cdrom: Fix info leak/OOB read in cdrom_ioctl_drive_status

Like d88b6d0: "cdrom: information leak in cdrom_ioctl_media_changed()" There is another cast from unsigned long to int which causes a bounds check to fail with specially crafted input. The value is then used as an index in the slot array in cdrom_slot_status(). Signed-off-by: Scott Bauer <[email protected]> Signed-off-by: Scott Bauer <[email protected]> Cc: [email protected] Signed-off-by: Jens Axboe <[email protected]>
josf · Aug 29, 2018 · 8f3fafc · 8f3fafc
1 parent db19395
commit 8f3fafc
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c
@@ -2546,7 +2546,7 @@ static int cdrom_ioctl_drive_status(struct cdrom_device_info *cdi,
 	if (!CDROM_CAN(CDC_SELECT_DISC) ||
 	    (arg == CDSL_CURRENT || arg == CDSL_NONE))
 		return cdi->ops->drive_status(cdi, CDSL_CURRENT);
-	if (((int)arg >= cdi->capacity))
+	if (arg >= cdi->capacity)
 		return -EINVAL;
 	return cdrom_slot_status(cdi, arg);
 }