Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for your net tree,
they are:

1) Fix use after free of struct proc_dir_entry in ipt_CLUSTERIP, patch
   from Sabrina Dubroca.

2) Fix spurious EINVAL errors from iptables over nft compatibility layer.

3) Reload pointer to ip header only if there is non-terminal verdict,
   ie. XT_CONTINUE, otherwise invalid memory access may happen, patch
   from Taehee Yoo.

4) Fix interaction between SYNPROXY and NAT, SYNPROXY adds sequence
   adjustment already, however from nf_nat_setup() assumes there's not.
   Patch from Xin Long.

5) Fix burst arithmetics in nft_limit as Joe Stringer mentioned during
   NFWS in Faro. Patch from Andy Zhou.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/netfilter/arp_tables.c

@@ -268,14 +268,14 @@ unsigned int arpt_do_table(struct sk_buff *skb,
 		acpar.targinfo = t->data;
 		verdict = t->u.kernel.target->target(skb, &acpar);
 
-		/* Target might have changed stuff. */
-		arp = arp_hdr(skb);
-
-		if (verdict == XT_CONTINUE)
+		if (verdict == XT_CONTINUE) {
+			/* Target might have changed stuff. */
+			arp = arp_hdr(skb);
 			e = arpt_next_entry(e);
-		else
+		} else {
 			/* Verdict */
 			break;
+		}
 	} while (!acpar.hotdrop);
 	xt_write_recseq_end(addend);
 	local_bh_enable();

net/ipv4/netfilter/ip_tables.c

@@ -352,13 +352,14 @@ ipt_do_table(struct sk_buff *skb,
 		acpar.targinfo = t->data;
 
 		verdict = t->u.kernel.target->target(skb, &acpar);
-		/* Target might have changed stuff. */
-		ip = ip_hdr(skb);
-		if (verdict == XT_CONTINUE)
+		if (verdict == XT_CONTINUE) {
+			/* Target might have changed stuff. */
+			ip = ip_hdr(skb);
 			e = ipt_next_entry(e);
-		else
+		} else {
 			/* Verdict */
 			break;
+		}
 	} while (!acpar.hotdrop);
 
 	xt_write_recseq_end(addend);

net/ipv4/netfilter/ipt_CLUSTERIP.c

@@ -117,7 +117,8 @@ clusterip_config_entry_put(struct net *net, struct clusterip_config *c)
 		 * functions are also incrementing the refcount on their own,
 		 * so it's safe to remove the entry even if it's in use. */
 #ifdef CONFIG_PROC_FS
-		proc_remove(c->pde);
+		if (cn->procdir)
+			proc_remove(c->pde);
 #endif
 		return;
 	}
@@ -815,6 +816,7 @@ static void clusterip_net_exit(struct net *net)
 #ifdef CONFIG_PROC_FS
 	struct clusterip_net *cn = net_generic(net, clusterip_net_id);
 	proc_remove(cn->procdir);
+	cn->procdir = NULL;
 #endif
 	nf_unregister_net_hook(net, &cip_arp_ops);
 }

net/netfilter/nf_nat_core.c

@@ -441,7 +441,7 @@ nf_nat_setup_info(struct nf_conn *ct,
 		else
 			ct->status |= IPS_DST_NAT;
 
-		if (nfct_help(ct))
+		if (nfct_help(ct) && !nfct_seqadj(ct))
 			if (!nfct_seqadj_ext_add(ct))
 				return NF_DROP;
 	}

net/netfilter/nft_compat.c

@@ -305,7 +305,7 @@ static int nft_target_validate(const struct nft_ctx *ctx,
 		const struct nf_hook_ops *ops = &basechain->ops[0];
 
 		hook_mask = 1 << ops->hooknum;
-		if (!(hook_mask & target->hooks))
+		if (target->hooks && !(hook_mask & target->hooks))
 			return -EINVAL;
 
 		ret = nft_compat_chain_validate_dependency(target->table,
@@ -484,7 +484,7 @@ static int nft_match_validate(const struct nft_ctx *ctx,
 		const struct nf_hook_ops *ops = &basechain->ops[0];
 
 		hook_mask = 1 << ops->hooknum;
-		if (!(hook_mask & match->hooks))
+		if (match->hooks && !(hook_mask & match->hooks))
 			return -EINVAL;
 
 		ret = nft_compat_chain_validate_dependency(match->table,

net/netfilter/nft_limit.c

@@ -65,19 +65,23 @@ static int nft_limit_init(struct nft_limit *limit,
 	limit->nsecs = unit * NSEC_PER_SEC;
 	if (limit->rate == 0 || limit->nsecs < unit)
 		return -EOVERFLOW;
-	limit->tokens = limit->tokens_max = limit->nsecs;
-
-	if (tb[NFTA_LIMIT_BURST]) {
-		u64 rate;
 
+	if (tb[NFTA_LIMIT_BURST])
 		limit->burst = ntohl(nla_get_be32(tb[NFTA_LIMIT_BURST]));
+	else
+		limit->burst = 0;
+
+	if (limit->rate + limit->burst < limit->rate)
+		return -EOVERFLOW;
 
-		rate = limit->rate + limit->burst;
-		if (rate < limit->rate)
-			return -EOVERFLOW;
+	/* The token bucket size limits the number of tokens can be
+	 * accumulated. tokens_max specifies the bucket size.
+	 * tokens_max = unit * (rate + burst) / rate.
+	 */
+	limit->tokens = div_u64(limit->nsecs * (limit->rate + limit->burst),
+				limit->rate);
+	limit->tokens_max = limit->tokens;
 
-		limit->rate = rate;
-	}
 	if (tb[NFTA_LIMIT_FLAGS]) {
 		u32 flags = ntohl(nla_get_be32(tb[NFTA_LIMIT_FLAGS]));
 
@@ -95,9 +99,8 @@ static int nft_limit_dump(struct sk_buff *skb, const struct nft_limit *limit,
 {
 	u32 flags = limit->invert ? NFT_LIMIT_F_INV : 0;
 	u64 secs = div_u64(limit->nsecs, NSEC_PER_SEC);
-	u64 rate = limit->rate - limit->burst;
 
-	if (nla_put_be64(skb, NFTA_LIMIT_RATE, cpu_to_be64(rate),
+	if (nla_put_be64(skb, NFTA_LIMIT_RATE, cpu_to_be64(limit->rate),
 			 NFTA_LIMIT_PAD) ||
 	    nla_put_be64(skb, NFTA_LIMIT_UNIT, cpu_to_be64(secs),
 			 NFTA_LIMIT_PAD) ||