The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x 994209ddf4f430946f6247616b2e33d179243769 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2024040556-dexterity-handwrite-98fd@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 994209ddf4f430946f6247616b2e33d179243769 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso pablo@netfilter.org Date: Mon, 1 Apr 2024 00:33:02 +0200 Subject: [PATCH] netfilter: nf_tables: reject new basechain after table flag update

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@netfilter.org

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 17bf53cd0e84..1eb51bf24fc2 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -2449,6 +2449,9 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask, 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;