Ksawlii/kernel_samsung_a53x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

netfilter: nf_tables: Fix potential data-race in __nft_obj_type_get()

Browse source 
commit d78d867dcea69c328db30df665be5be7d0148484 upstream.

nft_unregister_obj() can concurrent with __nft_obj_type_get(),
and there is not any protection when iterate over nf_tables_objects
list in __nft_obj_type_get(). Therefore, there is potential data-race
of nf_tables_objects list entry.

Use list_for_each_entry_rcu() to iterate over nf_tables_objects
list in __nft_obj_type_get(), and use rcu_read_lock() in the caller
nft_obj_type_get() to protect the entire type query process.

Fixes: e50092404c1b ("netfilter: nf_tables: add stateful objects")
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Kuntal Nayak <kuntal.nayak@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ziyang Xuan 2024-04-07 14:56:05 +08:00 • committed by Ksawlii
parent 863ae415c0
commit 859cbb14b1
1 changed files with 6 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
net/netfilter/nf_tables_api.c
View file

@ -6238,7 +6238,7 @@ static const struct nft_object_type *__nft_obj_type_get(u32 objtype, u8 family)
{
const struct nft_object_type *type;
list_for_each_entry(type, &nf_tables_objects, list) {
list_for_each_entry_rcu(type, &nf_tables_objects, list) {
if (type->family != NFPROTO_UNSPEC &&
type->family != family)
continue;
@ -6254,9 +6254,13 @@ nft_obj_type_get(struct net *net, u32 objtype, u8 family)
{
const struct nft_object_type *type;
rcu_read_lock();
type = __nft_obj_type_get(objtype, family);
if (type != NULL && try_module_get(type->owner))
if (type != NULL && try_module_get(type->owner)) {
rcu_read_unlock();
return type;
}
rcu_read_unlock();
lockdep_nfnl_nft_mutex_not_held();
#ifdef CONFIG_MODULES