[PATCH 0/7] Netfilter fixes for net

[PATCH 0/7] Netfilter fixes for net

[Pablo Neira Ayuso]

Hi,

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

1) Unaligned atomic access in ipset, from Russell King.

2) Missing module description, from Rob Gill.

3) Patches to fix a module unload causing NULL pointer dereference in
   xtables, from David Wilder. For the record, I posting here his cover
   letter explaining the problem:

    A crash happened on ppc64le when running ltp network tests triggered by
    "rmmod iptable_mangle".

    See previous discussion in this thread:
    https://lists.openwall.net/netdev/2020/06/03/161 .

    In the crash I found in iptable_mangle_hook() that
    state->net->ipv4.iptable_mangle=NULL causing a NULL pointer dereference.
    net->ipv4.iptable_mangle is set to NULL in +iptable_mangle_net_exit() and
    called when ip_mangle modules is unloaded. A rmmod task was found running
    in the crash dump.  A 2nd crash showed the same problem when running
    "rmmod iptable_filter" (net->ipv4.iptable_filter=NULL).

    To fix this I added .pre_exit hook in all iptable_foo.c. The pre_exit will
    un-register the underlying hook and exit would do the table freeing. The
    netns core does an unconditional +synchronize_rcu after the pre_exit hooks
    insuring no packets are in flight that have picked up the pointer before
    completing the un-register.

    These patches include changes for both iptables and ip6tables.

    We tested this fix with ltp running iptables01.sh and iptables01.sh -6 a
    loop for 72 hours.

4) Add a selftest for conntrack helper assignment, from Florian Westphal.

Please, pull these changes from:

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

Thank you.

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

The following changes since commit 67c20de35a3cc2e2cd940f95ebd85ed0a765315a:

  net: Add MODULE_DESCRIPTION entries to network modules (2020-06-20 21:33:57 -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 619ae8e0697a6fb85b99b19137590c7c337c579e:

  selftests: netfilter: add test case for conntrack helper assignment (2020-06-25 00:50:31 +0200)

----------------------------------------------------------------
David Wilder (4):
      netfilter: iptables: Split ipt_unregister_table() into pre_exit and exit helpers.
      netfilter: iptables: Add a .pre_exit hook in all iptable_foo.c.
      netfilter: ip6tables: Split ip6t_unregister_table() into pre_exit and exit helpers.
      netfilter: ip6tables: Add a .pre_exit hook in all ip6table_foo.c.

Florian Westphal (1):
      selftests: netfilter: add test case for conntrack helper assignment

Rob Gill (1):
      netfilter: Add MODULE_DESCRIPTION entries to kernel modules

Russell King (1):
      netfilter: ipset: fix unaligned atomic access

 include/linux/netfilter_ipv4/ip_tables.h           |   6 +
 include/linux/netfilter_ipv6/ip6_tables.h          |   3 +
 net/bridge/netfilter/nft_meta_bridge.c             |   1 +
 net/bridge/netfilter/nft_reject_bridge.c           |   1 +
 net/ipv4/netfilter/ip_tables.c                     |  15 +-
 net/ipv4/netfilter/ipt_SYNPROXY.c                  |   1 +
 net/ipv4/netfilter/iptable_filter.c                |  10 +-
 net/ipv4/netfilter/iptable_mangle.c                |  10 +-
 net/ipv4/netfilter/iptable_nat.c                   |  10 +-
 net/ipv4/netfilter/iptable_raw.c                   |  10 +-
 net/ipv4/netfilter/iptable_security.c              |  11 +-
 net/ipv4/netfilter/nf_flow_table_ipv4.c            |   1 +
 net/ipv4/netfilter/nft_dup_ipv4.c                  |   1 +
 net/ipv4/netfilter/nft_fib_ipv4.c                  |   1 +
 net/ipv4/netfilter/nft_reject_ipv4.c               |   1 +
 net/ipv6/netfilter/ip6_tables.c                    |  15 +-
 net/ipv6/netfilter/ip6t_SYNPROXY.c                 |   1 +
 net/ipv6/netfilter/ip6table_filter.c               |  10 +-
 net/ipv6/netfilter/ip6table_mangle.c               |  10 +-
 net/ipv6/netfilter/ip6table_nat.c                  |  10 +-
 net/ipv6/netfilter/ip6table_raw.c                  |  10 +-
 net/ipv6/netfilter/ip6table_security.c             |  10 +-
 net/ipv6/netfilter/nf_flow_table_ipv6.c            |   1 +
 net/ipv6/netfilter/nft_dup_ipv6.c                  |   1 +
 net/ipv6/netfilter/nft_fib_ipv6.c                  |   1 +
 net/ipv6/netfilter/nft_reject_ipv6.c               |   1 +
 net/netfilter/ipset/ip_set_core.c                  |   2 +
 net/netfilter/nf_dup_netdev.c                      |   1 +
 net/netfilter/nf_flow_table_core.c                 |   1 +
 net/netfilter/nf_flow_table_inet.c                 |   1 +
 net/netfilter/nf_synproxy_core.c                   |   1 +
 net/netfilter/nfnetlink.c                          |   1 +
 net/netfilter/nft_compat.c                         |   1 +
 net/netfilter/nft_connlimit.c                      |   1 +
 net/netfilter/nft_counter.c                        |   1 +
 net/netfilter/nft_ct.c                             |   1 +
 net/netfilter/nft_dup_netdev.c                     |   1 +
 net/netfilter/nft_fib_inet.c                       |   1 +
 net/netfilter/nft_fib_netdev.c                     |   1 +
 net/netfilter/nft_flow_offload.c                   |   1 +
 net/netfilter/nft_hash.c                           |   1 +
 net/netfilter/nft_limit.c                          |   1 +
 net/netfilter/nft_log.c                            |   1 +
 net/netfilter/nft_masq.c                           |   1 +
 net/netfilter/nft_nat.c                            |   1 +
 net/netfilter/nft_numgen.c                         |   1 +
 net/netfilter/nft_objref.c                         |   1 +
 net/netfilter/nft_osf.c                            |   1 +
 net/netfilter/nft_queue.c                          |   1 +
 net/netfilter/nft_quota.c                          |   1 +
 net/netfilter/nft_redir.c                          |   1 +
 net/netfilter/nft_reject.c                         |   1 +
 net/netfilter/nft_reject_inet.c                    |   1 +
 net/netfilter/nft_synproxy.c                       |   1 +
 net/netfilter/nft_tunnel.c                         |   1 +
 net/netfilter/xt_nat.c                             |   1 +
 tools/testing/selftests/netfilter/Makefile         |   2 +-
 .../selftests/netfilter/nft_conntrack_helper.sh    | 175 +++++++++++++++++++++
 58 files changed, 344 insertions(+), 16 deletions(-)
 create mode 100755 tools/testing/selftests/netfilter/nft_conntrack_helper.sh

[PATCH 1/7] netfilter: ipset: fix unaligned atomic access

[Pablo Neira Ayuso]

From: Russell King <rmk+kernel@armlinux.org.uk>

When using ip_set with counters and comment, traffic causes the kernel
to panic on 32-bit ARM:

Alignment trap: not handling instruction e1b82f9f at [<bf01b0dc>]
Unhandled fault: alignment exception (0x221) at 0xea08133c
PC is at ip_set_match_extensions+0xe0/0x224 [ip_set]

The problem occurs when we try to update the 64-bit counters - the
faulting address above is not 64-bit aligned.  The problem occurs
due to the way elements are allocated, for example:

	set->dsize = ip_set_elem_len(set, tb, 0, 0);
	map = ip_set_alloc(sizeof(*map) + elements * set->dsize);

If the element has a requirement for a member to be 64-bit aligned,
and set->dsize is not a multiple of 8, but is a multiple of four,
then every odd numbered elements will be misaligned - and hitting
an atomic64_add() on that element will cause the kernel to panic.

ip_set_elem_len() must return a size that is rounded to the maximum
alignment of any extension field stored in the element.  This change
ensures that is the case.

