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 net:

1) Fix endianness issue in flowtable TCP flags dissector,
   from Arnd Bergmann.

2) Extend flowtable test script with dnat rules, from Florian Westphal.

3) Reject padding in ebtables user entries and validate computed user
   offset, reported by syzbot, from Florian Westphal.

4) Fix endianness in nft_tproxy, from Phil Sutter.
====================

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

4 files changed, 53 insertions, 25 deletions

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 4096d8a74a2b..e1256e03a9a8 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -1867,7 +1867,7 @@ static int ebt_buf_count(struct ebt_entries_buf_state *state, unsigned int sz)
 }
 
 static int ebt_buf_add(struct ebt_entries_buf_state *state,
-		       void *data, unsigned int sz)
+		       const void *data, unsigned int sz)
 {
 	if (state->buf_kern_start == NULL)
 		goto count_only;
@@ -1901,7 +1901,7 @@ enum compat_mwt {
 	EBT_COMPAT_TARGET,
 };
 
-static int compat_mtw_from_user(struct compat_ebt_entry_mwt *mwt,
+static int compat_mtw_from_user(const struct compat_ebt_entry_mwt *mwt,
 				enum compat_mwt compat_mwt,
 				struct ebt_entries_buf_state *state,
 				const unsigned char *base)
@@ -1979,22 +1979,23 @@ static int compat_mtw_from_user(struct compat_ebt_entry_mwt *mwt,
 /* return size of all matches, watchers or target, including necessary
  * alignment and padding.
  */
-static int ebt_size_mwt(struct compat_ebt_entry_mwt *match32,
+static int ebt_size_mwt(const struct compat_ebt_entry_mwt *match32,
 			unsigned int size_left, enum compat_mwt type,
 			struct ebt_entries_buf_state *state, const void *base)
 {
+	const char *buf = (const char *)match32;
 	int growth = 0;
-	char *buf;
 
 	if (size_left == 0)
 		return 0;
 
-	buf = (char *) match32;
-
-	while (size_left >= sizeof(*match32)) {
+	do {
 		struct ebt_entry_match *match_kern;
 		int ret;
 
+		if (size_left < sizeof(*match32))
+			return -EINVAL;
+
 		match_kern = (struct ebt_entry_match *) state->buf_kern_start;
 		if (match_kern) {
 			char *tmp;
@@ -2031,22 +2032,18 @@ static int ebt_size_mwt(struct compat_ebt_entry_mwt *match32,
 		if (match_kern)
 			match_kern->match_size = ret;
 
-		/* rule should have no remaining data after target */
-		if (type == EBT_COMPAT_TARGET && size_left)
-			return -EINVAL;
-
 		match32 = (struct compat_ebt_entry_mwt *) buf;
-	}
+	} while (size_left);
 
 	return growth;
 }
 
 /* called for all ebt_entry structures. */
-static int size_entry_mwt(struct ebt_entry *entry, const unsigned char *base,
+static int size_entry_mwt(const struct ebt_entry *entry, const unsigned char *base,
 			  unsigned int *total,
 			  struct ebt_entries_buf_state *state)
 {
-	unsigned int i, j, startoff, new_offset = 0;
+	unsigned int i, j, startoff, next_expected_off, new_offset = 0;
 	/* stores match/watchers/targets & offset of next struct ebt_entry: */
 	unsigned int offsets[4];
 	unsigned int *offsets_update = NULL;
@@ -2132,11 +2129,13 @@ static int size_entry_mwt(struct ebt_entry *entry, const unsigned char *base,
 			return ret;
 	}
 
-	startoff = state->buf_user_offset - startoff;
+	next_expected_off = state->buf_user_offset - startoff;
+	if (next_expected_off != entry->next_offset)
+		return -EINVAL;
 
-	if (WARN_ON(*total < startoff))
+	if (*total < entry->next_offset)
 		return -EINVAL;
-	*total -= startoff;
+	*total -= entry->next_offset;
 	return 0;
 }
 
