From 6eaf41e87a223ae6f8e7a28d6e78384ad7e407f8 Mon Sep 17 00:00:00 2001
From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Thu, 20 Jul 2023 09:17:21 +0200
Subject: [PATCH] netfilter: nf_tables: skip bound chain on rule flush
Git-commit: 6eaf41e87a223ae6f8e7a28d6e78384ad7e407f8
Patch-mainline: v6.5-rc3
References: bsc#1215095 CVE-2023-3777
Skip bound chain when flushing table rules, the rule that owns this
chain releases these objects.
Otherwise, the following warning is triggered:
WARNING: CPU: 2 PID: 1217 at net/netfilter/nf_tables_api.c:2013 nf_tables_chain_destroy+0x1f7/0x210 [nf_tables]
CPU: 2 PID: 1217 Comm: chain-flush Not tainted 6.1.39 #1
RIP: 0010:nf_tables_chain_destroy+0x1f7/0x210 [nf_tables]
Fixes: d0e2c7de92c7 ("netfilter: nf_tables: add NFT_CHAIN_BINDING")
Reported-by: Kevin Rich <kevinrich1337@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
net/netfilter/nf_tables_api.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 40bff6e2ea5d..b9a4d3fd1d34 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -4087,6 +4087,8 @@ static int nf_tables_delrule(struct sk_buff *skb, const struct nfnl_info *info,
list_for_each_entry(chain, &table->chains, list) {
if (!nft_is_active_next(net, chain))
continue;
+ if (nft_chain_is_bound(chain))
+ continue;
ctx.chain = chain;
err = nft_delrule_by_chain(&ctx);
--
2.16.4