Fixes: 95ad1f4a9358 ("netfilter: ipset: Fix extension alignment")
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/ipset/ip_set_core.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c
index 340cb955af25..56621d6bfd29 100644
--- a/net/netfilter/ipset/ip_set_core.c
+++ b/net/netfilter/ipset/ip_set_core.c
@@ -460,6 +460,8 @@ ip_set_elem_len(struct ip_set *set, struct nlattr *tb[], size_t len,
 	for (id = 0; id < IPSET_EXT_ID_MAX; id++) {
 		if (!add_extension(id, cadt_flags, tb))
 			continue;
+		if (align < ip_set_extensions[id].align)
+			align = ip_set_extensions[id].align;
 		len = ALIGN(len, ip_set_extensions[id].align);
 		set->offset[id] = len;
 		set->extensions |= ip_set_extensions[id].type;
-- 
2.20.1

[PATCH 2/7] netfilter: Add MODULE_DESCRIPTION entries to kernel modules

[Pablo Neira Ayuso]

From: Rob Gill <rrobgill@protonmail.com>

The user tool modinfo is used to get information on kernel modules, including a
description where it is available.

This patch adds a brief MODULE_DESCRIPTION to netfilter kernel modules
(descriptions taken from Kconfig file or code comments)

Signed-off-by: Rob Gill <rrobgill@protonmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/bridge/netfilter/nft_meta_bridge.c   | 1 +
 net/bridge/netfilter/nft_reject_bridge.c | 1 +
 net/ipv4/netfilter/ipt_SYNPROXY.c        | 1 +
 net/ipv4/netfilter/nf_flow_table_ipv4.c  | 1 +
 net/ipv4/netfilter/nft_dup_ipv4.c        | 1 +
 net/ipv4/netfilter/nft_fib_ipv4.c        | 1 +
 net/ipv4/netfilter/nft_reject_ipv4.c     | 1 +
 net/ipv6/netfilter/ip6t_SYNPROXY.c       | 1 +
 net/ipv6/netfilter/nf_flow_table_ipv6.c  | 1 +
 net/ipv6/netfilter/nft_dup_ipv6.c        | 1 +
 net/ipv6/netfilter/nft_fib_ipv6.c        | 1 +
 net/ipv6/netfilter/nft_reject_ipv6.c     | 1 +
 net/netfilter/nf_dup_netdev.c            | 1 +
 net/netfilter/nf_flow_table_core.c       | 1 +
 net/netfilter/nf_flow_table_inet.c       | 1 +
 net/netfilter/nf_synproxy_core.c         | 1 +
 net/netfilter/nfnetlink.c                | 1 +
 net/netfilter/nft_compat.c               | 1 +
 net/netfilter/nft_connlimit.c            | 1 +
 net/netfilter/nft_counter.c              | 1 +
 net/netfilter/nft_ct.c                   | 1 +
 net/netfilter/nft_dup_netdev.c           | 1 +
 net/netfilter/nft_fib_inet.c             | 1 +
 net/netfilter/nft_fib_netdev.c           | 1 +
 net/netfilter/nft_flow_offload.c         | 1 +
 net/netfilter/nft_hash.c                 | 1 +
 net/netfilter/nft_limit.c                | 1 +
 net/netfilter/nft_log.c                  | 1 +
 net/netfilter/nft_masq.c                 | 1 +
 net/netfilter/nft_nat.c                  | 1 +
 net/netfilter/nft_numgen.c               | 1 +
 net/netfilter/nft_objref.c               | 1 +
 net/netfilter/nft_osf.c                  | 1 +
 net/netfilter/nft_queue.c                | 1 +
 net/netfilter/nft_quota.c                | 1 +
 net/netfilter/nft_redir.c                | 1 +
 net/netfilter/nft_reject.c               | 1 +
 net/netfilter/nft_reject_inet.c          | 1 +
 net/netfilter/nft_synproxy.c             | 1 +
 net/netfilter/nft_tunnel.c               | 1 +
 net/netfilter/xt_nat.c                   | 1 +
 41 files changed, 41 insertions(+)

