// For flags

CVE-2024-26874

drm/mediatek: Fix a null pointer crash in mtk_drm_crtc_finish_page_flip

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*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track
*SSVC
Descriptions

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

drm/mediatek: Fix a null pointer crash in mtk_drm_crtc_finish_page_flip

It's possible that mtk_crtc->event is NULL in
mtk_drm_crtc_finish_page_flip().

pending_needs_vblank value is set by mtk_crtc->event, but in
mtk_drm_crtc_atomic_flush(), it's is not guarded by the same
lock in mtk_drm_finish_page_flip(), thus a race condition happens.

Consider the following case:

CPU1 CPU2
step 1:
mtk_drm_crtc_atomic_begin()
mtk_crtc->event is not null,
step 1:
mtk_drm_crtc_atomic_flush:
mtk_drm_crtc_update_config(
!!mtk_crtc->event)
step 2:
mtk_crtc_ddp_irq ->
mtk_drm_finish_page_flip:
lock
mtk_crtc->event set to null,
pending_needs_vblank set to false
unlock
pending_needs_vblank set to true,

step 2:
mtk_crtc_ddp_irq ->
mtk_drm_finish_page_flip called again,
pending_needs_vblank is still true
//null pointer

Instead of guarding the entire mtk_drm_crtc_atomic_flush(), it's more
efficient to just check if mtk_crtc->event is null before use.

En el kernel de Linux, se resolvió la siguiente vulnerabilidad: drm/mediatek: corrige un fallo del puntero nulo en mtk_drm_crtc_finish_page_flip Es posible que mtk_crtc->event sea NULL en mtk_drm_crtc_finish_page_flip(). El valor pendiente_needs_vblank lo establece mtk_crtc->event, pero en mtk_drm_crtc_atomic_flush(), no está protegido por el mismo bloqueo en mtk_drm_finish_page_flip(), por lo que ocurre una condición de carrera. Considere el siguiente caso: CPU1 CPU2 paso 1: mtk_drm_crtc_atomic_begin() mtk_crtc->event is not null, paso 1: mtk_drm_crtc_atomic_flush: mtk_drm_crtc_update_config( !!mtk_crtc->event) paso 2: mtk_crtc_ddp_irq -> mtk_drm_finish _page_flip: bloquear mtk_crtc->evento establecido en nulo, pendiente_needs_vblank configurado en falso desbloqueo pendiente_needs_vblank configurado en verdadero, paso 2: mtk_crtc_ddp_irq -> mtk_drm_finish_page_flip llamado nuevamente, pendiente_needs_vblank sigue siendo verdadero //puntero nulo En lugar de proteger todo el mtk_drm_crtc_atomic_flush(), es más eficiente simplemente verificar si mtk_crtc->even t es nulo antes de su uso.

*Credits: N/A
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* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-02-19 CVE Reserved
  • 2024-04-17 CVE Published
  • 2024-04-18 EPSS Updated
  • 2024-12-19 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 4.7 < 4.19.311
Search vendor "Linux" for product "Linux Kernel" and version " >= 4.7 < 4.19.311"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 4.7 < 5.4.273
Search vendor "Linux" for product "Linux Kernel" and version " >= 4.7 < 5.4.273"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 4.7 < 5.10.214
Search vendor "Linux" for product "Linux Kernel" and version " >= 4.7 < 5.10.214"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 4.7 < 5.15.153
Search vendor "Linux" for product "Linux Kernel" and version " >= 4.7 < 5.15.153"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 4.7 < 6.1.83
Search vendor "Linux" for product "Linux Kernel" and version " >= 4.7 < 6.1.83"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 4.7 < 6.6.23
Search vendor "Linux" for product "Linux Kernel" and version " >= 4.7 < 6.6.23"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 4.7 < 6.7.11
Search vendor "Linux" for product "Linux Kernel" and version " >= 4.7 < 6.7.11"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 4.7 < 6.8.2
Search vendor "Linux" for product "Linux Kernel" and version " >= 4.7 < 6.8.2"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 4.7 < 6.9
Search vendor "Linux" for product "Linux Kernel" and version " >= 4.7 < 6.9"
en
Affected