Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

Pull networking fixes from David Miller:

 1) Null termination fix in dns_resolver got the pointer dereferncing
    wrong, fix from Ben Hutchings.

 2) ip_options_compile() has a benign but real buffer overflow when
    parsing options.  From Eric Dumazet.

 3) Table updates can crash in netfilter's nftables if none of the state
    flags indicate an actual change, from Pablo Neira Ayuso.

 4) Fix race in nf_tables dumping, also from Pablo.

 5) GRE-GRO support broke the forwarding path because the segmentation
    state was not fully initialized in these paths, from Jerry Chu.

 6) sunvnet driver leaks objects and potentially crashes on module
    unload, from Sowmini Varadhan.

 7) We can accidently generate the same handle for several u32
    classifier filters, fix from Cong Wang.

 8) Several edge case bug fixes in fragment handling in xen-netback,
    from Zoltan Kiss.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (21 commits)
  ipv4: fix buffer overflow in ip_options_compile()
  batman-adv: fix TT VLAN inconsistency on VLAN re-add
  batman-adv: drop QinQ claim frames in bridge loop avoidance
  dns_resolver: Null-terminate the right string
  xen-netback: Fix pointer incrementation to avoid incorrect logging
  xen-netback: Fix releasing header slot on error path
  xen-netback: Fix releasing frag_list skbs in error path
  xen-netback: Fix handling frag_list on grant op error path
  net_sched: avoid generating same handle for u32 filters
  net: huawei_cdc_ncm: add "subclass 3" devices
  net: qmi_wwan: add two Sierra Wireless/Netgear devices
  wan/x25_asy: integer overflow in x25_asy_change_mtu()
  net: ppp: fix creating PPP pass and active filters
  net/mlx4_en: cq->irq_desc wasn't set in legacy EQ's
  sunvnet: clean up objects created in vnet_new() on vnet_exit()
  r8169: Enable RX_MULTI_EN for RTL_GIGA_MAC_VER_40
  net-gre-gro: Fix a bug that breaks the forwarding path
  netfilter: nf_tables: 64bit stats need some extra synchronization
  netfilter: nf_tables: set NLM_F_DUMP_INTR if netlink dumping is stale
  netfilter: nf_tables: safe RCU iteration on list when dumping
  ...

2 files changed, 95 insertions, 55 deletions

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index ab4566cfcbe4..8746ff9a8357 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -35,7 +35,7 @@ int nft_register_afinfo(struct net *net, struct nft_af_info *afi)
 {
 	INIT_LIST_HEAD(&afi->tables);
 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
-	list_add_tail(&afi->list, &net->nft.af_info);
+	list_add_tail_rcu(&afi->list, &net->nft.af_info);
 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
 	return 0;
 }
@@ -51,7 +51,7 @@ EXPORT_SYMBOL_GPL(nft_register_afinfo);
 void nft_unregister_afinfo(struct nft_af_info *afi)
 {
 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
-	list_del(&afi->list);
+	list_del_rcu(&afi->list);
 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
 }
 EXPORT_SYMBOL_GPL(nft_unregister_afinfo);
@@ -277,11 +277,14 @@ static int nf_tables_dump_tables(struct sk_buff *skb,
 	struct net *net = sock_net(skb->sk);
 	int family = nfmsg->nfgen_family;
 
-	list_for_each_entry(afi, &net->nft.af_info, list) {
+	rcu_read_lock();
+	cb->seq = net->nft.base_seq;
+
+	list_for_each_entry_rcu(afi, &net->nft.af_info, list) {
 		if (family != NFPROTO_UNSPEC && family != afi->family)
 			continue;
 
