Received-SPF: pass (google.com: domain of linux-bluetooth-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Min Li <lm0963hack@gmail.com>
To:     luiz.dentz@gmail.com
Cc:     marcel@holtmann.org, johan.hedberg@gmail.com,
        linux-bluetooth@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] Bluetooth: HCI: fix use-after-free in hci_remove_ltk/hci_remove_irk
Date:   Tue, 23 May 2023 19:56:37 +0800
Message-Id: <20230523115637.14541-1-lm0963hack@gmail.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

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@gmail.com>
---
 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