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

[ Upstream commit d78d867dcea69c328db30df665be5be7d0148484 ]

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.

BUG=b/342563163,b/342563242
TEST=None
RELEASE_NOTE=Fixed CVE-2024-27019 and CVE-2024-27020 in the linux kernel.

cos-patch: security-moderate
Fixes: e50092404c1b ("netfilter: nf_tables: add stateful objects")
Change-Id: I12cf51401f43ef54e684cddf94891021545ad279
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/73075
Reviewed-by: Oleksandr Tymoshenko <ovt@google.com>
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
1 file changed