---
id: CVE-2026-31562
title: 'drm/mediatek: dsi: Store driver data before invoking mipi_dsi_host_register'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  drm/mediatek: dsi: Store driver data before invoking mipi_dsi_host_register

  The call to mipi_dsi_host_register triggers a callback to mtk_dsi_bind,
  which uses dev_get_…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= e4732b590a77318dff134612b013d66d2448ab20 <
    57b4864ca02f76d7debe8ce14c912335aef16055
  - >-
    Linux >= e4732b590a77318dff134612b013d66d2448ab20 <
    9a709b7e36324dfc1e6728eb81405470b7ae84e5
  - >-
    Linux >= e4732b590a77318dff134612b013d66d2448ab20 <
    df03f5ac1eae7c5a2c01846e3e64dfc2870eec6b
  - >-
    Linux >= e4732b590a77318dff134612b013d66d2448ab20 <
    4cfdfeb6ac06079f92fccd977fa742d6c5b8dd3a
  - Linux 6.9
published: '2026-04-24'
updated: '2026-10-21'
sourceUpdated: '2026-10-21T12:39:29.897Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-31562'
references:
  - url: 'https://git.kernel.org/stable/c/57b4864ca02f76d7debe8ce14c912335aef16055'
  - url: 'https://git.kernel.org/stable/c/9a709b7e36324dfc1e6728eb81405470b7ae84e5'
  - url: 'https://git.kernel.org/stable/c/df03f5ac1eae7c5a2c01846e3e64dfc2870eec6b'
  - url: 'https://git.kernel.org/stable/c/4cfdfeb6ac06079f92fccd977fa742d6c5b8dd3a'
tags:
  - cve.org
epss: 0.0016
epssPercentile: 0.0479
ingestedAt: '2026-10-21T12:48:53.663Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

drm/mediatek: dsi: Store driver data before invoking mipi_dsi_host_register

The call to mipi_dsi_host_register triggers a callback to mtk_dsi_bind,
which uses dev_get_drvdata to retrieve the mtk_dsi struct, so this
structure needs to be stored inside the driver data before invoking it.

As drvdata is currently uninitialized it leads to a crash when
registering the DSI DRM encoder right after acquiring
the mode_config.idr_mutex, blocking all subsequent DRM operations.

Fixes the following crash during mediatek-drm probe (tested on Xiaomi
Smart Clock x04g):

Unable to handle kernel NULL pointer dereference at virtual address
 0000000000000040
[...]
Modules linked in: mediatek_drm(+) drm_display_helper cec drm_client_lib
 drm_dma_helper drm_kms_helper panel_simple
[...]
Call trace:
 drm_mode_object_add+0x58/0x98 (P)
 __drm_encoder_init+0x48/0x140
 drm_encoder_init+0x6c/0xa0
 drm_simple_encoder_init+0x20/0x34 [drm_kms_helper]
 mtk_dsi_bind+0x34/0x13c [mediatek_drm]
 component_bind_all+0x120/0x280
 mtk_drm_bind+0x284/0x67c [mediatek_drm]
 try_to_bring_up_aggregate_device+0x23c/0x320
 __component_add+0xa4/0x198
 component_add+0x14/0x20
 mtk_dsi_host_attach+0x78/0x100 [mediatek_drm]
 mipi_dsi_attach+0x2c/0x50
 panel_simple_dsi_probe+0x4c/0x9c [panel_simple]
 mipi_dsi_drv_probe+0x1c/0x28
 really_probe+0xc0/0x3dc
 __driver_probe_device+0x80/0x160
 driver_probe_device+0x40/0x120
 __device_attach_driver+0xbc/0x17c
 bus_for_each_drv+0x88/0xf0
 __device_attach+0x9c/0x1cc
 device_initial_probe+0x54/0x60
 bus_probe_device+0x34/0xa0
 device_add+0x5b0/0x800
 mipi_dsi_device_register_full+0xdc/0x16c
 mipi_dsi_host_register+0xc4/0x17c
 mtk_dsi_probe+0x10c/0x260 [mediatek_drm]
 platform_probe+0x5c/0xa4
 really_probe+0xc0/0x3dc
 __driver_probe_device+0x80/0x160
 driver_probe_device+0x40/0x120
 __driver_attach+0xc8/0x1f8
 bus_for_each_dev+0x7c/0xe0
 driver_attach+0x24/0x30
 bus_add_driver+0x11c/0x240
 driver_register+0x68/0x130
 __platform_register_drivers+0x64/0x160
 mtk_drm_init+0x24/0x1000 [mediatek_drm]
 do_one_initcall+0x60/0x1d0
 do_init_module+0x54/0x240
 load_module+0x1838/0x1dc0
 init_module_from_file+0xd8/0xf0
 __arm64_sys_finit_module+0x1b4/0x428
 invoke_syscall.constprop.0+0x48/0xc8
 do_el0_svc+0x3c/0xb8
 el0_svc+0x34/0xe8
 el0t_64_sync_handler+0xa0/0xe4
 el0t_64_sync+0x198/0x19c
Code: 52800022 941004ab 2a0003f3 37f80040 (29005a80)

## Affected

- `Linux >= e4732b590a77318dff134612b013d66d2448ab20 < 57b4864ca02f76d7debe8ce14c912335aef16055`
- `Linux >= e4732b590a77318dff134612b013d66d2448ab20 < 9a709b7e36324dfc1e6728eb81405470b7ae84e5`
- `Linux >= e4732b590a77318dff134612b013d66d2448ab20 < df03f5ac1eae7c5a2c01846e3e64dfc2870eec6b`
- `Linux >= e4732b590a77318dff134612b013d66d2448ab20 < 4cfdfeb6ac06079f92fccd977fa742d6c5b8dd3a`
- `Linux 6.9`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.