CVE-2024-56608

/// Technical description

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

drm/amd/display: Fix out-of-bounds access in 'dcn21_link_encoder_create'

An issue was identified in the dcn21_link_encoder_create function where

an out-of-bounds access could occur when the hpd_source index was used

to reference the link_enc_hpd_regs array. This array has a fixed size

and the index was not being checked against the array's bounds before

accessing it.

This fix adds a conditional check to ensure that the hpd_source index is

within the valid range of the link_enc_hpd_regs array. If the index is

out of bounds, the function now returns NULL to prevent undefined

behavior.

References:

[ 65.920507] ------------[ cut here ]------------

[ 65.920510] UBSAN: array-index-out-of-bounds in drivers/gpu/drm/amd/amdgpu/../display/dc/resource/dcn21/dcn21_resource.c:1312:29

[ 65.920519] index 7 is out of range for type 'dcn10_link_enc_hpd_registers [5]'

[ 65.920523] CPU: 3 PID: 1178 Comm: modprobe Tainted: G

/// 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