-		list_for_each_entry(table, &afi->tables, list) {
+		list_for_each_entry_rcu(table, &afi->tables, list) {
 			if (idx < s_idx)
 				goto cont;
 			if (idx > s_idx)
@@ -294,11 +297,14 @@ static int nf_tables_dump_tables(struct sk_buff *skb,
 						      NLM_F_MULTI,
 						      afi->family, table) < 0)
 				goto done;
+
+			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
 cont:
 			idx++;
 		}
 	}
 done:
+	rcu_read_unlock();
 	cb->args[0] = idx;
 	return skb->len;
 }
@@ -407,6 +413,9 @@ static int nf_tables_updtable(struct nft_ctx *ctx)
 	if (flags & ~NFT_TABLE_F_DORMANT)
 		return -EINVAL;
 
+	if (flags == ctx->table->flags)
+		return 0;
+
 	trans = nft_trans_alloc(ctx, NFT_MSG_NEWTABLE,
 				sizeof(struct nft_trans_table));
 	if (trans == NULL)
@@ -514,7 +523,7 @@ static int nf_tables_newtable(struct sock *nlsk, struct sk_buff *skb,
 		module_put(afi->owner);
 		return err;
 	}
-	list_add_tail(&table->list, &afi->tables);
+	list_add_tail_rcu(&table->list, &afi->tables);
 	return 0;
 }
 
@@ -546,7 +555,7 @@ static int nf_tables_deltable(struct sock *nlsk, struct sk_buff *skb,
 	if (err < 0)
 		return err;
 
-	list_del(&table->list);
+	list_del_rcu(&table->list);
 	return 0;
 }
 
@@ -635,13 +644,20 @@ static int nft_dump_stats(struct sk_buff *skb, struct nft_stats __percpu *stats)
 {
 	struct nft_stats *cpu_stats, total;
 	struct nlattr *nest;
+	unsigned int seq;
+	u64 pkts, bytes;
 	int cpu;
 
 	memset(&total, 0, sizeof(total));
 	for_each_possible_cpu(cpu) {
 		cpu_stats = per_cpu_ptr(stats, cpu);
-		total.pkts += cpu_stats->pkts;
-		total.bytes += cpu_stats->bytes;
+		do {
+			seq = u64_stats_fetch_begin_irq(&cpu_stats->syncp);
+			pkts = cpu_stats->pkts;
+			bytes = cpu_stats->bytes;
+		} while (u64_stats_fetch_retry_irq(&cpu_stats->syncp, seq));
+		total.pkts += pkts;
+		total.bytes += bytes;
 	}
 	nest = nla_nest_start(skb, NFTA_CHAIN_COUNTERS);
 	if (nest == NULL)
@@ -761,12 +777,15 @@ static int nf_tables_dump_chains(struct sk_buff *skb,
 	struct net *net = sock_net(skb->sk);
 	int family = nfmsg->nfgen_family;
 
-	list_for_each_entry(afi, &net->nft.af_info, list) {
+	rcu_read_lock();
+	cb->seq = net->nft.base_seq;
+
+	list_for_each_entry_rcu(afi, &net->nft.af_info, list) {
 		if (family != NFPROTO_UNSPEC && family != afi->family)
 			continue;
 
-		list_for_each_entry(table, &afi->tables, list) {
-			list_for_each_entry(chain, &table->chains, list) {
+		list_for_each_entry_rcu(table, &afi->tables, list) {
+			list_for_each_entry_rcu(chain, &table->chains, list) {
 				if (idx < s_idx)
 					goto cont;
 				if (idx > s_idx)
@@ -778,17 +797,19 @@ static int nf_tables_dump_chains(struct sk_buff *skb,
 							      NLM_F_MULTI,
 							      afi->family, table, chain) < 0)
 					goto done;
+
+				nl_dump_check_consistent(cb, nlmsg_hdr(skb));
 cont:
 				idx++;
 			}
 		}
 	}
 done:
+	rcu_read_unlock();
 	cb->args[0] = idx;
 	return skb->len;
 }
 
-
 static int nf_tables_getchain(struct sock *nlsk, struct sk_buff *skb,
 			      const struct nlmsghdr *nlh,
 			      const struct nlattr * const nla[])
@@ -861,7 +882,7 @@ static struct nft_stats __percpu *nft_stats_alloc(const struct nlattr *attr)
 	if (!tb[NFTA_COUNTER_BYTES] || !tb[NFTA_COUNTER_PACKETS])
 		return ERR_PTR(-EINVAL);
 