diff --git a/net/bridge/netfilter/nft_meta_bridge.c b/net/bridge/netfilter/nft_meta_bridge.c
index 7c9e92b2f806..8e8ffac037cd 100644
--- a/net/bridge/netfilter/nft_meta_bridge.c
+++ b/net/bridge/netfilter/nft_meta_bridge.c
@@ -155,3 +155,4 @@ module_exit(nft_meta_bridge_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("wenxu <wenxu@ucloud.cn>");
 MODULE_ALIAS_NFT_AF_EXPR(AF_BRIDGE, "meta");
+MODULE_DESCRIPTION("Support for bridge dedicated meta key");
diff --git a/net/bridge/netfilter/nft_reject_bridge.c b/net/bridge/netfilter/nft_reject_bridge.c
index f48cf4cfb80f..deae2c9a0f69 100644
--- a/net/bridge/netfilter/nft_reject_bridge.c
+++ b/net/bridge/netfilter/nft_reject_bridge.c
@@ -455,3 +455,4 @@ module_exit(nft_reject_bridge_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
 MODULE_ALIAS_NFT_AF_EXPR(AF_BRIDGE, "reject");
+MODULE_DESCRIPTION("Reject packets from bridge via nftables");
diff --git a/net/ipv4/netfilter/ipt_SYNPROXY.c b/net/ipv4/netfilter/ipt_SYNPROXY.c
index 748dc3ce58d3..f2984c7eef40 100644
--- a/net/ipv4/netfilter/ipt_SYNPROXY.c
+++ b/net/ipv4/netfilter/ipt_SYNPROXY.c
@@ -118,3 +118,4 @@ module_exit(synproxy_tg4_exit);
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
+MODULE_DESCRIPTION("Intercept TCP connections and establish them using syncookies");
diff --git a/net/ipv4/netfilter/nf_flow_table_ipv4.c b/net/ipv4/netfilter/nf_flow_table_ipv4.c
index e32e41b99f0f..aba65fe90345 100644
--- a/net/ipv4/netfilter/nf_flow_table_ipv4.c
+++ b/net/ipv4/netfilter/nf_flow_table_ipv4.c
@@ -34,3 +34,4 @@ module_exit(nf_flow_ipv4_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
 MODULE_ALIAS_NF_FLOWTABLE(AF_INET);
+MODULE_DESCRIPTION("Netfilter flow table support");
diff --git a/net/ipv4/netfilter/nft_dup_ipv4.c b/net/ipv4/netfilter/nft_dup_ipv4.c
index abf89b972094..bcdb37f86a94 100644
--- a/net/ipv4/netfilter/nft_dup_ipv4.c
+++ b/net/ipv4/netfilter/nft_dup_ipv4.c
@@ -107,3 +107,4 @@ module_exit(nft_dup_ipv4_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
 MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "dup");
+MODULE_DESCRIPTION("IPv4 nftables packet duplication support");
diff --git a/net/ipv4/netfilter/nft_fib_ipv4.c b/net/ipv4/netfilter/nft_fib_ipv4.c
index ce294113dbcd..03df986217b7 100644
--- a/net/ipv4/netfilter/nft_fib_ipv4.c
+++ b/net/ipv4/netfilter/nft_fib_ipv4.c
@@ -210,3 +210,4 @@ module_exit(nft_fib4_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Florian Westphal <fw@strlen.de>");
 MODULE_ALIAS_NFT_AF_EXPR(2, "fib");
+MODULE_DESCRIPTION("nftables fib / ip route lookup support");
diff --git a/net/ipv4/netfilter/nft_reject_ipv4.c b/net/ipv4/netfilter/nft_reject_ipv4.c
index 7e6fd5cde50f..e408f813f5d8 100644
--- a/net/ipv4/netfilter/nft_reject_ipv4.c
+++ b/net/ipv4/netfilter/nft_reject_ipv4.c
@@ -71,3 +71,4 @@ module_exit(nft_reject_ipv4_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "reject");
+MODULE_DESCRIPTION("IPv4 packet rejection for nftables");
diff --git a/net/ipv6/netfilter/ip6t_SYNPROXY.c b/net/ipv6/netfilter/ip6t_SYNPROXY.c
index fd1f52a21bf1..d51d0c3e5fe9 100644
--- a/net/ipv6/netfilter/ip6t_SYNPROXY.c
+++ b/net/ipv6/netfilter/ip6t_SYNPROXY.c
@@ -121,3 +121,4 @@ module_exit(synproxy_tg6_exit);
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
+MODULE_DESCRIPTION("Intercept IPv6 TCP connections and establish them using syncookies");
diff --git a/net/ipv6/netfilter/nf_flow_table_ipv6.c b/net/ipv6/netfilter/nf_flow_table_ipv6.c
index a8566ee12e83..667b8af2546a 100644
--- a/net/ipv6/netfilter/nf_flow_table_ipv6.c
+++ b/net/ipv6/netfilter/nf_flow_table_ipv6.c
@@ -35,3 +35,4 @@ module_exit(nf_flow_ipv6_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
 MODULE_ALIAS_NF_FLOWTABLE(AF_INET6);
+MODULE_DESCRIPTION("Netfilter flow table IPv6 module");
diff --git a/net/ipv6/netfilter/nft_dup_ipv6.c b/net/ipv6/netfilter/nft_dup_ipv6.c
index 2af32200507d..8b5193efb1f1 100644
--- a/net/ipv6/netfilter/nft_dup_ipv6.c
+++ b/net/ipv6/netfilter/nft_dup_ipv6.c
@@ -105,3 +105,4 @@ module_exit(nft_dup_ipv6_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
 MODULE_ALIAS_NFT_AF_EXPR(AF_INET6, "dup");
+MODULE_DESCRIPTION("IPv6 nftables packet duplication support");
diff --git a/net/ipv6/netfilter/nft_fib_ipv6.c b/net/ipv6/netfilter/nft_fib_ipv6.c
index 7ece86afd079..e204163c7036 100644
--- a/net/ipv6/netfilter/nft_fib_ipv6.c
+++ b/net/ipv6/netfilter/nft_fib_ipv6.c
@@ -255,3 +255,4 @@ module_exit(nft_fib6_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Florian Westphal <fw@strlen.de>");
 MODULE_ALIAS_NFT_AF_EXPR(10, "fib");
+MODULE_DESCRIPTION("nftables fib / ipv6 route lookup support");
diff --git a/net/ipv6/netfilter/nft_reject_ipv6.c b/net/ipv6/netfilter/nft_reject_ipv6.c
index 680a28ce29fd..c1098a1968e1 100644
--- a/net/ipv6/netfilter/nft_reject_ipv6.c
+++ b/net/ipv6/netfilter/nft_reject_ipv6.c
@@ -72,3 +72,4 @@ module_exit(nft_reject_ipv6_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 MODULE_ALIAS_NFT_AF_EXPR(AF_INET6, "reject");
+MODULE_DESCRIPTION("IPv6 packet rejection for nftables");
diff --git a/net/netfilter/nf_dup_netdev.c b/net/netfilter/nf_dup_netdev.c
index f108a76925dd..2b01a151eaa8 100644
--- a/net/netfilter/nf_dup_netdev.c
+++ b/net/netfilter/nf_dup_netdev.c
@@ -73,3 +73,4 @@ EXPORT_SYMBOL_GPL(nft_fwd_dup_netdev_offload);
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
+MODULE_DESCRIPTION("Netfilter packet duplication support");
diff --git a/net/netfilter/nf_flow_table_core.c b/net/netfilter/nf_flow_table_core.c
index afa85171df38..b1eb5272b379 100644
--- a/net/netfilter/nf_flow_table_core.c
+++ b/net/netfilter/nf_flow_table_core.c
@@ -594,3 +594,4 @@ module_exit(nf_flow_table_module_exit);
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
+MODULE_DESCRIPTION("Netfilter flow table module");
diff --git a/net/netfilter/nf_flow_table_inet.c b/net/netfilter/nf_flow_table_inet.c
index 88bedf1ff1ae..bc4126d8ef65 100644
--- a/net/netfilter/nf_flow_table_inet.c
+++ b/net/netfilter/nf_flow_table_inet.c
@@ -72,3 +72,4 @@ module_exit(nf_flow_inet_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
 MODULE_ALIAS_NF_FLOWTABLE(1); /* NFPROTO_INET */
+MODULE_DESCRIPTION("Netfilter flow table mixed IPv4/IPv6 module");
diff --git a/net/netfilter/nf_synproxy_core.c b/net/netfilter/nf_synproxy_core.c
index b9cbe1e2453e..ebcdc8e54476 100644
--- a/net/netfilter/nf_synproxy_core.c
+++ b/net/netfilter/nf_synproxy_core.c
@@ -1237,3 +1237,4 @@ EXPORT_SYMBOL_GPL(nf_synproxy_ipv6_fini);
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
+MODULE_DESCRIPTION("nftables SYNPROXY expression support");
diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c
index 99127e2d95a8..5f24edf95830 100644
--- a/net/netfilter/nfnetlink.c
+++ b/net/netfilter/nfnetlink.c
@@ -33,6 +33,7 @@
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
 MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_NETFILTER);
+MODULE_DESCRIPTION("Netfilter messages via netlink socket");
 
