[PATCH 4.19 10/48] Bluetooth: Prevent out-of-bounds read in hci_inquiry_result_with_rssi_evt()

[Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>]

From: Peilin Ye <yepeilin.cs@xxxxxxxxx>

commit 629b49c848ee71244203934347bd7730b0ddee8d upstream.

Check `num_rsp` before using it as for-loop counter. Add `unlock` label.

Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Peilin Ye <yepeilin.cs@xxxxxxxxx>
Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 net/bluetooth/hci_event.c |    7 +++++++
 1 file changed, 7 insertions(+)

--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -3948,6 +3948,9 @@ static void hci_inquiry_result_with_rssi
 		struct inquiry_info_with_rssi_and_pscan_mode *info;
 		info = (void *) (skb->data + 1);
 
+		if (skb->len < num_rsp * sizeof(*info) + 1)
+			goto unlock;
+
 		for (; num_rsp; num_rsp--, info++) {
 			u32 flags;
 
@@ -3969,6 +3972,9 @@ static void hci_inquiry_result_with_rssi
 	} else {
 		struct inquiry_info_with_rssi *info = (void *) (skb->data + 1);
 
+		if (skb->len < num_rsp * sizeof(*info) + 1)
+			goto unlock;
+
 		for (; num_rsp; num_rsp--, info++) {
 			u32 flags;
 
@@ -3989,6 +3995,7 @@ static void hci_inquiry_result_with_rssi
 		}
 	}
 
+unlock:
 	hci_dev_unlock(hdev);
 }