From: Florian Westphal <fw@strlen.de>
To: <netfilter-devel@vger.kernel.org>
Cc: tristan@talencesecurity.com, Florian Westphal <fw@strlen.de>
Subject: [PATCH v3 nf 4/8] netfilter: x_tables: unregister the templates first
Date: Wed, 6 May 2026 12:07:16 +0200 [thread overview]
Message-ID: <20260506100728.2664-5-fw@strlen.de> (raw)
In-Reply-To: <20260506100728.2664-1-fw@strlen.de>
When the module is going away we need to zap the template
first. Else there is a small race window where userspace
could instantiate a new table after the pernet exit function
has removed the current table.
Fixes: fdacd57c79b7 ("netfilter: x_tables: never register tables by default")
Reported-by: Tristan Madani <tristan@talencesecurity.com>
Reviewed-by: Tristan Madani <tristan@talencesecurity.com>
Closes: https://lore.kernel.org/netfilter-devel/20260429175613.1459342-1-tristmd@gmail.com/
Signed-off-by: Florian Westphal <fw@strlen.de>
---
v3: no changes.
net/ipv4/netfilter/arptable_filter.c | 2 +-
net/ipv4/netfilter/iptable_filter.c | 2 +-
net/ipv4/netfilter/iptable_mangle.c | 2 +-
net/ipv4/netfilter/iptable_raw.c | 2 +-
net/ipv4/netfilter/iptable_security.c | 2 +-
net/ipv6/netfilter/ip6table_filter.c | 2 +-
net/ipv6/netfilter/ip6table_mangle.c | 2 +-
net/ipv6/netfilter/ip6table_raw.c | 2 +-
net/ipv6/netfilter/ip6table_security.c | 2 +-
9 files changed, 9 insertions(+), 9 deletions(-)
diff --git a/net/ipv4/netfilter/arptable_filter.c b/net/ipv4/netfilter/arptable_filter.c
index 393d9a8c7739..382345567a60 100644
--- a/net/ipv4/netfilter/arptable_filter.c
+++ b/net/ipv4/netfilter/arptable_filter.c
@@ -82,8 +82,8 @@ static int __init arptable_filter_init(void)
static void __exit arptable_filter_fini(void)
{
- unregister_pernet_subsys(&arptable_filter_net_ops);
xt_unregister_template(&packet_filter);
+ unregister_pernet_subsys(&arptable_filter_net_ops);
kfree(arpfilter_ops);
}
diff --git a/net/ipv4/netfilter/iptable_filter.c b/net/ipv4/netfilter/iptable_filter.c
index b2fbd9651d61..0dea754a9120 100644
--- a/net/ipv4/netfilter/iptable_filter.c
+++ b/net/ipv4/netfilter/iptable_filter.c
@@ -101,8 +101,8 @@ static int __init iptable_filter_init(void)
static void __exit iptable_filter_fini(void)
{
- unregister_pernet_subsys(&iptable_filter_net_ops);
xt_unregister_template(&packet_filter);
+ unregister_pernet_subsys(&iptable_filter_net_ops);
kfree(filter_ops);
}
diff --git a/net/ipv4/netfilter/iptable_mangle.c b/net/ipv4/netfilter/iptable_mangle.c
index a99e61996197..4d3b12492308 100644
--- a/net/ipv4/netfilter/iptable_mangle.c
+++ b/net/ipv4/netfilter/iptable_mangle.c
@@ -135,8 +135,8 @@ static int __init iptable_mangle_init(void)
static void __exit iptable_mangle_fini(void)
{
- unregister_pernet_subsys(&iptable_mangle_net_ops);
xt_unregister_template(&packet_mangler);
+ unregister_pernet_subsys(&iptable_mangle_net_ops);
kfree(mangle_ops);
}
diff --git a/net/ipv4/netfilter/iptable_raw.c b/net/ipv4/netfilter/iptable_raw.c
index 42511721e538..6f7afec7954b 100644
--- a/net/ipv4/netfilter/iptable_raw.c
+++ b/net/ipv4/netfilter/iptable_raw.c
@@ -100,9 +100,9 @@ static int __init iptable_raw_init(void)
static void __exit iptable_raw_fini(void)
{
+ xt_unregister_template(&packet_raw);
unregister_pernet_subsys(&iptable_raw_net_ops);
kfree(rawtable_ops);
- xt_unregister_template(&packet_raw);
}
module_init(iptable_raw_init);
diff --git a/net/ipv4/netfilter/iptable_security.c b/net/ipv4/netfilter/iptable_security.c
index 4646bf6d7d2b..81175c20ccbe 100644
--- a/net/ipv4/netfilter/iptable_security.c
