt->src_pfx.in6.s6_addr16[i]);
@@ -30,7 +40,7 @@ static int ip6t_npt_checkentry(const struct xt_tgchk_param *par)
 				(__force __wsum)npt->dst_pfx.in6.s6_addr16[i]);
 	}
 
-	npt->adjustment = (__force __sum16) csum_sub(src_sum, dst_sum);
+	npt->adjustment = ~csum_fold(csum_sub(src_sum, dst_sum));
 	return 0;
 }
 
@@ -51,7 +61,7 @@ static bool ip6t_npt_map_pfx(const struct ip6t_npt_tginfo *npt,
 
 		idx = i / 32;
 		addr->s6_addr32[idx] &= mask;
-		addr->s6_addr32[idx] |= npt->dst_pfx.in6.s6_addr32[idx];
+		addr->s6_addr32[idx] |= ~mask & npt->dst_pfx.in6.s6_addr32[idx];
 	}
 
 	if (pfx_len <= 48)
@@ -66,8 +76,8 @@ static bool ip6t_npt_map_pfx(const struct ip6t_npt_tginfo *npt,
 			return false;
 	}
 
-	sum = (__force __sum16) csum_add((__force __wsum)addr->s6_addr16[idx],
-			 npt->adjustment);
+	sum = ~csum_fold(csum_add(csum_unfold((__force __sum16)addr->s6_addr16[idx]),
+				  csum_unfold(npt->adjustment)));
 	if (sum == CSUM_MANGLED_0)
 		sum = 0;
 	*(__force __sum16 *)&addr->s6_addr16[idx] = sum;
diff --git a/net/netfilter/ipvs/ip_vs_proto_sctp.c b/net/netfilter/ipvs/ip_vs_proto_sctp.c
index 746048b13ef3..ae8ec6f27688 100644
--- a/net/netfilter/ipvs/ip_vs_proto_sctp.c
+++ b/net/netfilter/ipvs/ip_vs_proto_sctp.c
@@ -61,14 +61,27 @@ sctp_conn_schedule(int af, struct sk_buff *skb, struct ip_vs_proto_data *pd,
 	return 1;
 }
 
+static void sctp_nat_csum(struct sk_buff *skb, sctp_sctphdr_t *sctph,
+			  unsigned int sctphoff)
+{
+	__u32 crc32;
+	struct sk_buff *iter;
+
+	crc32 = sctp_start_cksum((__u8 *)sctph, skb_headlen(skb) - sctphoff);
+	skb_walk_frags(skb, iter)
+		crc32 = sctp_update_cksum((u8 *) iter->data,
+					  skb_headlen(iter), crc32);
+	sctph->checksum = sctp_end_cksum(crc32);
+
+	skb->ip_summed = CHECKSUM_UNNECESSARY;
+}
+
 static int
 sctp_snat_handler(struct sk_buff *skb, struct ip_vs_protocol *pp,
 		  struct ip_vs_conn *cp, struct ip_vs_iphdr *iph)
 {
 	sctp_sctphdr_t *sctph;
 	unsigned int sctphoff = iph->len;
-	struct sk_buff *iter;
-	__be32 crc32;
 
 #ifdef CONFIG_IP_VS_IPV6
 	if (cp->af == AF_INET6 && iph->fragoffs)
@@ -92,13 +105,7 @@ sctp_snat_handler(struct sk_buff *skb, struct ip_vs_protocol *pp,
 	sctph = (void *) skb_network_header(skb) + sctphoff;
 	sctph->source = cp->vport;
 
-	/* Calculate the checksum */
-	crc32 = sctp_start_cksum((u8 *) sctph, skb_headlen(skb) - sctphoff);
-	skb_walk_frags(skb, iter)
-		crc32 = sctp_update_cksum((u8 *) iter->data, skb_headlen(iter),
-				          crc32);
-	crc32 = sctp_end_cksum(crc32);
-	sctph->checksum = crc32;
+	sctp_nat_csum(skb, sctph, sctphoff);
 
 	return 1;
 }
@@ -109,8 +116,6 @@ sctp_dnat_handler(struct sk_buff *skb, struct ip_vs_protocol *pp,
 {
 	sctp_sctphdr_t *sctph;
 	unsigned int sctphoff = iph->len;
-	struct sk_buff *iter;
-	__be32 crc32;
 
 #ifdef CONFIG_IP_VS_IPV6
 	if (cp->af == AF_INET6 && iph->fragoffs)
@@ -134,13 +139,7 @@ sctp_dnat_handler(struct sk_buff *skb, struct ip_vs_protocol *pp,
 	sctph = (void *) skb_network_header(skb) + sctphoff;
 	sctph->dest = cp->dport;
 
-	/* Calculate the checksum */
-	crc32 = sctp_start_cksum((u8 *) sctph, skb_headlen(skb) - sctphoff);
-	skb_walk_frags(skb, iter)
-		crc32 = sctp_update_cksum((u8 *) iter->data, skb_headlen(iter),
-					  crc32);
-	crc32 = sctp_end_cksum(crc32);
-	sctph->checksum = crc32;
+	sctp_nat_csum(skb, sctph, sctphoff);
 
 	return 1;
 }
diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c
index effa10c9e4e3..44fd10c539ac 100644
--- a/net/netfilter/ipvs/ip_vs_sync.c
+++ b/net/netfilter/ipvs/ip_vs_sync.c
@@ -1795,6 +1795,8 @@ int start_sync_thread(struct net *net, int state, char *mcast_ifn, __u8 syncid)
 					     GFP_KERNEL);
 			if (!tinfo->buf)
 				goto outtinfo;
+		} else {
+			tinfo->buf = NULL;
 		}
 		tinfo->id = id;