 #define nfnl_dereference_protected(id) \
 	rcu_dereference_protected(table[(id)].subsys, \
diff --git a/net/netfilter/nft_compat.c b/net/netfilter/nft_compat.c
index f9adca62ccb3..aa1a066cb74b 100644
--- a/net/netfilter/nft_compat.c
+++ b/net/netfilter/nft_compat.c
@@ -902,3 +902,4 @@ MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
 MODULE_ALIAS_NFT_EXPR("match");
 MODULE_ALIAS_NFT_EXPR("target");
+MODULE_DESCRIPTION("x_tables over nftables support");
diff --git a/net/netfilter/nft_connlimit.c b/net/netfilter/nft_connlimit.c
index 69d6173f91e2..7d0761fad37e 100644
--- a/net/netfilter/nft_connlimit.c
+++ b/net/netfilter/nft_connlimit.c
@@ -280,3 +280,4 @@ MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso");
 MODULE_ALIAS_NFT_EXPR("connlimit");
 MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CONNLIMIT);
+MODULE_DESCRIPTION("nftables connlimit rule support");
diff --git a/net/netfilter/nft_counter.c b/net/netfilter/nft_counter.c
index f6d4d0fa23a6..85ed461ec24e 100644
--- a/net/netfilter/nft_counter.c
+++ b/net/netfilter/nft_counter.c
@@ -303,3 +303,4 @@ MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 MODULE_ALIAS_NFT_EXPR("counter");
 MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_COUNTER);
+MODULE_DESCRIPTION("nftables counter rule support");
diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c
index faea72c2df32..77258af1fce0 100644
--- a/net/netfilter/nft_ct.c
+++ b/net/netfilter/nft_ct.c
@@ -1345,3 +1345,4 @@ MODULE_ALIAS_NFT_EXPR("notrack");
 MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_HELPER);
 MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_TIMEOUT);
 MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_EXPECT);
+MODULE_DESCRIPTION("Netfilter nf_tables conntrack module");
diff --git a/net/netfilter/nft_dup_netdev.c b/net/netfilter/nft_dup_netdev.c
index c2e78c160fd7..40788b3f1071 100644
--- a/net/netfilter/nft_dup_netdev.c
+++ b/net/netfilter/nft_dup_netdev.c
@@ -102,3 +102,4 @@ module_exit(nft_dup_netdev_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
 MODULE_ALIAS_NFT_AF_EXPR(5, "dup");
+MODULE_DESCRIPTION("nftables netdev packet duplication support");
diff --git a/net/netfilter/nft_fib_inet.c b/net/netfilter/nft_fib_inet.c
index 465432e0531b..a88d44e163d1 100644
--- a/net/netfilter/nft_fib_inet.c
+++ b/net/netfilter/nft_fib_inet.c
@@ -76,3 +76,4 @@ module_exit(nft_fib_inet_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Florian Westphal <fw@strlen.de>");
 MODULE_ALIAS_NFT_AF_EXPR(1, "fib");
+MODULE_DESCRIPTION("nftables fib inet support");
diff --git a/net/netfilter/nft_fib_netdev.c b/net/netfilter/nft_fib_netdev.c
index a2e726ae7f07..3f3478abd845 100644
--- a/net/netfilter/nft_fib_netdev.c
+++ b/net/netfilter/nft_fib_netdev.c
@@ -85,3 +85,4 @@ module_exit(nft_fib_netdev_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo M. Bermudo Garay <pablombg@gmail.com>");
 MODULE_ALIAS_NFT_AF_EXPR(5, "fib");
+MODULE_DESCRIPTION("nftables netdev fib lookups support");
diff --git a/net/netfilter/nft_flow_offload.c b/net/netfilter/nft_flow_offload.c
index b70b48996801..3b9b97aa4b32 100644
--- a/net/netfilter/nft_flow_offload.c
+++ b/net/netfilter/nft_flow_offload.c
@@ -286,3 +286,4 @@ module_exit(nft_flow_offload_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
 MODULE_ALIAS_NFT_EXPR("flow_offload");
+MODULE_DESCRIPTION("nftables hardware flow offload module");
diff --git a/net/netfilter/nft_hash.c b/net/netfilter/nft_hash.c
index b836d550b919..96371d878e7e 100644
--- a/net/netfilter/nft_hash.c
+++ b/net/netfilter/nft_hash.c
@@ -248,3 +248,4 @@ module_exit(nft_hash_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Laura Garcia <nevola@gmail.com>");
 MODULE_ALIAS_NFT_EXPR("hash");
+MODULE_DESCRIPTION("Netfilter nftables hash module");
diff --git a/net/netfilter/nft_limit.c b/net/netfilter/nft_limit.c
index 35b67d7e3694..0e2c315c3b5e 100644
--- a/net/netfilter/nft_limit.c
+++ b/net/netfilter/nft_limit.c
@@ -372,3 +372,4 @@ MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 MODULE_ALIAS_NFT_EXPR("limit");
 MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_LIMIT);
+MODULE_DESCRIPTION("nftables limit expression support");
diff --git a/net/netfilter/nft_log.c b/net/netfilter/nft_log.c
index fe4831f2258f..57899454a530 100644
--- a/net/netfilter/nft_log.c
+++ b/net/netfilter/nft_log.c
@@ -298,3 +298,4 @@ module_exit(nft_log_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 MODULE_ALIAS_NFT_EXPR("log");
+MODULE_DESCRIPTION("Netfilter nf_tables log module");
diff --git a/net/netfilter/nft_masq.c b/net/netfilter/nft_masq.c
index bc9fd98c5d6d..71390b727040 100644
--- a/net/netfilter/nft_masq.c
+++ b/net/netfilter/nft_masq.c
@@ -305,3 +305,4 @@ module_exit(nft_masq_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Arturo Borrero Gonzalez <arturo@debian.org>");
 MODULE_ALIAS_NFT_EXPR("masq");
+MODULE_DESCRIPTION("Netfilter nftables masquerade expression support");
diff --git a/net/netfilter/nft_nat.c b/net/netfilter/nft_nat.c
index 23a7bfd10521..4bcf33b049c4 100644
--- a/net/netfilter/nft_nat.c
+++ b/net/netfilter/nft_nat.c
@@ -402,3 +402,4 @@ module_exit(nft_nat_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>");
 MODULE_ALIAS_NFT_EXPR("nat");
+MODULE_DESCRIPTION("Network Address Translation support");
diff --git a/net/netfilter/nft_numgen.c b/net/netfilter/nft_numgen.c
index 48edb9d5f012..f1fc824f9737 100644
--- a/net/netfilter/nft_numgen.c
+++ b/net/netfilter/nft_numgen.c
@@ -217,3 +217,4 @@ module_exit(nft_ng_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Laura Garcia <nevola@gmail.com>");
 MODULE_ALIAS_NFT_EXPR("numgen");
+MODULE_DESCRIPTION("nftables number generator module");
diff --git a/net/netfilter/nft_objref.c b/net/netfilter/nft_objref.c
index bfd18d2b65a2..5f9207a9f485 100644
--- a/net/netfilter/nft_objref.c
+++ b/net/netfilter/nft_objref.c
@@ -252,3 +252,4 @@ module_exit(nft_objref_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
 MODULE_ALIAS_NFT_EXPR("objref");
+MODULE_DESCRIPTION("nftables stateful object reference module");
diff --git a/net/netfilter/nft_osf.c b/net/netfilter/nft_osf.c
index b42247aa48a9..c261d57a666a 100644
--- a/net/netfilter/nft_osf.c
+++ b/net/netfilter/nft_osf.c
@@ -149,3 +149,4 @@ module_exit(nft_osf_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Fernando Fernandez <ffmancera@riseup.net>");
 MODULE_ALIAS_NFT_EXPR("osf");
+MODULE_DESCRIPTION("nftables passive OS fingerprint support");
diff --git a/net/netfilter/nft_queue.c b/net/netfilter/nft_queue.c
index 5ece0a6aa8c3..23265d757acb 100644
--- a/net/netfilter/nft_queue.c
+++ b/net/netfilter/nft_queue.c
@@ -216,3 +216,4 @@ module_exit(nft_queue_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Eric Leblond <eric@regit.org>");
 MODULE_ALIAS_NFT_EXPR("queue");
+MODULE_DESCRIPTION("Netfilter nftables queue module");
diff --git a/net/netfilter/nft_quota.c b/net/netfilter/nft_quota.c
index 4413690591f2..0363f533a42b 100644
--- a/net/netfilter/nft_quota.c
+++ b/net/netfilter/nft_quota.c
@@ -254,3 +254,4 @@ MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
 MODULE_ALIAS_NFT_EXPR("quota");
 MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_QUOTA);
+MODULE_DESCRIPTION("Netfilter nftables quota module");
diff --git a/net/netfilter/nft_redir.c b/net/netfilter/nft_redir.c
index 5b779171565c..2056051c0af0 100644
--- a/net/netfilter/nft_redir.c
+++ b/net/netfilter/nft_redir.c
@@ -292,3 +292,4 @@ module_exit(nft_redir_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Arturo Borrero Gonzalez <arturo@debian.org>");
 MODULE_ALIAS_NFT_EXPR("redir");
+MODULE_DESCRIPTION("Netfilter nftables redirect support");
diff --git a/net/netfilter/nft_reject.c b/net/netfilter/nft_reject.c
index 00f865fb80ca..86eafbb0fdd0 100644
--- a/net/netfilter/nft_reject.c
+++ b/net/netfilter/nft_reject.c
@@ -119,3 +119,4 @@ EXPORT_SYMBOL_GPL(nft_reject_icmpv6_code);
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
+MODULE_DESCRIPTION("Netfilter x_tables over nftables module");
diff --git a/net/netfilter/nft_reject_inet.c b/net/netfilter/nft_reject_inet.c
index f41f414b72d1..cf8f2646e93c 100644
--- a/net/netfilter/nft_reject_inet.c
+++ b/net/netfilter/nft_reject_inet.c
@@ -149,3 +149,4 @@ module_exit(nft_reject_inet_module_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 MODULE_ALIAS_NFT_AF_EXPR(1, "reject");
+MODULE_DESCRIPTION("Netfilter nftables reject inet support");
diff --git a/net/netfilter/nft_synproxy.c b/net/netfilter/nft_synproxy.c
index e2c1fc608841..4fda8b3f1762 100644
--- a/net/netfilter/nft_synproxy.c
+++ b/net/netfilter/nft_synproxy.c
@@ -388,3 +388,4 @@ MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Fernando Fernandez <ffmancera@riseup.net>");
 MODULE_ALIAS_NFT_EXPR("synproxy");
 MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_SYNPROXY);
+MODULE_DESCRIPTION("nftables SYNPROXY expression support");
diff --git a/net/netfilter/nft_tunnel.c b/net/netfilter/nft_tunnel.c
index 30be5787fbde..d3eb953d0333 100644
--- a/net/netfilter/nft_tunnel.c
+++ b/net/netfilter/nft_tunnel.c
@@ -719,3 +719,4 @@ MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
 MODULE_ALIAS_NFT_EXPR("tunnel");
 MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_TUNNEL);
+MODULE_DESCRIPTION("nftables tunnel expression support");
diff --git a/net/netfilter/xt_nat.c b/net/netfilter/xt_nat.c
index a8e5f6c8db7a..b4f7bbc3f3ca 100644
--- a/net/netfilter/xt_nat.c
+++ b/net/netfilter/xt_nat.c
@@ -244,3 +244,4 @@ MODULE_ALIAS("ipt_SNAT");
 MODULE_ALIAS("ipt_DNAT");
 MODULE_ALIAS("ip6t_SNAT");
 MODULE_ALIAS("ip6t_DNAT");
+MODULE_DESCRIPTION("SNAT and DNAT targets support");
-- 
2.20.1

