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 5.4-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.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit a1e06b0359c85296e6b0691f236a342d80e66ec3
Author: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Date: Mon Apr 8 23:21:38 2024 +0200
netfilter: nf_tables: reject new basechain after table flag update
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: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 7c98536e9eae2..f4821d64c2fd8 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -1805,6 +1805,9 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask,
struct nft_chain_hook hook;
struct nf_hook_ops *ops;
+ if (table->flags & __NFT_TABLE_F_UPDATE)
+ return -EINVAL;
+
err = nft_chain_parse_hook(net, nla, &hook, family, true);
if (err < 0)
return err;
