CVE-2026-93183: drm/lima: call drm_mm_init() with a valid allocation range

CVE-2026-93183: drm/lima: call drm_mm_init() with a valid allocation range

[Greg Kroah-Hartman]

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

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

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

drm/lima: call drm_mm_init() with a valid allocation range

lima_vm_create() is currently run before va_start and va_end are set up,
meaning they are both 0. lima_vm_create() runs drm_mm_init() with them
as arguments for the allocator, and if DRM_DEBUG_MM is enabled the
DRM_MM_BUG_ON check in drm_mm_init then fires, as seen here on
exynos4412-odroid-u2:

[    1.736297] ------------[ cut here ]------------
[    1.740370] kernel BUG at drivers/gpu/drm/drm_mm.c:931!
[    1.745574] Internal error: Oops - BUG: 0 [#1] SMP ARM
[    1.750697] Modules linked in:
[    1.753734] CPU: 0 UID: 0 PID: 41 Comm: kworker/u16:1 Not tainted 7.0.10-postmarketos-exynos4 #11 PREEMPT
[    1.763372] Hardware name: Samsung Exynos (Flattened Device Tree)
[    1.769446] Workqueue: events_unbound deferred_probe_work_func
[    1.775261] PC is at drm_mm_init+0x9c/0xa4
[    1.779339] LR is at lima_vm_create+0x144/0x17c
[ ... ]

Fix the issue by moving the lima_vm_create() call after va_start and
va_end are set up.

The Linux kernel CVE team has assigned CVE-2026-93183 to this issue.


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

	Issue introduced in 5.2 with commit a1d2a6339961efc078208dc3b2f006e9e9a8e119 and fixed in 5.10.270 with commit af1f276d50c9d7ebcd25770f358ca503a89d96d7
	Issue introduced in 5.2 with commit a1d2a6339961efc078208dc3b2f006e9e9a8e119 and fixed in 5.15.221 with commit fd6bc5f1d6b54047b06b82bab25a7e21e4b1c95a
	Issue introduced in 5.2 with commit a1d2a6339961efc078208dc3b2f006e9e9a8e119 and fixed in 6.1.188 with commit ad4e908096dff97646f77b04e2e2825225e215f7
	Issue introduced in 5.2 with commit a1d2a6339961efc078208dc3b2f006e9e9a8e119 and fixed in 6.6.157 with commit 788917ba77f5d69bd368c1d176ecceda346a2951
	Issue introduced in 5.2 with commit a1d2a6339961efc078208dc3b2f006e9e9a8e119 and fixed in 6.12.110 with commit 79a3331ee436c8b1454f897d539606c9b5ebdf9f
	Issue introduced in 5.2 with commit a1d2a6339961efc078208dc3b2f006e9e9a8e119 and fixed in 6.18.52 with commit e2a7cee341986cb5b544a8286edc7fb0494c592e
	Issue introduced in 5.2 with commit a1d2a6339961efc078208dc3b2f006e9e9a8e119 and fixed in 7.2.6 with commit e0773ad25a34a49aece176721c466cf214e02222
	Issue introduced in 5.2 with commit a1d2a6339961efc078208dc3b2f006e9e9a8e119 and fixed in 7.3-rc1 with commit 3b3bce4a692ac60d9f4a341e6b597dd1fd0a28f9

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-2026-93183
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/lima/lima_device.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/af1f276d50c9d7ebcd25770f358ca503a89d96d7
	https://git.kernel.org/stable/c/fd6bc5f1d6b54047b06b82bab25a7e21e4b1c95a
	https://git.kernel.org/stable/c/ad4e908096dff97646f77b04e2e2825225e215f7
	https://git.kernel.org/stable/c/788917ba77f5d69bd368c1d176ecceda346a2951
	https://git.kernel.org/stable/c/79a3331ee436c8b1454f897d539606c9b5ebdf9f
	https://git.kernel.org/stable/c/e2a7cee341986cb5b544a8286edc7fb0494c592e
	https://git.kernel.org/stable/c/e0773ad25a34a49aece176721c466cf214e02222
	https://git.kernel.org/stable/c/3b3bce4a692ac60d9f4a341e6b597dd1fd0a28f9