You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
113 lines
3.6 KiB
113 lines
3.6 KiB
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
|
|
From: Javier Martinez Canillas <javierm@redhat.com>
|
|
Date: Fri, 11 Dec 2020 19:19:21 +0100
|
|
Subject: [PATCH] usb: Avoid possible out-of-bound accesses caused by malicious
|
|
devices
|
|
|
|
The maximum number of configurations and interfaces are fixed but there is
|
|
no out-of-bound checking to prevent a malicious USB device to report large
|
|
values for these and cause accesses outside the arrays' memory.
|
|
|
|
Fixes: CVE-2020-25647
|
|
|
|
Reported-by: Joseph Tartaro (IOActive)
|
|
Reported-by: Ilja Van Sprundel <ivansprundel@ioactive.com>
|
|
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
|
|
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
|
|
---
|
|
grub-core/bus/usb/usb.c | 15 ++++++++++++---
|
|
include/grub/usb.h | 10 +++++++---
|
|
2 files changed, 19 insertions(+), 6 deletions(-)
|
|
|
|
diff --git a/grub-core/bus/usb/usb.c b/grub-core/bus/usb/usb.c
|
|
index 8da5e4c74..7cb3cc230 100644
|
|
--- a/grub-core/bus/usb/usb.c
|
|
+++ b/grub-core/bus/usb/usb.c
|
|
@@ -75,6 +75,9 @@ grub_usb_controller_iterate (grub_usb_controller_iterate_hook_t hook,
|
|
grub_usb_err_t
|
|
grub_usb_clear_halt (grub_usb_device_t dev, int endpoint)
|
|
{
|
|
+ if (endpoint >= GRUB_USB_MAX_TOGGLE)
|
|
+ return GRUB_USB_ERR_BADDEVICE;
|
|
+
|
|
dev->toggle[endpoint] = 0;
|
|
return grub_usb_control_msg (dev, (GRUB_USB_REQTYPE_OUT
|
|
| GRUB_USB_REQTYPE_STANDARD
|
|
@@ -134,10 +137,10 @@ grub_usb_device_initialize (grub_usb_device_t dev)
|
|
return err;
|
|
descdev = &dev->descdev;
|
|
|
|
- for (i = 0; i < 8; i++)
|
|
+ for (i = 0; i < GRUB_USB_MAX_CONF; i++)
|
|
dev->config[i].descconf = NULL;
|
|
|
|
- if (descdev->configcnt == 0)
|
|
+ if (descdev->configcnt == 0 || descdev->configcnt > GRUB_USB_MAX_CONF)
|
|
{
|
|
err = GRUB_USB_ERR_BADDEVICE;
|
|
goto fail;
|
|
@@ -172,6 +175,12 @@ grub_usb_device_initialize (grub_usb_device_t dev)
|
|
/* Skip the configuration descriptor. */
|
|
pos = dev->config[i].descconf->length;
|
|
|
|
+ if (dev->config[i].descconf->numif > GRUB_USB_MAX_IF)
|
|
+ {
|
|
+ err = GRUB_USB_ERR_BADDEVICE;
|
|
+ goto fail;
|
|
+ }
|
|
+
|
|
/* Read all interfaces. */
|
|
for (currif = 0; currif < dev->config[i].descconf->numif; currif++)
|
|
{
|
|
@@ -217,7 +226,7 @@ grub_usb_device_initialize (grub_usb_device_t dev)
|
|
|
|
fail:
|
|
|
|
- for (i = 0; i < 8; i++)
|
|
+ for (i = 0; i < GRUB_USB_MAX_CONF; i++)
|
|
grub_free (dev->config[i].descconf);
|
|
|
|
return err;
|
|
diff --git a/include/grub/usb.h b/include/grub/usb.h
|
|
index 512ae1dd0..6475c552f 100644
|
|
--- a/include/grub/usb.h
|
|
+++ b/include/grub/usb.h
|
|
@@ -23,6 +23,10 @@
|
|
#include <grub/usbdesc.h>
|
|
#include <grub/usbtrans.h>
|
|
|
|
+#define GRUB_USB_MAX_CONF 8
|
|
+#define GRUB_USB_MAX_IF 32
|
|
+#define GRUB_USB_MAX_TOGGLE 256
|
|
+
|
|
typedef struct grub_usb_device *grub_usb_device_t;
|
|
typedef struct grub_usb_controller *grub_usb_controller_t;
|
|
typedef struct grub_usb_controller_dev *grub_usb_controller_dev_t;
|
|
@@ -167,7 +171,7 @@ struct grub_usb_configuration
|
|
struct grub_usb_desc_config *descconf;
|
|
|
|
/* Interfaces associated to this configuration. */
|
|
- struct grub_usb_interface interf[32];
|
|
+ struct grub_usb_interface interf[GRUB_USB_MAX_IF];
|
|
};
|
|
|
|
struct grub_usb_hub_port
|
|
@@ -191,7 +195,7 @@ struct grub_usb_device
|
|
struct grub_usb_controller controller;
|
|
|
|
/* Device configurations (after opening the device). */
|
|
- struct grub_usb_configuration config[8];
|
|
+ struct grub_usb_configuration config[GRUB_USB_MAX_CONF];
|
|
|
|
/* Device address. */
|
|
int addr;
|
|
@@ -203,7 +207,7 @@ struct grub_usb_device
|
|
int initialized;
|
|
|
|
/* Data toggle values (used for bulk transfers only). */
|
|
- int toggle[256];
|
|
+ int toggle[GRUB_USB_MAX_TOGGLE];
|
|
|
|
/* Used by libusb wrapper. Schedulded for removal. */
|
|
void *data;
|