-	newstats = alloc_percpu(struct nft_stats);
+	newstats = netdev_alloc_pcpu_stats(struct nft_stats);
 	if (newstats == NULL)
 		return ERR_PTR(-ENOMEM);
 
@@ -1077,7 +1098,7 @@ static int nf_tables_newchain(struct sock *nlsk, struct sk_buff *skb,
 			}
 			basechain->stats = stats;
 		} else {
-			stats = alloc_percpu(struct nft_stats);
+			stats = netdev_alloc_pcpu_stats(struct nft_stats);
 			if (IS_ERR(stats)) {
 				module_put(type->owner);
 				kfree(basechain);
@@ -1130,7 +1151,7 @@ static int nf_tables_newchain(struct sock *nlsk, struct sk_buff *skb,
 		goto err2;
 
 	table->use++;
-	list_add_tail(&chain->list, &table->chains);
+	list_add_tail_rcu(&chain->list, &table->chains);
 	return 0;
 err2:
 	if (!(table->flags & NFT_TABLE_F_DORMANT) &&
@@ -1180,7 +1201,7 @@ static int nf_tables_delchain(struct sock *nlsk, struct sk_buff *skb,
 		return err;
 
 	table->use--;
-	list_del(&chain->list);
+	list_del_rcu(&chain->list);
 	return 0;
 }
 
@@ -1199,9 +1220,9 @@ int nft_register_expr(struct nft_expr_type *type)
 {
 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
 	if (type->family == NFPROTO_UNSPEC)
-		list_add_tail(&type->list, &nf_tables_expressions);
+		list_add_tail_rcu(&type->list, &nf_tables_expressions);
 	else
-		list_add(&type->list, &nf_tables_expressions);
+		list_add_rcu(&type->list, &nf_tables_expressions);
 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
 	return 0;
 }
@@ -1216,7 +1237,7 @@ EXPORT_SYMBOL_GPL(nft_register_expr);
 void nft_unregister_expr(struct nft_expr_type *type)
 {
 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
-	list_del(&type->list);
+	list_del_rcu(&type->list);
 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
 }
 EXPORT_SYMBOL_GPL(nft_unregister_expr);
@@ -1549,16 +1570,17 @@ static int nf_tables_dump_rules(struct sk_buff *skb,
 	unsigned int idx = 0, s_idx = cb->args[0];
 	struct net *net = sock_net(skb->sk);
 	int family = nfmsg->nfgen_family;
-	u8 genctr = ACCESS_ONCE(net->nft.genctr);
-	u8 gencursor = ACCESS_ONCE(net->nft.gencursor);
 
-	list_for_each_entry(afi, &net->nft.af_info, list) {
+	rcu_read_lock();
+	cb->seq = net->nft.base_seq;
+
+	list_for_each_entry_rcu(afi, &net->nft.af_info, list) {
 		if (family != NFPROTO_UNSPEC && family != afi->family)
 			continue;
 
-		list_for_each_entry(table, &afi->tables, list) {
-			list_for_each_entry(chain, &table->chains, list) {
-				list_for_each_entry(rule, &chain->rules, list) {
+		list_for_each_entry_rcu(table, &afi->tables, list) {
+			list_for_each_entry_rcu(chain, &table->chains, list) {
+				list_for_each_entry_rcu(rule, &chain->rules, list) {
 					if (!nft_rule_is_active(net, rule))
 						goto cont;
 					if (idx < s_idx)
@@ -1572,6 +1594,8 @@ static int nf_tables_dump_rules(struct sk_buff *skb,
 								      NLM_F_MULTI | NLM_F_APPEND,
 								      afi->family, table, chain, rule) < 0)
 						goto done;
+
+					nl_dump_check_consistent(cb, nlmsg_hdr(skb));
 cont:
 					idx++;
 				}
@@ -1579,9 +1603,7 @@ cont:
 		}
 	}
 done:
-	/* Invalidate this dump, a transition to the new generation happened */
-	if (gencursor != net->nft.gencursor || genctr != net->nft.genctr)
-		return -EBUSY;
+	rcu_read_unlock();
 
