From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Tue, 17 Sep 2024 21:07:46 +0000 (+0200)
Subject: netfilter: nf_tables: use rcu chain hook list iterator from netlink dump path
X-Git-Tag: v6.6.54~159
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=da2bb8e177a46f23ca5a0586173b2240fef86078;p=thirdparty%2Fkernel%2Fstable.git

netfilter: nf_tables: use rcu chain hook list iterator from netlink dump path

[ Upstream commit 4ffcf5ca81c3b83180473eb0d3c010a1a7c6c4de ]

Lockless iteration over hook list is possible from netlink dump path,
use rcu variant to iterate over the hook list as is done with flowtable
hooks.

Fixes: b9703ed44ffb ("netfilter: nf_tables: support for adding new devices to an existing netdev chain")
Reported-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 935e953b8e1bf..da7fd3919ce48 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -1778,7 +1778,7 @@ static int nft_dump_basechain_hook(struct sk_buff *skb, int family,
 		if (!hook_list)
 			hook_list = &basechain->hook_list;
 
-		list_for_each_entry(hook, hook_list, list) {
+		list_for_each_entry_rcu(hook, hook_list, list) {
 			if (!first)
 				first = hook;