[PATCH 3/7] netfilter: iptables: Split ipt_unregister_table() into pre_exit and exit helpers.

[Pablo Neira Ayuso]

From: David Wilder <dwilder@us.ibm.com>

The pre_exit will un-register the underlying hook and .exit will do the
table freeing. The netns core does an unconditional synchronize_rcu after
the pre_exit hooks insuring no packets are in flight that have picked up
the pointer before completing the un-register.

Fixes: b9e69e127397 ("netfilter: xtables: don't hook tables by default")
Signed-off-by: David Wilder <dwilder@us.ibm.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 include/linux/netfilter_ipv4/ip_tables.h |  6 ++++++
 net/ipv4/netfilter/ip_tables.c           | 15 ++++++++++++++-
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/include/linux/netfilter_ipv4/ip_tables.h b/include/linux/netfilter_ipv4/ip_tables.h
index b394bd4f68a3..c4676d6feeff 100644
--- a/include/linux/netfilter_ipv4/ip_tables.h
+++ b/include/linux/netfilter_ipv4/ip_tables.h
@@ -25,6 +25,12 @@
 int ipt_register_table(struct net *net, const struct xt_table *table,
 		       const struct ipt_replace *repl,
 		       const struct nf_hook_ops *ops, struct xt_table **res);
+
+void ipt_unregister_table_pre_exit(struct net *net, struct xt_table *table,
+		       const struct nf_hook_ops *ops);
+
+void ipt_unregister_table_exit(struct net *net, struct xt_table *table);
+
 void ipt_unregister_table(struct net *net, struct xt_table *table,
 			  const struct nf_hook_ops *ops);
 
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index c2670eaa74e6..5bf9fa06aee0 100644
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -1797,11 +1797,22 @@ int ipt_register_table(struct net *net, const struct xt_table *table,
 	return ret;
 }
 
+void ipt_unregister_table_pre_exit(struct net *net, struct xt_table *table,
+				   const struct nf_hook_ops *ops)
+{
+	nf_unregister_net_hooks(net, ops, hweight32(table->valid_hooks));
+}
+
+void ipt_unregister_table_exit(struct net *net, struct xt_table *table)
+{
+	__ipt_unregister_table(net, table);
+}
+
 void ipt_unregister_table(struct net *net, struct xt_table *table,
 			  const struct nf_hook_ops *ops)
 {
 	if (ops)
-		nf_unregister_net_hooks(net, ops, hweight32(table->valid_hooks));
+		ipt_unregister_table_pre_exit(net, table, ops);
 	__ipt_unregister_table(net, table);
 }
 
@@ -1958,6 +1969,8 @@ static void __exit ip_tables_fini(void)
 
 EXPORT_SYMBOL(ipt_register_table);
 EXPORT_SYMBOL(ipt_unregister_table);
+EXPORT_SYMBOL(ipt_unregister_table_pre_exit);
+EXPORT_SYMBOL(ipt_unregister_table_exit);
 EXPORT_SYMBOL(ipt_do_table);
 module_init(ip_tables_init);
 module_exit(ip_tables_fini);
-- 
2.20.1

[PATCH 4/7] netfilter: iptables: Add a .pre_exit hook in all iptable_foo.c.

[Pablo Neira Ayuso]

From: David Wilder <dwilder@us.ibm.com>

Using new helpers ipt_unregister_table_pre_exit() and
ipt_unregister_table_exit().

Fixes: b9e69e127397 ("netfilter: xtables: don't hook tables by default")
Signed-off-by: David Wilder <dwilder@us.ibm.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/ipv4/netfilter/iptable_filter.c   | 10 +++++++++-
 net/ipv4/netfilter/iptable_mangle.c   | 10 +++++++++-
 net/ipv4/netfilter/iptable_nat.c      | 10 ++++++++--
 net/ipv4/netfilter/iptable_raw.c      | 10 +++++++++-
 net/ipv4/netfilter/iptable_security.c | 11 +++++++++--
 5 files changed, 44 insertions(+), 7 deletions(-)

diff --git a/net/ipv4/netfilter/iptable_filter.c b/net/ipv4/netfilter/iptable_filter.c
index 9d54b4017e50..8f7bc1ee7453 100644
--- a/net/ipv4/netfilter/iptable_filter.c
+++ b/net/ipv4/netfilter/iptable_filter.c
@@ -72,16 +72,24 @@ static int __net_init iptable_filter_net_init(struct net *net)
 	return 0;
 }
 