+++ b/net/ipv4/netfilter/iptable_security.c
@@ -89,9 +89,9 @@ static int __init iptable_security_init(void)
static void __exit iptable_security_fini(void)
{
+ xt_unregister_template(&security_table);
unregister_pernet_subsys(&iptable_security_net_ops);
kfree(sectbl_ops);
- xt_unregister_template(&security_table);
}
module_init(iptable_security_init);
diff --git a/net/ipv6/netfilter/ip6table_filter.c b/net/ipv6/netfilter/ip6table_filter.c
index f05a9e4b2c67..cf561919bde8 100644
--- a/net/ipv6/netfilter/ip6table_filter.c
+++ b/net/ipv6/netfilter/ip6table_filter.c
@@ -100,8 +100,8 @@ static int __init ip6table_filter_init(void)
static void __exit ip6table_filter_fini(void)
{
- unregister_pernet_subsys(&ip6table_filter_net_ops);
xt_unregister_template(&packet_filter);
+ unregister_pernet_subsys(&ip6table_filter_net_ops);
kfree(filter_ops);
}
diff --git a/net/ipv6/netfilter/ip6table_mangle.c b/net/ipv6/netfilter/ip6table_mangle.c
index afa4a5703e43..1a758f2bc537 100644
--- a/net/ipv6/netfilter/ip6table_mangle.c
+++ b/net/ipv6/netfilter/ip6table_mangle.c
@@ -128,8 +128,8 @@ static int __init ip6table_mangle_init(void)
static void __exit ip6table_mangle_fini(void)
{
- unregister_pernet_subsys(&ip6table_mangle_net_ops);
xt_unregister_template(&packet_mangler);
+ unregister_pernet_subsys(&ip6table_mangle_net_ops);
kfree(mangle_ops);
}
diff --git a/net/ipv6/netfilter/ip6table_raw.c b/net/ipv6/netfilter/ip6table_raw.c
index 32d2da81c52a..923455921c1d 100644
--- a/net/ipv6/netfilter/ip6table_raw.c
+++ b/net/ipv6/netfilter/ip6table_raw.c
@@ -98,8 +98,8 @@ static int __init ip6table_raw_init(void)
static void __exit ip6table_raw_fini(void)
{
- unregister_pernet_subsys(&ip6table_raw_net_ops);
xt_unregister_template(&packet_raw);
+ unregister_pernet_subsys(&ip6table_raw_net_ops);
kfree(rawtable_ops);
}
diff --git a/net/ipv6/netfilter/ip6table_security.c b/net/ipv6/netfilter/ip6table_security.c
index 3dfd8d6ea4b9..c44834d93fc7 100644
--- a/net/ipv6/netfilter/ip6table_security.c
+++ b/net/ipv6/netfilter/ip6table_security.c
@@ -88,8 +88,8 @@ static int __init ip6table_security_init(void)
static void __exit ip6table_security_fini(void)
{
- unregister_pernet_subsys(&ip6table_security_net_ops);
xt_unregister_template(&security_table);
+ unregister_pernet_subsys(&ip6table_security_net_ops);
kfree(sectbl_ops);
}
--
2.53.0
next prev parent reply other threads:[~2026-05-06 10:07 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-05-06 10:07 [PATCH v3 nf 0/8] netfilter: xtables: fix module load and teardown races Florian Westphal
2026-05-06 10:07 ` [PATCH v3 nf 1/8] netfilter: x_tables: allow initial table replace without emitting audit log message Florian Westphal
2026-05-06 10:07 ` [PATCH v3 nf 2/8] netfilter: xtables: allocate hook ops while under mutex Florian Westphal
2026-05-06 10:07 ` [PATCH v3 nf 3/8] netfilter: x_tables: add and use xt_unregister_table_pre_exit Florian Westphal
2026-05-06 10:07 ` Florian Westphal [this message]
2026-05-06 10:07 ` [PATCH v3 nf 5/8] netfilter: x_tables: add and use xtables_unregister_table_exit Florian Westphal
2026-05-06 10:07 ` [PATCH v3 nf 6/8] netfilter: ebtables: move to two-stage removal scheme Florian Westphal
2026-05-06 10:07 ` [PATCH v3 nf 7/8] netfilter: ebtables: close dangling table module init race Florian Westphal
2026-05-06 10:07 ` [PATCH v3 nf 8/8] netfilter: x_tables: " Florian Westphal
2026-05-07 9:19 ` [PATCH v3 nf 9/8] netfilter: bridge: eb_tables: close " Florian Westphal
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