 	cb->args[0] = idx;
 	return skb->len;
@@ -1932,7 +1954,7 @@ static LIST_HEAD(nf_tables_set_ops);
 int nft_register_set(struct nft_set_ops *ops)
 {
 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
-	list_add_tail(&ops->list, &nf_tables_set_ops);
+	list_add_tail_rcu(&ops->list, &nf_tables_set_ops);
 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
 	return 0;
 }
@@ -1941,7 +1963,7 @@ EXPORT_SYMBOL_GPL(nft_register_set);
 void nft_unregister_set(struct nft_set_ops *ops)
 {
 	nfnl_lock(NFNL_SUBSYS_NFTABLES);
-	list_del(&ops->list);
+	list_del_rcu(&ops->list);
 	nfnl_unlock(NFNL_SUBSYS_NFTABLES);
 }
 EXPORT_SYMBOL_GPL(nft_unregister_set);
@@ -2234,7 +2256,10 @@ static int nf_tables_dump_sets_table(struct nft_ctx *ctx, struct sk_buff *skb,
 	if (cb->args[1])
 		return skb->len;
 
-	list_for_each_entry(set, &ctx->table->sets, list) {
+	rcu_read_lock();
+	cb->seq = ctx->net->nft.base_seq;
+
+	list_for_each_entry_rcu(set, &ctx->table->sets, list) {
 		if (idx < s_idx)
 			goto cont;
 		if (nf_tables_fill_set(skb, ctx, set, NFT_MSG_NEWSET,
@@ -2242,11 +2267,13 @@ static int nf_tables_dump_sets_table(struct nft_ctx *ctx, struct sk_buff *skb,
 			cb->args[0] = idx;
 			goto done;
 		}
+		nl_dump_check_consistent(cb, nlmsg_hdr(skb));
 cont:
 		idx++;
 	}
 	cb->args[1] = 1;
 done:
+	rcu_read_unlock();
 	return skb->len;
 }
 
@@ -2260,7 +2287,10 @@ static int nf_tables_dump_sets_family(struct nft_ctx *ctx, struct sk_buff *skb,
 	if (cb->args[1])
 		return skb->len;
 
-	list_for_each_entry(table, &ctx->afi->tables, list) {
+	rcu_read_lock();
+	cb->seq = ctx->net->nft.base_seq;
+
+	list_for_each_entry_rcu(table, &ctx->afi->tables, list) {
 		if (cur_table) {
 			if (cur_table != table)
 				continue;
@@ -2269,7 +2299,7 @@ static int nf_tables_dump_sets_family(struct nft_ctx *ctx, struct sk_buff *skb,
 		}
 		ctx->table = table;
 		idx = 0;
-		list_for_each_entry(set, &ctx->table->sets, list) {
+		list_for_each_entry_rcu(set, &ctx->table->sets, list) {
 			if (idx < s_idx)
 				goto cont;
 			if (nf_tables_fill_set(skb, ctx, set, NFT_MSG_NEWSET,
@@ -2278,12 +2308,14 @@ static int nf_tables_dump_sets_family(struct nft_ctx *ctx, struct sk_buff *skb,
 				cb->args[2] = (unsigned long) table;
 				goto done;
 			}
+			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
 cont:
 			idx++;
 		}
 	}
 	cb->args[1] = 1;
 done:
+	rcu_read_unlock();
 	return skb->len;
 }
 
@@ -2300,7 +2332,10 @@ static int nf_tables_dump_sets_all(struct nft_ctx *ctx, struct sk_buff *skb,
 	if (cb->args[1])
 		return skb->len;
 
