CVE-2026-80728: Revert "drm/amdgpu: fix aperture mapping leak"

CVE-2026-80728: Revert "drm/amdgpu: fix aperture mapping leak"

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

Description
===========

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

Revert "drm/amdgpu: fix aperture mapping leak"

devres teardown is LIFO. The aperture devres node was registered after
the DRM device node, so devres_release_all() unmaps the aperture before
the DRM device release callback fires amdgpu_device_fini_sw(). IP
sw_fini callbacks (e.g. vcn_v4_0_sw_fini) write to fw_shared through a
pointer derived from aper_base_kaddr, causing a kernel page fault on
probe failure / rollback:

  BUG: unable to handle page fault ... PMD 0
  RIP: vcn_v4_0_sw_fini+0x7b/0x170 [amdgpu]
  Call Trace:
    amdgpu_device_fini_sw
    amdgpu_driver_release_kms
    devm_drm_dev_init_release
    devres_release_all

This reverts commit d871e99879cb5fd1fa798b006b4888887e63a17a.

(cherry picked from commit 336e0cd576817ac64a4b394ca2b3680029f3e37f)

The Linux kernel CVE team has assigned CVE-2026-80728 to this issue.


Affected and fixed versions
===========================

	Fixed in 6.6.152 with commit 7380f1bfe9d7ed3a4ca9d99a5c4df840fff9af2a
	Fixed in 6.12.104 with commit 96d26143882f9cb47dcc1f3dd4e26d047e53ab9b
	Fixed in 6.18.45 with commit a2e326c52c4bcecc033cd3ca2733fdbe30fbf55d
	Fixed in 7.1.9 with commit 496846a9411136eb9e86ad4f4e62d751bd1e1db5
	Fixed in 7.2 with commit b96c529cd2551b78316a4afa3237b2ed96ba03c8

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-80728
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
	drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/7380f1bfe9d7ed3a4ca9d99a5c4df840fff9af2a
	https://git.kernel.org/stable/c/96d26143882f9cb47dcc1f3dd4e26d047e53ab9b
	https://git.kernel.org/stable/c/a2e326c52c4bcecc033cd3ca2733fdbe30fbf55d
	https://git.kernel.org/stable/c/496846a9411136eb9e86ad4f4e62d751bd1e1db5
	https://git.kernel.org/stable/c/b96c529cd2551b78316a4afa3237b2ed96ba03c8