[PATCH 0/8] netfilter fixes for net

[PATCH 0/8] netfilter fixes for net

[Pablo Neira Ayuso]

Hi,

The following patchset contains Netfilter fixes for your net tree:

1) memleak in ebtables from the error path for the 32/64 compat layer,
   from Florian Westphal.

2) Fix inverted meta ifname/ifidx matching when no interface is set
   on either from the input/output path, from Phil Sutter.

3) Remove goto label in nft_meta_bridge, also from Phil.

4) Missing include guard in xt_connlabel, from Masahiro Yamada.

5) Two patch to fix ipset destination MAC matching coming from
   Stephano Brivio, via Jozsef Kadlecsik.

6) Fix set rename and listing concurrency problem, from Shijie Luo.
   Patch also coming via Jozsef Kadlecsik.

7) ebtables 32/64 compat missing base chain policy in rule count,
   from Florian Westphal.

You can pull these changes from:

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

Thanks!

----------------------------------------------------------------

The following changes since commit 0cea0e1148fe134a4a3aaf0b1496f09241fb943a:

  net: phy: sfp: hwmon: Fix scaling of RX power (2019-07-21 11:51:50 -0700)

are available in the git repository at:

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

for you to fetch changes up to 7cdc4412284777c76c919e2ab33b3b8dbed18559:

  Merge branch 'master' of git://blackhole.kfki.hu/nf (2019-07-30 13:39:20 +0200)

----------------------------------------------------------------
Florian Westphal (1):
      netfilter: ebtables: also count base chain policies

Jozsef Kadlecsik (1):
      netfilter: ipset: Fix rename concurrency with listing

Masahiro Yamada (1):
      netfilter: add include guard to xt_connlabel.h

Pablo Neira Ayuso (1):
      Merge branch 'master' of git://blackhole.kfki.hu/nf

Phil Sutter (2):
      netfilter: nf_tables: Make nft_meta expression more robust
      netfilter: nft_meta_bridge: Eliminate 'out' label

Stefano Brivio (2):
      netfilter: ipset: Actually allow destination MAC address for hash:ip,mac sets too
      netfilter: ipset: Copy the right MAC address in bitmap:ip,mac and hash:ip,mac sets

Wenwen Wang (1):
      netfilter: ebtables: fix a memory leak bug in compat

 include/uapi/linux/netfilter/xt_connlabel.h |  6 ++++++
 net/bridge/netfilter/ebtables.c             | 32 ++++++++++++++++++-----------
 net/bridge/netfilter/nft_meta_bridge.c      | 10 ++-------
 net/netfilter/ipset/ip_set_bitmap_ipmac.c   |  2 +-
 net/netfilter/ipset/ip_set_core.c           |  2 +-
 net/netfilter/ipset/ip_set_hash_ipmac.c     |  6 +-----
 net/netfilter/nft_meta.c                    | 16 ++++-----------
 7 files changed, 35 insertions(+), 39 deletions(-)

[PATCH 1/8] netfilter: ebtables: fix a memory leak bug in compat

[Pablo Neira Ayuso]

From: Wenwen Wang <wenwen@cs.uga.edu>

In compat_do_replace(), a temporary buffer is allocated through vmalloc()
to hold entries copied from the user space. The buffer address is firstly
saved to 'newinfo->entries', and later on assigned to 'entries_tmp'. Then
the entries in this temporary buffer is copied to the internal kernel
structure through compat_copy_entries(). If this copy process fails,
compat_do_replace() should be terminated. However, the allocated temporary
buffer is not freed on this path, leading to a memory leak.

To fix the bug, free the buffer before returning from compat_do_replace().

Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/bridge/netfilter/ebtables.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 963dfdc14827..fd84b48e48b5 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -2261,8 +2261,10 @@ static int compat_do_replace(struct net *net, void __user *user,
 	state.buf_kern_len = size64;
 
 	ret = compat_copy_entries(entries_tmp, tmp.entries_size, &state);
-	if (WARN_ON(ret < 0))
+	if (WARN_ON(ret < 0)) {
+		vfree(entries_tmp);
 		goto out_unlock;
+	}
 
 	vfree(entries_tmp);
 	tmp.entries_size = size64;
-- 
2.11.0

[PATCH 2/8] netfilter: nf_tables: Make nft_meta expression more robust

[Pablo Neira Ayuso]

From: Phil Sutter <phil@nwl.cc>

nft_meta_get_eval()'s tendency to bail out setting NFT_BREAK verdict in
situations where required data is missing leads to unexpected behaviour
with inverted checks like so:

| meta iifname != eth0 accept

This rule will never match if there is no input interface (or it is not
known) which is not intuitive and, what's worse, breaks consistency of
iptables-nft with iptables-legacy.

Fix this by falling back to placing a value in dreg which never matches
(avoiding accidental matches), i.e. zero for interface index and an
empty string for interface name.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/bridge/netfilter/nft_meta_bridge.c |  6 +-----
 net/netfilter/nft_meta.c               | 16 ++++------------
 2 files changed, 5 insertions(+), 17 deletions(-)

diff --git a/net/bridge/netfilter/nft_meta_bridge.c b/net/bridge/netfilter/nft_meta_bridge.c
index bed66f536b34..a98dec2cf0cf 100644
--- a/net/bridge/netfilter/nft_meta_bridge.c
+++ b/net/bridge/netfilter/nft_meta_bridge.c
@@ -30,13 +30,9 @@ static void nft_meta_bridge_get_eval(const struct nft_expr *expr,
 	switch (priv->key) {
 	case NFT_META_BRI_IIFNAME:
 		br_dev = nft_meta_get_bridge(in);
-		if (!br_dev)
-			goto err;
 		break;
 	case NFT_META_BRI_OIFNAME:
 		br_dev = nft_meta_get_bridge(out);
-		if (!br_dev)
-			goto err;
 		break;
 	case NFT_META_BRI_IIFPVID: {
 		u16 p_pvid;
@@ -64,7 +60,7 @@ static void nft_meta_bridge_get_eval(const struct nft_expr *expr,
 		goto out;
 	}
 
-	strncpy((char *)dest, br_dev->name, IFNAMSIZ);
+	strncpy((char *)dest, br_dev ? br_dev->name : "", IFNAMSIZ);
 	return;
 out:
 	return nft_meta_get_eval(expr, regs, pkt);
diff --git a/net/netfilter/nft_meta.c b/net/netfilter/nft_meta.c
index f1b1d948c07b..f69afb9ff3cb 100644
--- a/net/netfilter/nft_meta.c
+++ b/net/netfilter/nft_meta.c
@@ -60,24 +60,16 @@ void nft_meta_get_eval(const struct nft_expr *expr,
 		*dest = skb->mark;
 		break;
 	case NFT_META_IIF:
-		if (in == NULL)
-			goto err;
-		*dest = in->ifindex;
+		*dest = in ? in->ifindex : 0;
 		break;
 	case NFT_META_OIF:
-		if (out == NULL)
-			goto err;
-		*dest = out->ifindex;
+		*dest = out ? out->ifindex : 0;
 		break;
 	case NFT_META_IIFNAME:
-		if (in == NULL)
-			goto err;
-		strncpy((char *)dest, in->name, IFNAMSIZ);
+		strncpy((char *)dest, in ? in->name : "", IFNAMSIZ);
 		break;
 	case NFT_META_OIFNAME:
-		if (out == NULL)
-			goto err;
-		strncpy((char *)dest, out->name, IFNAMSIZ);
+		strncpy((char *)dest, out ? out->name : "", IFNAMSIZ);
 		break;
 	case NFT_META_IIFTYPE:
 		if (in == NULL)
-- 
2.11.0

[PATCH 3/8] netfilter: nft_meta_bridge: Eliminate 'out' label

[Pablo Neira Ayuso]

