CVE-2026-43337

Summary

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)

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxca0fb243c3bb53dbbd71d16c76f319bf923ee3d4 < 10c13c111d0d7f8e101c742feff264fc98e3f9f7affected
LinuxLinuxca0fb243c3bb53dbbd71d16c76f319bf923ee3d4 < 2d4a6f0702c5211e0be8b688c5fc24f082ec74d6affected
LinuxLinuxca0fb243c3bb53dbbd71d16c76f319bf923ee3d4 < e927b36ae18b66b49219eaa9f46edc7b4fdbb25eaffected
LinuxLinuxe13689793b9c0e7b5749954e77f5f85e68fe7138affected
LinuxLinux6.11.3 < 6.12affected
LinuxLinux6.12affected
LinuxLinux0 < 6.12unaffected
LinuxLinux6.18.22 <= 6.18.*unaffected
LinuxLinux6.19.12 <= 6.19.*unaffected
LinuxLinux7.0 <= *unaffected

Weaknesses

References