[PATCH] Bluetooth: HCI: fix use-after-free in hci_remove_ltk/hci_remove_irk

From: Min Li
Date: Tue May 23 2023 - 21:30:35 EST


Similar to commit 0f7d9b31ce7a ("netfilter: nf_tables: fix use-after-free
in nft_set_catchall_destroy()"). We can not access k after kfree_rcu()
call.

Signed-off-by: Min Li <lm0963hack@xxxxxxxxx>
---
net/bluetooth/hci_core.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index a856b1051d35..0164b56de12d 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -1416,10 +1416,10 @@ int hci_remove_link_key(struct hci_dev *hdev, bdaddr_t *bdaddr)

int hci_remove_ltk(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 bdaddr_type)
{
- struct smp_ltk *k;
+ struct smp_ltk *k, *tmp;
int removed = 0;

- list_for_each_entry_rcu(k, &hdev->long_term_keys, list) {
+ list_for_each_entry_safe(k, tmp, &hdev->long_term_keys, list) {
if (bacmp(bdaddr, &k->bdaddr) || k->bdaddr_type != bdaddr_type)
continue;

@@ -1435,9 +1435,9 @@ int hci_remove_ltk(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 bdaddr_type)

void hci_remove_irk(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 addr_type)
{
- struct smp_irk *k;
+ struct smp_irk *k, *tmp;

- list_for_each_entry_rcu(k, &hdev->identity_resolving_keys, list) {
+ list_for_each_entry_safe(k, tmp, &hdev->identity_resolving_keys, list) {
if (bacmp(bdaddr, &k->bdaddr) || k->addr_type != addr_type)
continue;

--
2.34.1