-	list_for_each_entry(afi, &net->nft.af_info, list) {
+	rcu_read_lock();
+	cb->seq = net->nft.base_seq;
+
+	list_for_each_entry_rcu(afi, &net->nft.af_info, list) {
 		if (cur_family) {
 			if (afi->family != cur_family)
 				continue;
@@ -2308,7 +2343,7 @@ static int nf_tables_dump_sets_all(struct nft_ctx *ctx, struct sk_buff *skb,
 			cur_family = 0;
 		}
 
-		list_for_each_entry(table, &afi->tables, list) {
+		list_for_each_entry_rcu(table, &afi->tables, list) {
 			if (cur_table) {
 				if (cur_table != table)
 					continue;
@@ -2319,7 +2354,7 @@ static int nf_tables_dump_sets_all(struct nft_ctx *ctx, struct sk_buff *skb,
 			ctx->table = table;
 			ctx->afi = afi;
 			idx = 0;
-			list_for_each_entry(set, &ctx->table->sets, list) {
+			list_for_each_entry_rcu(set, &ctx->table->sets, list) {
 				if (idx < s_idx)
 					goto cont;
 				if (nf_tables_fill_set(skb, ctx, set,
@@ -2330,6 +2365,7 @@ static int nf_tables_dump_sets_all(struct nft_ctx *ctx, struct sk_buff *skb,
 					cb->args[3] = afi->family;
 					goto done;
 				}
+				nl_dump_check_consistent(cb, nlmsg_hdr(skb));
 cont:
 				idx++;
 			}
@@ -2339,6 +2375,7 @@ cont:
 	}
 	cb->args[1] = 1;
 done:
+	rcu_read_unlock();
 	return skb->len;
 }
 
@@ -2597,7 +2634,7 @@ static int nf_tables_newset(struct sock *nlsk, struct sk_buff *skb,
 	if (err < 0)
 		goto err2;
 
-	list_add_tail(&set->list, &table->sets);
+	list_add_tail_rcu(&set->list, &table->sets);
 	table->use++;
 	return 0;
 
@@ -2617,7 +2654,7 @@ static void nft_set_destroy(struct nft_set *set)
 
 static void nf_tables_set_destroy(const struct nft_ctx *ctx, struct nft_set *set)
 {
-	list_del(&set->list);
+	list_del_rcu(&set->list);
 	nf_tables_set_notify(ctx, set, NFT_MSG_DELSET, GFP_ATOMIC);
 	nft_set_destroy(set);
 }
@@ -2652,7 +2689,7 @@ static int nf_tables_delset(struct sock *nlsk, struct sk_buff *skb,
 	if (err < 0)
 		return err;
 
-	list_del(&set->list);
+	list_del_rcu(&set->list);
 	ctx.table->use--;
 	return 0;
 }
@@ -2704,14 +2741,14 @@ int nf_tables_bind_set(const struct nft_ctx *ctx, struct nft_set *set,
 	}
 bind:
 	binding->chain = ctx->chain;
-	list_add_tail(&binding->list, &set->bindings);
+	list_add_tail_rcu(&binding->list, &set->bindings);
 	return 0;
 }
 
 void nf_tables_unbind_set(const struct nft_ctx *ctx, struct nft_set *set,
 			  struct nft_set_binding *binding)
 {
-	list_del(&binding->list);
+	list_del_rcu(&binding->list);
 
 	if (list_empty(&set->bindings) && set->flags & NFT_SET_ANONYMOUS &&
 	    !(set->flags & NFT_SET_INACTIVE))
@@ -3346,7 +3383,7 @@ static int nf_tables_commit(struct sk_buff *skb)
 	struct nft_set *set;
 
 	/* Bump generation counter, invalidate any dump in progress */
-	net->nft.genctr++;
+	while (++net->nft.base_seq == 0);
 
