CVE-2024-26874

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux119f5173628aa7a0c3cf9db83460d40709e8241d < accdac6b71d5a2b84040c3d2234f53a60edc398eaffected
LinuxLinux119f5173628aa7a0c3cf9db83460d40709e8241d < dfde84cc6c589f2a9f820f12426d97365670b731affected
LinuxLinux119f5173628aa7a0c3cf9db83460d40709e8241d < 4688be96d20ffa49d2186523ee84f475f316fd49affected
LinuxLinux119f5173628aa7a0c3cf9db83460d40709e8241d < 9beec711a17245b853d64488fd5b739031612340affected
LinuxLinux119f5173628aa7a0c3cf9db83460d40709e8241d < d2bd30c710475b2e29288827d2c91f9e6e2b91d7affected
LinuxLinux119f5173628aa7a0c3cf9db83460d40709e8241d < a3dd12b64ae8373a41a216a0b621df224210860aaffected
LinuxLinux119f5173628aa7a0c3cf9db83460d40709e8241d < 9acee29a38b4d4b70f1f583e5ef9a245db4db710affected
LinuxLinux119f5173628aa7a0c3cf9db83460d40709e8241d < 3fc88b246a2fc16014e374040fc15af1d3752535affected
LinuxLinux119f5173628aa7a0c3cf9db83460d40709e8241d < c958e86e9cc1b48cac004a6e245154dfba8e163baffected
LinuxLinux4.7affected
LinuxLinux0 < 4.7unaffected
LinuxLinux4.19.311 <= 4.19.*unaffected
LinuxLinux5.4.273 <= 5.4.*unaffected
LinuxLinux5.10.214 <= 5.10.*unaffected
LinuxLinux5.15.153 <= 5.15.*unaffected
LinuxLinux6.1.83 <= 6.1.*unaffected
LinuxLinux6.6.23 <= 6.6.*unaffected
LinuxLinux6.7.11 <= 6.7.*unaffected
LinuxLinux6.8.2 <= 6.8.*unaffected
LinuxLinux6.9 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

CVE Program Container

Additional References

References