This is a note to let you know that I've just added the patch titled netfilter: nf_tables: Keep deleted flowtable hooks until after RCU to the 5.15-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-keep-deleted-flowtable-hooks-unt.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit aac93a2e12724aad10b346292d81e25ca4edcd20 Author: Phil Sutter <phil@xxxxxx> Date: Thu Sep 12 14:21:33 2024 +0200 netfilter: nf_tables: Keep deleted flowtable hooks until after RCU [ Upstream commit 642c89c475419b4d0c0d90e29d9c1a0e4351f379 ] Documentation of list_del_rcu() warns callers to not immediately free the deleted list item. While it seems not necessary to use the RCU-variant of list_del() here in the first place, doing so seems to require calling kfree_rcu() on the deleted item as well. Fixes: 3f0465a9ef02 ("netfilter: nf_tables: dynamically allocate hooks per net_device in flowtables") Signed-off-by: Phil Sutter <phil@xxxxxx> 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 f493f4351ca52..71a486d9fd76a 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -8434,7 +8434,7 @@ static void nf_tables_flowtable_destroy(struct nft_flowtable *flowtable) flowtable->data.type->setup(&flowtable->data, hook->ops.dev, FLOW_BLOCK_UNBIND); list_del_rcu(&hook->list); - kfree(hook); + kfree_rcu(hook, rcu); } kfree(flowtable->name); module_put(flowtable->data.type->owner);