From: Phil Sutter <phil@nwl.cc>

The label is used just once and the code it points at is not reused, no
point in keeping it.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/bridge/netfilter/nft_meta_bridge.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/net/bridge/netfilter/nft_meta_bridge.c b/net/bridge/netfilter/nft_meta_bridge.c
index a98dec2cf0cf..1804e867f715 100644
--- a/net/bridge/netfilter/nft_meta_bridge.c
+++ b/net/bridge/netfilter/nft_meta_bridge.c
@@ -57,13 +57,11 @@ static void nft_meta_bridge_get_eval(const struct nft_expr *expr,
 		return;
 	}
 	default:
-		goto out;
+		return nft_meta_get_eval(expr, regs, pkt);
 	}
 
 	strncpy((char *)dest, br_dev ? br_dev->name : "", IFNAMSIZ);
 	return;
-out:
-	return nft_meta_get_eval(expr, regs, pkt);
 err:
 	regs->verdict.code = NFT_BREAK;
 }
-- 
2.11.0

[PATCH 4/8] netfilter: add include guard to xt_connlabel.h

[Pablo Neira Ayuso]

From: Masahiro Yamada <yamada.masahiro@socionext.com>

Add a header include guard just in case.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 include/uapi/linux/netfilter/xt_connlabel.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/include/uapi/linux/netfilter/xt_connlabel.h b/include/uapi/linux/netfilter/xt_connlabel.h
index 2312f0ec07b2..323f0dfc2a4e 100644
--- a/include/uapi/linux/netfilter/xt_connlabel.h
+++ b/include/uapi/linux/netfilter/xt_connlabel.h
@@ -1,4 +1,8 @@
 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+
+#ifndef _UAPI_XT_CONNLABEL_H
+#define _UAPI_XT_CONNLABEL_H
+
 #include <linux/types.h>
 
 #define XT_CONNLABEL_MAXBIT 127
@@ -11,3 +15,5 @@ struct xt_connlabel_mtinfo {
 	__u16 bit;
 	__u16 options;
 };
+
+#endif /* _UAPI_XT_CONNLABEL_H */
-- 
2.11.0

[PATCH 5/8] netfilter: ipset: Actually allow destination MAC address for hash:ip,mac sets too

[Pablo Neira Ayuso]

From: Stefano Brivio <sbrivio@redhat.com>

In commit 8cc4ccf58379 ("ipset: Allow matching on destination MAC address
for mac and ipmac sets"), ipset.git commit 1543514c46a7, I removed the
KADT check that prevents matching on destination MAC addresses for
hash:mac sets, but forgot to remove the same check for hash:ip,mac set.

Drop this check: functionality is now commented in man pages and there's
no reason to restrict to source MAC address matching anymore.

Reported-by: Chen Yi <yiche@redhat.com>
Fixes: 8cc4ccf58379 ("ipset: Allow matching on destination MAC address for mac and ipmac sets")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
---
 net/netfilter/ipset/ip_set_hash_ipmac.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/net/netfilter/ipset/ip_set_hash_ipmac.c b/net/netfilter/ipset/ip_set_hash_ipmac.c
index faf59b6a998f..eb1443408320 100644
--- a/net/netfilter/ipset/ip_set_hash_ipmac.c
+++ b/net/netfilter/ipset/ip_set_hash_ipmac.c
@@ -89,10 +89,6 @@ hash_ipmac4_kadt(struct ip_set *set, const struct sk_buff *skb,
 	struct hash_ipmac4_elem e = { .ip = 0, { .foo[0] = 0, .foo[1] = 0 } };
 	struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
 
-	 /* MAC can be src only */
-	if (!(opt->flags & IPSET_DIM_TWO_SRC))
-		return 0;
-
 	if (skb_mac_header(skb) < skb->head ||
 	    (skb_mac_header(skb) + ETH_HLEN) > skb->data)
 		return -EINVAL;
-- 
2.11.0

[PATCH 6/8] netfilter: ipset: Copy the right MAC address in bitmap:ip,mac and hash:ip,mac sets

[Pablo Neira Ayuso]

From: Stefano Brivio <sbrivio@redhat.com>

In commit 8cc4ccf58379 ("ipset: Allow matching on destination MAC address
for mac and ipmac sets"), ipset.git commit 1543514c46a7, I added to the
KADT functions for sets matching on MAC addreses the copy of source or
destination MAC address depending on the configured match.

