CVE-2026-74421drm/rockchip: dw_dp: Switch to drmm_kzalloc()

Official description

In the Linux kernel, the following vulnerability has been resolved: drm/rockchip: dw_dp: Switch to drmm_kzalloc() Driver makes use of drmm_encoder_init() to initialize the encoder and automatically handle the cleanup by registering drm_encoder_cleanup() with drmm_add_action(). However, the internal structure containing the encoder part gets allocated with devm_kzalloc(), which happens while component_bind_all() is being called from Rockchip DRM driver. The component framework further ensures it is deallocated as part of releasing all the resources claimed during bind, which is triggered from component_unbind_all(). When the reference to the DRM device gets eventually dropped via drm_dev_put() in rockchip_drm_unbind(), drmm_encoder_alloc_release() attempts to access the now released encoder structure, leading to use-after-free. Ensure driver's internal structure is still reachable on encoder cleanup by switching from a device-managed allocation to a drm-managed one.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/0d60b835bca42f0f790689dd47819ed881a92ccc
• https://git.kernel.org/stable/c/6b0b92d1110eccccbd5ba2949bd2b9fb6ea5fc12
• https://git.kernel.org/stable/c/ed9da8d23020352ad24c528db09b5acdd78b81fd