+static void __net_exit iptable_filter_net_pre_exit(struct net *net)
+{
+	if (net->ipv4.iptable_filter)
+		ipt_unregister_table_pre_exit(net, net->ipv4.iptable_filter,
+					      filter_ops);
+}
+
 static void __net_exit iptable_filter_net_exit(struct net *net)
 {
 	if (!net->ipv4.iptable_filter)
 		return;
-	ipt_unregister_table(net, net->ipv4.iptable_filter, filter_ops);
+	ipt_unregister_table_exit(net, net->ipv4.iptable_filter);
 	net->ipv4.iptable_filter = NULL;
 }
 
 static struct pernet_operations iptable_filter_net_ops = {
 	.init = iptable_filter_net_init,
+	.pre_exit = iptable_filter_net_pre_exit,
 	.exit = iptable_filter_net_exit,
 };
 
diff --git a/net/ipv4/netfilter/iptable_mangle.c b/net/ipv4/netfilter/iptable_mangle.c
index bb9266ea3785..f703a717ab1d 100644
--- a/net/ipv4/netfilter/iptable_mangle.c
+++ b/net/ipv4/netfilter/iptable_mangle.c
@@ -100,15 +100,23 @@ static int __net_init iptable_mangle_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit iptable_mangle_net_pre_exit(struct net *net)
+{
+	if (net->ipv4.iptable_mangle)
+		ipt_unregister_table_pre_exit(net, net->ipv4.iptable_mangle,
+					      mangle_ops);
+}
+
 static void __net_exit iptable_mangle_net_exit(struct net *net)
 {
 	if (!net->ipv4.iptable_mangle)
 		return;
-	ipt_unregister_table(net, net->ipv4.iptable_mangle, mangle_ops);
+	ipt_unregister_table_exit(net, net->ipv4.iptable_mangle);
 	net->ipv4.iptable_mangle = NULL;
 }
 
 static struct pernet_operations iptable_mangle_net_ops = {
+	.pre_exit = iptable_mangle_net_pre_exit,
 	.exit = iptable_mangle_net_exit,
 };
 
diff --git a/net/ipv4/netfilter/iptable_nat.c b/net/ipv4/netfilter/iptable_nat.c
index ad33687b7444..b0143b109f25 100644
--- a/net/ipv4/netfilter/iptable_nat.c
+++ b/net/ipv4/netfilter/iptable_nat.c
@@ -113,16 +113,22 @@ static int __net_init iptable_nat_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit iptable_nat_net_pre_exit(struct net *net)
+{
+	if (net->ipv4.nat_table)
+		ipt_nat_unregister_lookups(net);
+}
+
 static void __net_exit iptable_nat_net_exit(struct net *net)
 {
 	if (!net->ipv4.nat_table)
 		return;
-	ipt_nat_unregister_lookups(net);
-	ipt_unregister_table(net, net->ipv4.nat_table, NULL);
+	ipt_unregister_table_exit(net, net->ipv4.nat_table);
 	net->ipv4.nat_table = NULL;
 }
 
 static struct pernet_operations iptable_nat_net_ops = {
+	.pre_exit = iptable_nat_net_pre_exit,
 	.exit	= iptable_nat_net_exit,
 };
 
diff --git a/net/ipv4/netfilter/iptable_raw.c b/net/ipv4/netfilter/iptable_raw.c
index 69697eb4bfc6..9abfe6bf2cb9 100644
--- a/net/ipv4/netfilter/iptable_raw.c
+++ b/net/ipv4/netfilter/iptable_raw.c
@@ -67,15 +67,23 @@ static int __net_init iptable_raw_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit iptable_raw_net_pre_exit(struct net *net)
+{
+	if (net->ipv4.iptable_raw)
+		ipt_unregister_table_pre_exit(net, net->ipv4.iptable_raw,
+					      rawtable_ops);
+}
+
 static void __net_exit iptable_raw_net_exit(struct net *net)
 {
 	if (!net->ipv4.iptable_raw)
 		return;
-	ipt_unregister_table(net, net->ipv4.iptable_raw, rawtable_ops);
+	ipt_unregister_table_exit(net, net->ipv4.iptable_raw);
 	net->ipv4.iptable_raw = NULL;
 }
 
 static struct pernet_operations iptable_raw_net_ops = {
+	.pre_exit = iptable_raw_net_pre_exit,
 	.exit = iptable_raw_net_exit,
 };
 
diff --git a/net/ipv4/netfilter/iptable_security.c b/net/ipv4/netfilter/iptable_security.c
index ac633c1db97e..415c1975d770 100644
--- a/net/ipv4/netfilter/iptable_security.c
+++ b/net/ipv4/netfilter/iptable_security.c
@@ -62,16 +62,23 @@ static int __net_init iptable_security_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit iptable_security_net_pre_exit(struct net *net)
+{
+	if (net->ipv4.iptable_security)
+		ipt_unregister_table_pre_exit(net, net->ipv4.iptable_security,
+					      sectbl_ops);
+}
+
 static void __net_exit iptable_security_net_exit(struct net *net)
 {
 	if (!net->ipv4.iptable_security)
 		return;
-
-	ipt_unregister_table(net, net->ipv4.iptable_security, sectbl_ops);
+	ipt_unregister_table_exit(net, net->ipv4.iptable_security);
 	net->ipv4.iptable_security = NULL;
 }
 
 static struct pernet_operations iptable_security_net_ops = {
+	.pre_exit = iptable_security_net_pre_exit,
 	.exit = iptable_security_net_exit,
 };
 
-- 
2.20.1

[PATCH 5/7] netfilter: ip6tables: Split ip6t_unregister_table() into pre_exit and exit helpers.

[Pablo Neira Ayuso]

From: David Wilder <dwilder@us.ibm.com>

The pre_exit will un-register the underlying hook and .exit will do
the table freeing. The netns core does an unconditional synchronize_rcu
after the pre_exit hooks insuring no packets are in flight that have
picked up the pointer before completing the un-register.

Fixes: b9e69e127397 ("netfilter: xtables: don't hook tables by default")
Signed-off-by: David Wilder <dwilder@us.ibm.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 include/linux/netfilter_ipv6/ip6_tables.h |  3 +++
 net/ipv6/netfilter/ip6_tables.c           | 15 ++++++++++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/include/linux/netfilter_ipv6/ip6_tables.h b/include/linux/netfilter_ipv6/ip6_tables.h
index 8225f7821a29..1547d5f9ae06 100644
--- a/include/linux/netfilter_ipv6/ip6_tables.h
+++ b/include/linux/netfilter_ipv6/ip6_tables.h
@@ -29,6 +29,9 @@ int ip6t_register_table(struct net *net, const struct xt_table *table,
 			const struct nf_hook_ops *ops, struct xt_table **res);
 void ip6t_unregister_table(struct net *net, struct xt_table *table,
 			   const struct nf_hook_ops *ops);
+void ip6t_unregister_table_pre_exit(struct net *net, struct xt_table *table,
+				    const struct nf_hook_ops *ops);
+void ip6t_unregister_table_exit(struct net *net, struct xt_table *table);
 extern unsigned int ip6t_do_table(struct sk_buff *skb,
 				  const struct nf_hook_state *state,
 				  struct xt_table *table);
diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index e27393498ecb..e96a431549bc 100644
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -1807,11 +1807,22 @@ int ip6t_register_table(struct net *net, const struct xt_table *table,
 	return ret;
 }
 
+void ip6t_unregister_table_pre_exit(struct net *net, struct xt_table *table,
+				    const struct nf_hook_ops *ops)
+{
+	nf_unregister_net_hooks(net, ops, hweight32(table->valid_hooks));
+}
+
+void ip6t_unregister_table_exit(struct net *net, struct xt_table *table)
+{
+	__ip6t_unregister_table(net, table);
+}
+
 void ip6t_unregister_table(struct net *net, struct xt_table *table,
 			   const struct nf_hook_ops *ops)
 {
 	if (ops)
-		nf_unregister_net_hooks(net, ops, hweight32(table->valid_hooks));
+		ip6t_unregister_table_pre_exit(net, table, ops);
 	__ip6t_unregister_table(net, table);
 }
 
@@ -1969,6 +1980,8 @@ static void __exit ip6_tables_fini(void)
 
 EXPORT_SYMBOL(ip6t_register_table);
 EXPORT_SYMBOL(ip6t_unregister_table);
+EXPORT_SYMBOL(ip6t_unregister_table_pre_exit);
+EXPORT_SYMBOL(ip6t_unregister_table_exit);
 EXPORT_SYMBOL(ip6t_do_table);
 
 module_init(ip6_tables_init);
-- 
2.20.1

[PATCH 6/7] netfilter: ip6tables: Add a .pre_exit hook in all ip6table_foo.c.