This was done correctly for hash:mac, but for hash:ip,mac and
bitmap:ip,mac, copying and pasting the same code block presents an
obvious problem: in these two set types, the MAC address is the second
dimension, not the first one, and we are actually selecting the MAC
address depending on whether the first dimension (IP address) specifies
source or destination.

Fix this by checking for the IPSET_DIM_TWO_SRC flag in option flags.

This way, mixing source and destination matches for the two dimensions
of ip,mac set types works as expected. With this setup:

  ip netns add A
  ip link add veth1 type veth peer name veth2 netns A
  ip addr add 192.0.2.1/24 dev veth1
  ip -net A addr add 192.0.2.2/24 dev veth2
  ip link set veth1 up
  ip -net A link set veth2 up

  dst=$(ip netns exec A cat /sys/class/net/veth2/address)

  ip netns exec A ipset create test_bitmap bitmap:ip,mac range 192.0.0.0/16
  ip netns exec A ipset add test_bitmap 192.0.2.1,${dst}
  ip netns exec A iptables -A INPUT -m set ! --match-set test_bitmap src,dst -j DROP

  ip netns exec A ipset create test_hash hash:ip,mac
  ip netns exec A ipset add test_hash 192.0.2.1,${dst}
  ip netns exec A iptables -A INPUT -m set ! --match-set test_hash src,dst -j DROP

ipset correctly matches a test packet:

  # ping -c1 192.0.2.2 >/dev/null
  # echo $?
  0

Reported-by: Chen Yi <yiche@redhat.com>
Fixes: 8cc4ccf58379 ("ipset: Allow matching on destination MAC address for mac and ipmac sets")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
---
 net/netfilter/ipset/ip_set_bitmap_ipmac.c | 2 +-
 net/netfilter/ipset/ip_set_hash_ipmac.c   | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/netfilter/ipset/ip_set_bitmap_ipmac.c b/net/netfilter/ipset/ip_set_bitmap_ipmac.c
index ca7ac4a25ada..1d4e63326e68 100644
--- a/net/netfilter/ipset/ip_set_bitmap_ipmac.c
+++ b/net/netfilter/ipset/ip_set_bitmap_ipmac.c
@@ -226,7 +226,7 @@ bitmap_ipmac_kadt(struct ip_set *set, const struct sk_buff *skb,
 
 	e.id = ip_to_id(map, ip);
 
-	if (opt->flags & IPSET_DIM_ONE_SRC)
+	if (opt->flags & IPSET_DIM_TWO_SRC)
 		ether_addr_copy(e.ether, eth_hdr(skb)->h_source);
 	else
 		ether_addr_copy(e.ether, eth_hdr(skb)->h_dest);
diff --git a/net/netfilter/ipset/ip_set_hash_ipmac.c b/net/netfilter/ipset/ip_set_hash_ipmac.c
index eb1443408320..24d8f4df4230 100644
--- a/net/netfilter/ipset/ip_set_hash_ipmac.c
+++ b/net/netfilter/ipset/ip_set_hash_ipmac.c
@@ -93,7 +93,7 @@ hash_ipmac4_kadt(struct ip_set *set, const struct sk_buff *skb,
 	    (skb_mac_header(skb) + ETH_HLEN) > skb->data)
 		return -EINVAL;
 
-	if (opt->flags & IPSET_DIM_ONE_SRC)
+	if (opt->flags & IPSET_DIM_TWO_SRC)
 		ether_addr_copy(e.ether, eth_hdr(skb)->h_source);
 	else
 		ether_addr_copy(e.ether, eth_hdr(skb)->h_dest);
-- 
2.11.0

[PATCH 7/8] netfilter: ipset: Fix rename concurrency with listing

[Pablo Neira Ayuso]

From: Jozsef Kadlecsik <kadlec@netfilter.org>

Shijie Luo reported that when stress-testing ipset with multiple concurrent
create, rename, flush, list, destroy commands, it can result

ipset <version>: Broken LIST kernel message: missing DATA part!

error messages and broken list results. The problem was the rename operation
was not properly handled with respect of listing. The patch fixes the issue.

