HID: logitech: perform bounds checking on device_id early enough

device_index is a char type and the size of paired_dj_deivces is 7 elements, therefore proper bounds checking has to be applied to device_index before it is used. We are currently performing the bounds checking in logi_dj_recv_add_djhid_device(), which is too late, as malicious device could send REPORT_TYPE_NOTIF_DEVICE_UNPAIRED early enough and trigger the problem in one of the report forwarding functions called from logi_dj_raw_event(). Fix this by performing the check at the earliest possible ocasion in logi_dj_raw_event(). Cc: stable@vger.kernel.org Reported-by: Ben Hawkes <hawkes@google.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>

HID: logitech: perform bounds checking on device_id early enough
device_index is a char type and the size of paired_dj_deivces is 7 elements, therefore proper bounds checking has to be applied to device_index before it is used. We are currently performing the bounds checking in logi_dj_recv_add_djhid_device(), which is too late, as malicious device could send REPORT_TYPE_NOTIF_DEVICE_UNPAIRED early enough and trigger the problem in one of the report forwarding functions called from logi_dj_raw_event(). Fix this by performing the check at the earliest possible ocasion in logi_dj_raw_event(). Cc: stable@vger.kernel.org Reported-by: Ben Hawkes <hawkes@google.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Jiri Kosina · Eric Lee · Eric Lee · Eric Lee · Eric Lee · Eric Lee
1 parent 51217e6969
Showing 1 changed file with 6 additions and 7 deletions Side-by-side Diff
drivers/hid/hid-logitech-dj.c
@@ -238,13 +238,6 @@
 		return;
 	}
  
-	if ((dj_report->device_index < DJ_DEVICE_INDEX_MIN) ||
-	    (dj_report->device_index > DJ_DEVICE_INDEX_MAX)) {
-		dev_err(&djrcv_hdev->dev, "%s: invalid device index:%d\n",
-			__func__, dj_report->device_index);
-		return;
-	}
-
 	if (djrcv_dev->paired_dj_devices[dj_report->device_index]) {
 		/* The device is already known. No need to reallocate it. */
 		dbg_hid("%s: device is already known\n", __func__);
@@ -690,6 +683,12 @@
 	 * device (via hid_input_report() ) and return 1 so hid-core does not do
 	 * anything else with it.
 	 */
+	if ((dj_report->device_index < DJ_DEVICE_INDEX_MIN) ||
+	    (dj_report->device_index > DJ_DEVICE_INDEX_MAX)) {
+		dev_err(&hdev->dev, "%s: invalid device index:%d\n",
+				__func__, dj_report->device_index);
+		return false;
+	}
  
 	spin_lock_irqsave(&djrcv_dev->lock, flags);
 	if (dj_report->report_id == REPORT_ID_DJ_SHORT) {
...	...	@@ -238,13 +238,6 @@
238	238	return;
239	239	}
240	240
241		- if ((dj_report->device_index < DJ_DEVICE_INDEX_MIN) \|\|
242		- (dj_report->device_index > DJ_DEVICE_INDEX_MAX)) {
243		- dev_err(&djrcv_hdev->dev, "%s: invalid device index:%d\n",
244		- __func__, dj_report->device_index);
245		- return;
246		- }
247		-
248	241	if (djrcv_dev->paired_dj_devices[dj_report->device_index]) {
249	242	/* The device is already known. No need to reallocate it. */
250	243	dbg_hid("%s: device is already known\n", __func__);
...	...	@@ -690,6 +683,12 @@
690	683	* device (via hid_input_report() ) and return 1 so hid-core does not do
691	684	* anything else with it.
692	685	*/
	686	+ if ((dj_report->device_index < DJ_DEVICE_INDEX_MIN) \|\|
	687	+ (dj_report->device_index > DJ_DEVICE_INDEX_MAX)) {
	688	+ dev_err(&hdev->dev, "%s: invalid device index:%d\n",
	689	+ __func__, dj_report->device_index);
	690	+ return false;
	691	+ }
693	692
694	693	spin_lock_irqsave(&djrcv_dev->lock, flags);
695	694	if (dj_report->report_id == REPORT_ID_DJ_SHORT) {