[Pablo Neira Ayuso]

From: David Wilder <dwilder@us.ibm.com>

Using new helpers ip6t_unregister_table_pre_exit() and
ip6t_unregister_table_exit().

Fixes: b9e69e127397 ("netfilter: xtables: don't hook tables by default")
Signed-off-by: David Wilder <dwilder@us.ibm.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/ipv6/netfilter/ip6table_filter.c   | 10 +++++++++-
 net/ipv6/netfilter/ip6table_mangle.c   | 10 +++++++++-
 net/ipv6/netfilter/ip6table_nat.c      | 10 ++++++++--
 net/ipv6/netfilter/ip6table_raw.c      | 10 +++++++++-
 net/ipv6/netfilter/ip6table_security.c | 10 +++++++++-
 5 files changed, 44 insertions(+), 6 deletions(-)

diff --git a/net/ipv6/netfilter/ip6table_filter.c b/net/ipv6/netfilter/ip6table_filter.c
index 32667f5d5a33..88337b51ffbf 100644
--- a/net/ipv6/netfilter/ip6table_filter.c
+++ b/net/ipv6/netfilter/ip6table_filter.c
@@ -73,16 +73,24 @@ static int __net_init ip6table_filter_net_init(struct net *net)
 	return 0;
 }
 
+static void __net_exit ip6table_filter_net_pre_exit(struct net *net)
+{
+	if (net->ipv6.ip6table_filter)
+		ip6t_unregister_table_pre_exit(net, net->ipv6.ip6table_filter,
+					       filter_ops);
+}
+
 static void __net_exit ip6table_filter_net_exit(struct net *net)
 {
 	if (!net->ipv6.ip6table_filter)
 		return;
-	ip6t_unregister_table(net, net->ipv6.ip6table_filter, filter_ops);
+	ip6t_unregister_table_exit(net, net->ipv6.ip6table_filter);
 	net->ipv6.ip6table_filter = NULL;
 }
 
 static struct pernet_operations ip6table_filter_net_ops = {
 	.init = ip6table_filter_net_init,
+	.pre_exit = ip6table_filter_net_pre_exit,
 	.exit = ip6table_filter_net_exit,
 };
 
diff --git a/net/ipv6/netfilter/ip6table_mangle.c b/net/ipv6/netfilter/ip6table_mangle.c
index 070afb97fa2b..1a2748611e00 100644
--- a/net/ipv6/netfilter/ip6table_mangle.c
+++ b/net/ipv6/netfilter/ip6table_mangle.c
@@ -93,16 +93,24 @@ static int __net_init ip6table_mangle_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit ip6table_mangle_net_pre_exit(struct net *net)
+{
+	if (net->ipv6.ip6table_mangle)
+		ip6t_unregister_table_pre_exit(net, net->ipv6.ip6table_mangle,
+					       mangle_ops);
+}
+
 static void __net_exit ip6table_mangle_net_exit(struct net *net)
 {
 	if (!net->ipv6.ip6table_mangle)
 		return;
 
-	ip6t_unregister_table(net, net->ipv6.ip6table_mangle, mangle_ops);
+	ip6t_unregister_table_exit(net, net->ipv6.ip6table_mangle);
 	net->ipv6.ip6table_mangle = NULL;
 }
 
 static struct pernet_operations ip6table_mangle_net_ops = {
+	.pre_exit = ip6table_mangle_net_pre_exit,
 	.exit = ip6table_mangle_net_exit,
 };
 
diff --git a/net/ipv6/netfilter/ip6table_nat.c b/net/ipv6/netfilter/ip6table_nat.c
index 0f4875952efc..0a23265e3caa 100644
--- a/net/ipv6/netfilter/ip6table_nat.c
+++ b/net/ipv6/netfilter/ip6table_nat.c
@@ -114,16 +114,22 @@ static int __net_init ip6table_nat_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit ip6table_nat_net_pre_exit(struct net *net)
+{
+	if (net->ipv6.ip6table_nat)
+		ip6t_nat_unregister_lookups(net);
+}
+
 static void __net_exit ip6table_nat_net_exit(struct net *net)
 {
 	if (!net->ipv6.ip6table_nat)
 		return;
-	ip6t_nat_unregister_lookups(net);
-	ip6t_unregister_table(net, net->ipv6.ip6table_nat, NULL);
+	ip6t_unregister_table_exit(net, net->ipv6.ip6table_nat);
 	net->ipv6.ip6table_nat = NULL;
 }
 
 static struct pernet_operations ip6table_nat_net_ops = {
+	.pre_exit = ip6table_nat_net_pre_exit,
 	.exit	= ip6table_nat_net_exit,
 };
 
diff --git a/net/ipv6/netfilter/ip6table_raw.c b/net/ipv6/netfilter/ip6table_raw.c
index a22100b1cf2c..8f9e742226f7 100644
--- a/net/ipv6/netfilter/ip6table_raw.c
+++ b/net/ipv6/netfilter/ip6table_raw.c
@@ -66,15 +66,23 @@ static int __net_init ip6table_raw_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit ip6table_raw_net_pre_exit(struct net *net)
+{
+	if (net->ipv6.ip6table_raw)
+		ip6t_unregister_table_pre_exit(net, net->ipv6.ip6table_raw,
+					       rawtable_ops);
+}
+
 static void __net_exit ip6table_raw_net_exit(struct net *net)
 {
 	if (!net->ipv6.ip6table_raw)
 		return;
-	ip6t_unregister_table(net, net->ipv6.ip6table_raw, rawtable_ops);
+	ip6t_unregister_table_exit(net, net->ipv6.ip6table_raw);
 	net->ipv6.ip6table_raw = NULL;
 }
 
 static struct pernet_operations ip6table_raw_net_ops = {
+	.pre_exit = ip6table_raw_net_pre_exit,
 	.exit = ip6table_raw_net_exit,
 };
 
diff --git a/net/ipv6/netfilter/ip6table_security.c b/net/ipv6/netfilter/ip6table_security.c
index a74335fe2bd9..5e8c48fed032 100644
--- a/net/ipv6/netfilter/ip6table_security.c
+++ b/net/ipv6/netfilter/ip6table_security.c
@@ -61,15 +61,23 @@ static int __net_init ip6table_security_table_init(struct net *net)
 	return ret;
 }
 
+static void __net_exit ip6table_security_net_pre_exit(struct net *net)
+{
+	if (net->ipv6.ip6table_security)
+		ip6t_unregister_table_pre_exit(net, net->ipv6.ip6table_security,
+					       sectbl_ops);
+}
+
 static void __net_exit ip6table_security_net_exit(struct net *net)
 {
 	if (!net->ipv6.ip6table_security)
 		return;
-	ip6t_unregister_table(net, net->ipv6.ip6table_security, sectbl_ops);
+	ip6t_unregister_table_exit(net, net->ipv6.ip6table_security);
 	net->ipv6.ip6table_security = NULL;
 }
 
 static struct pernet_operations ip6table_security_net_ops = {
+	.pre_exit = ip6table_security_net_pre_exit,
 	.exit = ip6table_security_net_exit,
 };
 
-- 
2.20.1

[PATCH 7/7] selftests: netfilter: add test case for conntrack helper assignment

[Pablo Neira Ayuso]

From: Florian Westphal <fw@strlen.de>

check that 'nft ... ct helper set <foo>' works:
 1. configure ftp helper via nft and assign it to
    connections on port 2121
 2. check with 'conntrack -L' that the next connection
    has the ftp helper attached to it.

