CVE-2026-43337

/// Technical description

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

drm/amd/display: Fix NULL pointer dereference in dcn401_init_hw()

dcn401_init_hw() assumes that update_bw_bounding_box() is valid when

entering the update path. However, the existing condition:

((!fams2_enable && update_bw_bounding_box) || freq_changed)

does not guarantee this, as the freq_changed branch can evaluate to true

independently of the callback pointer.

This can result in calling update_bw_bounding_box() when it is NULL.

Fix this by separating the update condition from the pointer checks and

ensuring the callback, dc->clk_mgr, and bw_params are validated before

use.

Fixes the below:

../dc/hwss/dcn401/dcn401_hwseq.c:367 dcn401_init_hw() error: we previously assumed 'dc->res_pool->funcs->update_bw_bounding_box' could be null (see line 362)

(cherry picked from commit 86117c5ab42f21562fedb0a64bffea3ee5fcd477)

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References