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

[Edward Adam Davis]

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 efea25eb56ce..3862fa6bb288 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -106,7 +106,8 @@ void hci_req_sync_complete(struct hci_dev *hdev, u8 result, u16 opcode,
 		hdev->req_result = result;
 		hdev->req_status = HCI_REQ_DONE;
 		if (skb) {
-			kfree_skb(hdev->req_skb);
+			if (hdev->req_skb)
+				kfree_skb(hdev->req_skb);
 			hdev->req_skb = skb_get(skb);
 		}
 		wake_up_interruptible(&hdev->req_wait_q);