Subject: CVE-2024-40924: drm/i915/dpt: Make DPT object unshrinkable

From: Greg Kroah-Hartman <[email-masked]>

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

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

drm/i915/dpt: Make DPT object unshrinkable

In some scenarios, the DPT object gets shrunk but
the actual framebuffer did not and thus its still
there on the DPT's vm->bound_list. Then it tries to
rewrite the PTEs via a stale CPU mapping. This causes panic.

[vsyrjala: Add TODO comment]
(cherry picked from commit 51064d471c53dcc8eddd2333c3f1c1d9131ba36c)

The Linux kernel CVE team has assigned CVE-2024-40924 to this issue.

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

	Issue introduced in 6.0 with commit 0dc987b699ce and fixed in 6.1.95 with commit 327280149066
	Issue introduced in 6.0 with commit 0dc987b699ce and fixed in 6.6.35 with commit 7a9883be3b98
	Issue introduced in 6.0 with commit 0dc987b699ce and fixed in 6.9.6 with commit a2552020fb71
	Issue introduced in 6.0 with commit 0dc987b699ce and fixed in 6.10 with commit 43e2b37e2ab6

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-2024-40924
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/i915/gem/i915_gem_object.h

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/327280149066f0e5f2e50356b5823f76dabfe86e
	https://git.kernel.org/stable/c/7a9883be3b98673333eec65c4a21cc18e60292eb
	https://git.kernel.org/stable/c/a2552020fb714ff357182c3c179abfac2289f84d
	https://git.kernel.org/stable/c/43e2b37e2ab660c3565d4cff27922bc70e79c3f1