In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix NULL pointer dereference in dcn401inithw()
dcn401inithw() assumes that updatebwbounding_box() is valid when entering the update path. However, the existing condition:
((!fams2enable && updatebwboundingbox) || 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 updatebwbounding_box() when it is NULL.
Fix this by separating the update condition from the pointer checks and ensuring the callback, dc->clkmgr, and bwparams are validated before use.
Fixes the below: ../dc/hwss/dcn401/dcn401hwseq.c:367 dcn401inithw() error: we previously assumed 'dc->respool->funcs->updatebwbounding_box' could be null (see line 362)
(cherry picked from commit 86117c5ab42f21562fedb0a64bffea3ee5fcd477)
{
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43337.json",
"cna_assigner": "Linux"
}