This is a note to let you know that I've just added the patch titled
netfilter: nf_tables: reject new basechain after table flag update
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
netfilter-nf_tables-reject-new-basechain-after-table-flag-update.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 994209ddf4f430946f6247616b2e33d179243769 Mon Sep 17 00:00:00 2001
From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Date: Mon, 1 Apr 2024 00:33:02 +0200
Subject: netfilter: nf_tables: reject new basechain after table flag update
From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
commit 994209ddf4f430946f6247616b2e33d179243769 upstream.
When dormant flag is toggled, hooks are disabled in the commit phase by
iterating over current chains in table (existing and new).
The following configuration allows for an inconsistent state:
add table x
add chain x y { type filter hook input priority 0; }
add table x { flags dormant; }
add chain x w { type filter hook input priority 1; }
which triggers the following warning when trying to unregister chain w
which is already unregistered.
[ 127.322252] WARNING: CPU: 7 PID: 1211 at net/netfilter/core.c:50 1 __nf_unregister_net_hook+0x21a/0x260
[...]
[ 127.322519] Call Trace:
[ 127.322521] <TASK>
[ 127.322524] ? __warn+0x9f/0x1a0
[ 127.322531] ? __nf_unregister_net_hook+0x21a/0x260
[ 127.322537] ? report_bug+0x1b1/0x1e0
[ 127.322545] ? handle_bug+0x3c/0x70
[ 127.322552] ? exc_invalid_op+0x17/0x40
[ 127.322556] ? asm_exc_invalid_op+0x1a/0x20
[ 127.322563] ? kasan_save_free_info+0x3b/0x60
[ 127.322570] ? __nf_unregister_net_hook+0x6a/0x260
[ 127.322577] ? __nf_unregister_net_hook+0x21a/0x260
[ 127.322583] ? __nf_unregister_net_hook+0x6a/0x260
[ 127.322590] ? __nf_tables_unregister_hook+0x8a/0xe0 [nf_tables]
[ 127.322655] nft_table_disable+0x75/0xf0 [nf_tables]
[ 127.322717] nf_tables_commit+0x2571/0x2620 [nf_tables]
Fixes: 179d9ba5559a ("netfilter: nf_tables: fix table flag updates")
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/netfilter/nf_tables_api.c | 3 +++
1 file changed, 3 insertions(+)
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -2372,6 +2372,9 @@ static int nf_tables_addchain(struct nft
struct nft_stats __percpu *stats = NULL;
struct nft_chain_hook hook;
+ if (table->flags & __NFT_TABLE_F_UPDATE)
+ return -EINVAL;
+
if (flags & NFT_CHAIN_BINDING)
return -EOPNOTSUPP;
Patches currently in stable-queue which might be from pablo@xxxxxxxxxxxxx are
queue-6.1/netfilter-nf_tables-reject-new-basechain-after-table-flag-update.patch
queue-6.1/netfilter-nf_tables-flush-pending-destroy-work-before-exit_net-release.patch
queue-6.1/netfilter-validate-user-input-for-expected-length.patch
queue-6.1/netfilter-nf_tables-fix-potential-data-race-in-__nft_flowtable_type_get.patch