diff --git a/net/netfilter/nf_flow_table_offload.c b/net/netfilter/nf_flow_table_offload.c
index de7a0d1e15c8..0d72e5ccb47b 100644
--- a/net/netfilter/nf_flow_table_offload.c
+++ b/net/netfilter/nf_flow_table_offload.c
@@ -88,7 +88,7 @@ static int nf_flow_rule_match(struct nf_flow_match *match,
 	switch (tuple->l4proto) {
 	case IPPROTO_TCP:
 		key->tcp.flags = 0;
-		mask->tcp.flags = TCP_FLAG_RST | TCP_FLAG_FIN;
+		mask->tcp.flags = cpu_to_be16(be32_to_cpu(TCP_FLAG_RST | TCP_FLAG_FIN) >> 16);
 		match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_TCP);
 		break;
 	case IPPROTO_UDP:
diff --git a/net/netfilter/nft_tproxy.c b/net/netfilter/nft_tproxy.c
index 4c33dfc9dab5..d67f83a0958d 100644
--- a/net/netfilter/nft_tproxy.c
+++ b/net/netfilter/nft_tproxy.c
@@ -50,7 +50,7 @@ static void nft_tproxy_eval_v4(const struct nft_expr *expr,
 	taddr = nf_tproxy_laddr4(skb, taddr, iph->daddr);
 
 	if (priv->sreg_port)
-		tport = regs->data[priv->sreg_port];
+		tport = nft_reg_load16(&regs->data[priv->sreg_port]);
 	if (!tport)
 		tport = hp->dest;
 
@@ -117,7 +117,7 @@ static void nft_tproxy_eval_v6(const struct nft_expr *expr,
 	taddr = *nf_tproxy_laddr6(skb, &taddr, &iph->daddr);
 
 	if (priv->sreg_port)
-		tport = regs->data[priv->sreg_port];
+		tport = nft_reg_load16(&regs->data[priv->sreg_port]);
 	if (!tport)
 		tport = hp->dest;
 
diff --git a/tools/testing/selftests/netfilter/nft_flowtable.sh b/tools/testing/selftests/netfilter/nft_flowtable.sh
index 16571ac1dab4..d3e0809ab368 100755
--- a/tools/testing/selftests/netfilter/nft_flowtable.sh
+++ b/tools/testing/selftests/netfilter/nft_flowtable.sh
@@ -226,17 +226,19 @@ check_transfer()
 	return 0
 }
 
-test_tcp_forwarding()
+test_tcp_forwarding_ip()
 {
 	local nsa=$1
 	local nsb=$2
+	local dstip=$3
+	local dstport=$4
 	local lret=0
 
 	ip netns exec $nsb nc -w 5 -l -p 12345 < "$ns2in" > "$ns2out" &
 	lpid=$!
 
 	sleep 1
-	ip netns exec $nsa nc -w 4 10.0.2.99 12345 < "$ns1in" > "$ns1out" &
+	ip netns exec $nsa nc -w 4 "$dstip" "$dstport" < "$ns1in" > "$ns1out" &
 	cpid=$!
 
 	sleep 3
@@ -258,6 +260,28 @@ test_tcp_forwarding()
 	return $lret
 }
 
+test_tcp_forwarding()
+{
+	test_tcp_forwarding_ip "$1" "$2" 10.0.2.99 12345
+
+	return $?
+}
+
+test_tcp_forwarding_nat()
+{
+	local lret
+
+	test_tcp_forwarding_ip "$1" "$2" 10.0.2.99 12345
+	lret=$?
+
+	if [ $lret -eq 0 ] ; then
+		test_tcp_forwarding_ip "$1" "$2" 10.6.6.6 1666
+		lret=$?
+	fi
+
+	return $lret
+}
+
 make_file "$ns1in" "ns1"
 make_file "$ns2in" "ns2"
 
@@ -283,14 +307,19 @@ ip -net ns2 route add 192.168.10.1 via 10.0.2.1
 # Same, but with NAT enabled.
 ip netns exec nsr1 nft -f - <<EOF
 table ip nat {
+   chain prerouting {
+      type nat hook prerouting priority 0; policy accept;
+      meta iif "veth0" ip daddr 10.6.6.6 tcp dport 1666 counter dnat ip to 10.0.2.99:12345
+   }
+
    chain postrouting {
       type nat hook postrouting priority 0; policy accept;
-      meta oifname "veth1" masquerade
+      meta oifname "veth1" counter masquerade
    }
 }
 EOF
 
-test_tcp_forwarding ns1 ns2
+test_tcp_forwarding_nat ns1 ns2
 
 if [ $? -eq 0 ] ;then
 	echo "PASS: flow offloaded for ns1/ns2 with NAT"
@@ -313,7 +342,7 @@ fi
 ip netns exec ns1 sysctl net.ipv4.ip_no_pmtu_disc=0 > /dev/null
 ip netns exec ns2 sysctl net.ipv4.ip_no_pmtu_disc=0 > /dev/null
 
-test_tcp_forwarding ns1 ns2
+test_tcp_forwarding_nat ns1 ns2
 if [ $? -eq 0 ] ;then
 	echo "PASS: flow offloaded for ns1/ns2 with NAT and pmtu discovery"
 else