Reported-by: Shijie Luo <luoshijie1@huawei.com>
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
---
 net/netfilter/ipset/ip_set_core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c
index 2e151856ad99..e64d5f9a89dd 100644
--- a/net/netfilter/ipset/ip_set_core.c
+++ b/net/netfilter/ipset/ip_set_core.c
@@ -1161,7 +1161,7 @@ static int ip_set_rename(struct net *net, struct sock *ctnl,
 		return -ENOENT;
 
 	write_lock_bh(&ip_set_ref_lock);
-	if (set->ref != 0) {
+	if (set->ref != 0 || set->ref_netlink != 0) {
 		ret = -IPSET_ERR_REFERENCED;
 		goto out;
 	}
-- 
2.11.0

[PATCH 8/8] netfilter: ebtables: also count base chain policies

[Pablo Neira Ayuso]

From: Florian Westphal <fw@strlen.de>

ebtables doesn't include the base chain policies in the rule count,
so we need to add them manually when we call into the x_tables core
to allocate space for the comapt offset table.

This lead syzbot to trigger:
WARNING: CPU: 1 PID: 9012 at net/netfilter/x_tables.c:649
xt_compat_add_offset.cold+0x11/0x36 net/netfilter/x_tables.c:649

Reported-by: syzbot+276ddebab3382bbf72db@syzkaller.appspotmail.com
Fixes: 2035f3ff8eaa ("netfilter: ebtables: compat: un-break 32bit setsockopt when no rules are present")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/bridge/netfilter/ebtables.c | 28 +++++++++++++++++-----------
 1 file changed, 17 insertions(+), 11 deletions(-)

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index fd84b48e48b5..c8177a89f52c 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -1770,20 +1770,28 @@ static int compat_calc_entry(const struct ebt_entry *e,
 	return 0;
 }
 
+static int ebt_compat_init_offsets(unsigned int number)
+{
+	if (number > INT_MAX)
+		return -EINVAL;
+
+	/* also count the base chain policies */
+	number += NF_BR_NUMHOOKS;
+
+	return xt_compat_init_offsets(NFPROTO_BRIDGE, number);
+}
 
 static int compat_table_info(const struct ebt_table_info *info,
 			     struct compat_ebt_replace *newinfo)
 {
 	unsigned int size = info->entries_size;
 	const void *entries = info->entries;
+	int ret;
 
 	newinfo->entries_size = size;
-	if (info->nentries) {
-		int ret = xt_compat_init_offsets(NFPROTO_BRIDGE,
-						 info->nentries);
-		if (ret)
-			return ret;
-	}
+	ret = ebt_compat_init_offsets(info->nentries);
+	if (ret)
+		return ret;
 
 	return EBT_ENTRY_ITERATE(entries, size, compat_calc_entry, info,
 							entries, newinfo);
@@ -2234,11 +2242,9 @@ static int compat_do_replace(struct net *net, void __user *user,
 
 	xt_compat_lock(NFPROTO_BRIDGE);
 
-	if (tmp.nentries) {
-		ret = xt_compat_init_offsets(NFPROTO_BRIDGE, tmp.nentries);
-		if (ret < 0)
-			goto out_unlock;
-	}
+	ret = ebt_compat_init_offsets(tmp.nentries);
+	if (ret < 0)
+		goto out_unlock;
 
 	ret = compat_copy_entries(entries_tmp, tmp.entries_size, &state);
 	if (ret < 0)
-- 
2.11.0

Re: [PATCH 0/8] netfilter fixes for net

[David Miller]

From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Wed, 31 Jul 2019 13:51:49 +0200

> The following patchset contains Netfilter fixes for your net tree:
 ...
> You can pull these changes from:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf.git

Pulled, thanks.