CVE-2026-98779drm/amdgpu: fix ACP MFD device leak on init failure

Official description

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: fix ACP MFD device leak on init failure acp_hw_init() registers ACP child devices with mfd_add_devices() before attaching them to the ACP power domain and initializing the hardware. If attaching a child to the power domain fails, or if the ACP reset or clock enable operation times out, the failure path frees only the source cell, resource, and platform-data allocations. The child platform devices already registered by mfd_add_devices() remain registered and are never released. Remove the children from the power domain and unregister the MFD devices on failures that occur after mfd_add_devices() succeeds. Keep mfd_add_devices() failures on the existing cleanup path since the MFD core already rolls back partially registered children itself. The issue was identified by a static analysis tool I developed and confirmed by manual review. (cherry picked from commit 63da68d6a2279ec945581c990c5a59a5ae8b5560)

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/385ad314f1c096aae71fff516214bb312a6047fb
• https://git.kernel.org/stable/c/7b7f770f48be77ce38e93216983dcdf1ea3a42ba
• https://git.kernel.org/stable/c/65ef6645982ccde16a7bc98d025eb80f5fab47f6
• https://git.kernel.org/stable/c/d700c26ed64bd3c26e4aa7679b9d5f3333c3747a
• https://git.kernel.org/stable/c/2b9a53940a2bc063ea4cd09ee49220a503a0170c
• https://git.kernel.org/stable/c/587469076e4ffb617f7ad1a0c4a13072a3e87113
• https://git.kernel.org/stable/c/abf854513bc19e6e24d45353ac99ec5627ee0acc
• https://git.kernel.org/stable/c/f0013046151b7467e62c471c1c83d63ea255799c