Re: [syzbot] [bluetooth?] KASAN: invalid-free in hci_req_sync_complete

Edward Adam Davis
2024-06-24T12:13:38Z

please test db free in hci_req_sync_complete

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 2ccbdf43d5e7

diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index 3862fa6bb288..4d5807fff946 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -121,6 +121,7 @@ int __hci_req_sync(struct hci_dev *hdev, int (*func)(struct hci_request *req,
{
struct hci_request req;
int err = 0;
+ struct sk_buff *req_skb;

bt_dev_dbg(hdev, "start");

@@ -182,8 +183,9 @@ int __hci_req_sync(struct hci_dev *hdev, int (*func)(struct hci_request *req,
break;
}

- kfree_skb(hdev->req_skb);
+ req_skb = hdev->req_skb;
hdev->req_skb = NULL;
+ kfree_skb(req_skb);
hdev->req_status = hdev->req_result = 0;

bt_dev_dbg(hdev, "end: err %d", err);