 	/* A new generation has just started */
 	net->nft.gencursor = gencursor_next(net);
@@ -3491,12 +3528,12 @@ static int nf_tables_abort(struct sk_buff *skb)
 				}
 				nft_trans_destroy(trans);
 			} else {
-				list_del(&trans->ctx.table->list);
+				list_del_rcu(&trans->ctx.table->list);
 			}
 			break;
 		case NFT_MSG_DELTABLE:
-			list_add_tail(&trans->ctx.table->list,
-				      &trans->ctx.afi->tables);
+			list_add_tail_rcu(&trans->ctx.table->list,
+					  &trans->ctx.afi->tables);
 			nft_trans_destroy(trans);
 			break;
 		case NFT_MSG_NEWCHAIN:
@@ -3507,7 +3544,7 @@ static int nf_tables_abort(struct sk_buff *skb)
 				nft_trans_destroy(trans);
 			} else {
 				trans->ctx.table->use--;
-				list_del(&trans->ctx.chain->list);
+				list_del_rcu(&trans->ctx.chain->list);
 				if (!(trans->ctx.table->flags & NFT_TABLE_F_DORMANT) &&
 				    trans->ctx.chain->flags & NFT_BASE_CHAIN) {
 					nf_unregister_hooks(nft_base_chain(trans->ctx.chain)->ops,
@@ -3517,8 +3554,8 @@ static int nf_tables_abort(struct sk_buff *skb)
 			break;
 		case NFT_MSG_DELCHAIN:
 			trans->ctx.table->use++;
-			list_add_tail(&trans->ctx.chain->list,
-				      &trans->ctx.table->chains);
+			list_add_tail_rcu(&trans->ctx.chain->list,
+					  &trans->ctx.table->chains);
 			nft_trans_destroy(trans);
 			break;
 		case NFT_MSG_NEWRULE:
@@ -3532,12 +3569,12 @@ static int nf_tables_abort(struct sk_buff *skb)
 			break;
 		case NFT_MSG_NEWSET:
 			trans->ctx.table->use--;
-			list_del(&nft_trans_set(trans)->list);
+			list_del_rcu(&nft_trans_set(trans)->list);
 			break;
 		case NFT_MSG_DELSET:
 			trans->ctx.table->use++;
-			list_add_tail(&nft_trans_set(trans)->list,
-				      &trans->ctx.table->sets);
+			list_add_tail_rcu(&nft_trans_set(trans)->list,
+					  &trans->ctx.table->sets);
 			nft_trans_destroy(trans);
 			break;
 		case NFT_MSG_NEWSETELEM:
@@ -3951,6 +3988,7 @@ static int nf_tables_init_net(struct net *net)
 {
 	INIT_LIST_HEAD(&net->nft.af_info);
 	INIT_LIST_HEAD(&net->nft.commit_list);
+	net->nft.base_seq = 1;
 	return 0;
 }
 
diff --git a/net/netfilter/nf_tables_core.c b/net/netfilter/nf_tables_core.c
index 345acfb1720b..3b90eb2b2c55 100644
--- a/net/netfilter/nf_tables_core.c
+++ b/net/netfilter/nf_tables_core.c
@@ -109,7 +109,7 @@ nft_do_chain(struct nft_pktinfo *pkt, const struct nf_hook_ops *ops)
 	struct nft_data data[NFT_REG_MAX + 1];
 	unsigned int stackptr = 0;
 	struct nft_jumpstack jumpstack[NFT_JUMP_STACK_SIZE];
-	struct nft_stats __percpu *stats;
+	struct nft_stats *stats;
 	int rulenum;
 	/*
 	 * Cache cursor to avoid problems in case that the cursor is updated
@@ -205,9 +205,11 @@ next_rule:
 		nft_trace_packet(pkt, basechain, -1, NFT_TRACE_POLICY);
 
 	rcu_read_lock_bh();
-	stats = rcu_dereference(nft_base_chain(basechain)->stats);
-	__this_cpu_inc(stats->pkts);
-	__this_cpu_add(stats->bytes, pkt->skb->len);
+	stats = this_cpu_ptr(rcu_dereference(nft_base_chain(basechain)->stats));
+	u64_stats_update_begin(&stats->syncp);
+	stats->pkts++;
+	stats->bytes += pkt->skb->len;
+	u64_stats_update_end(&stats->syncp);
 	rcu_read_unlock_bh();
 
 	return nft_base_chain(basechain)->policy;