Also add a test for auto-assign (old behaviour).

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 tools/testing/selftests/netfilter/Makefile    |   2 +-
 .../netfilter/nft_conntrack_helper.sh         | 175 ++++++++++++++++++
 2 files changed, 176 insertions(+), 1 deletion(-)
 create mode 100755 tools/testing/selftests/netfilter/nft_conntrack_helper.sh

diff --git a/tools/testing/selftests/netfilter/Makefile b/tools/testing/selftests/netfilter/Makefile
index 9c0f758310fe..a179f0dca8ce 100644
--- a/tools/testing/selftests/netfilter/Makefile
+++ b/tools/testing/selftests/netfilter/Makefile
@@ -3,7 +3,7 @@
 
 TEST_PROGS := nft_trans_stress.sh nft_nat.sh bridge_brouter.sh \
 	conntrack_icmp_related.sh nft_flowtable.sh ipvs.sh \
-	nft_concat_range.sh \
+	nft_concat_range.sh nft_conntrack_helper.sh \
 	nft_queue.sh
 
 LDLIBS = -lmnl
diff --git a/tools/testing/selftests/netfilter/nft_conntrack_helper.sh b/tools/testing/selftests/netfilter/nft_conntrack_helper.sh
new file mode 100755
index 000000000000..edf0a48da6bf
--- /dev/null
+++ b/tools/testing/selftests/netfilter/nft_conntrack_helper.sh
@@ -0,0 +1,175 @@
+#!/bin/bash
+#
+# This tests connection tracking helper assignment:
+# 1. can attach ftp helper to a connection from nft ruleset.
+# 2. auto-assign still works.
+#
+# Kselftest framework requirement - SKIP code is 4.
+ksft_skip=4
+ret=0
+
+sfx=$(mktemp -u "XXXXXXXX")
+ns1="ns1-$sfx"
+ns2="ns2-$sfx"
+testipv6=1
+
+cleanup()
+{
+	ip netns del ${ns1}
+	ip netns del ${ns2}
+}
+
+nft --version > /dev/null 2>&1
+if [ $? -ne 0 ];then
+	echo "SKIP: Could not run test without nft tool"
+	exit $ksft_skip
+fi
+
+ip -Version > /dev/null 2>&1
+if [ $? -ne 0 ];then
+	echo "SKIP: Could not run test without ip tool"
+	exit $ksft_skip
+fi
+
+conntrack -V > /dev/null 2>&1
+if [ $? -ne 0 ];then
+	echo "SKIP: Could not run test without conntrack tool"
+	exit $ksft_skip
+fi
+
+which nc >/dev/null 2>&1
+if [ $? -ne 0 ];then
+	echo "SKIP: Could not run test without netcat tool"
+	exit $ksft_skip
+fi
+
+trap cleanup EXIT
+
+ip netns add ${ns1}
+ip netns add ${ns2}
+
+ip link add veth0 netns ${ns1} type veth peer name veth0 netns ${ns2} > /dev/null 2>&1
+if [ $? -ne 0 ];then
+    echo "SKIP: No virtual ethernet pair device support in kernel"
+    exit $ksft_skip
+fi
+
+ip -net ${ns1} link set lo up
+ip -net ${ns1} link set veth0 up
+
+ip -net ${ns2} link set lo up
+ip -net ${ns2} link set veth0 up
+
+ip -net ${ns1} addr add 10.0.1.1/24 dev veth0
+ip -net ${ns1} addr add dead:1::1/64 dev veth0
+
+ip -net ${ns2} addr add 10.0.1.2/24 dev veth0
+ip -net ${ns2} addr add dead:1::2/64 dev veth0
+
+load_ruleset_family() {
+	local family=$1
+	local ns=$2
+
+ip netns exec ${ns} nft -f - <<EOF
+table $family raw {
+	ct helper ftp {
+             type "ftp" protocol tcp
+        }
+	chain pre {
+		type filter hook prerouting priority 0; policy accept;
+		tcp dport 2121 ct helper set "ftp"
+	}
+	chain output {
+		type filter hook output priority 0; policy accept;
+		tcp dport 2121 ct helper set "ftp"
+	}
+}
+EOF
+	return $?
+}
+
+check_for_helper()
+{
+	local netns=$1
+	local message=$2
+	local port=$3
+
+	ip netns exec ${netns} conntrack -L -p tcp --dport $port 2> /dev/null |grep -q 'helper=ftp'
+	if [ $? -ne 0 ] ; then
+		echo "FAIL: ${netns} did not show attached helper $message" 1>&2
+		ret=1
+	fi
+
+	echo "PASS: ${netns} connection on port $port has ftp helper attached" 1>&2
+	return 0
+}
+
+test_helper()
+{
+	local port=$1
+	local msg=$2
+
+	sleep 3 | ip netns exec ${ns2} nc -w 2 -l -p $port > /dev/null &
+
+	sleep 1
+	sleep 1 | ip netns exec ${ns1} nc -w 2 10.0.1.2 $port > /dev/null &
+
+	check_for_helper "$ns1" "ip $msg" $port
+	check_for_helper "$ns2" "ip $msg" $port
+
+	wait
+
+	if [ $testipv6 -eq 0 ] ;then
+		return 0
+	fi
+
+	ip netns exec ${ns1} conntrack -F 2> /dev/null
+	ip netns exec ${ns2} conntrack -F 2> /dev/null
+
+	sleep 3 | ip netns exec ${ns2} nc -w 2 -6 -l -p $port > /dev/null &
+
+	sleep 1
+	sleep 1 | ip netns exec ${ns1} nc -w 2 -6 dead:1::2 $port > /dev/null &
+
+	check_for_helper "$ns1" "ipv6 $msg" $port
+	check_for_helper "$ns2" "ipv6 $msg" $port
+
+	wait
+}
+
+load_ruleset_family ip ${ns1}
+if [ $? -ne 0 ];then
+	echo "FAIL: ${ns1} cannot load ip ruleset" 1>&2
+	exit 1
+fi
+
+load_ruleset_family ip6 ${ns1}
+if [ $? -ne 0 ];then
+	echo "SKIP: ${ns1} cannot load ip6 ruleset" 1>&2
+	testipv6=0
+fi
+
+load_ruleset_family inet ${ns2}
+if [ $? -ne 0 ];then
+	echo "SKIP: ${ns1} cannot load inet ruleset" 1>&2
+	load_ruleset_family ip ${ns2}
+	if [ $? -ne 0 ];then
+		echo "FAIL: ${ns2} cannot load ip ruleset" 1>&2
+		exit 1
+	fi
+
+	if [ $testipv6 -eq 1 ] ;then
+		load_ruleset_family ip6 ${ns2}
+		if [ $? -ne 0 ];then
+			echo "FAIL: ${ns2} cannot load ip6 ruleset" 1>&2
+			exit 1
+		fi
+	fi
+fi
+
+test_helper 2121 "set via ruleset"
+ip netns exec ${ns1} sysctl -q 'net.netfilter.nf_conntrack_helper=1'
+ip netns exec ${ns2} sysctl -q 'net.netfilter.nf_conntrack_helper=1'
+test_helper 21 "auto-assign"
+
+exit $ret
-- 
2.20.1

Re: [PATCH 0/7] Netfilter fixes for net

[David Miller]

From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Thu, 25 Jun 2020 20:26:28 +0200

> The following patchset contains Netfilter fixes for net, they are:
...
> Please, pull these changes from:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf.git

Pulled, thanks Pablo.