Subject: CVE-2024-38549: drm/mediatek: Add 0 size check to mtk_drm_gem_obj

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

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

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

drm/mediatek: Add 0 size check to mtk_drm_gem_obj

Add a check to mtk_drm_gem_init if we attempt to allocate a GEM object
of 0 bytes. Currently, no such check exists and the kernel will panic if
a userspace application attempts to allocate a 0x0 GBM buffer.

Tested by attempting to allocate a 0x0 GBM buffer on an MT8188 and
verifying that we now return EINVAL.

The Linux kernel CVE team has assigned CVE-2024-38549 to this issue.

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

	Issue introduced in 4.7 with commit 119f5173628a and fixed in 4.19.316 with commit 790788807954
	Issue introduced in 4.7 with commit 119f5173628a and fixed in 5.4.278 with commit be34a1b351ea
	Issue introduced in 4.7 with commit 119f5173628a and fixed in 5.10.219 with commit d17b75ee9c2e
	Issue introduced in 4.7 with commit 119f5173628a and fixed in 5.15.161 with commit 0e3b6f912372
	Issue introduced in 4.7 with commit 119f5173628a and fixed in 6.1.93 with commit 13562c2d48c9
	Issue introduced in 4.7 with commit 119f5173628a and fixed in 6.6.33 with commit af26ea99019c
	Issue introduced in 4.7 with commit 119f5173628a and fixed in 6.8.12 with commit 9489951e3ae5
	Issue introduced in 4.7 with commit 119f5173628a and fixed in 6.9.3 with commit fb4aabdb1b48
	Issue introduced in 4.7 with commit 119f5173628a and fixed in 6.10 with commit 1e4350095e8a

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-2024-38549
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/mediatek/mtk_drm_gem.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/79078880795478d551a05acc41f957700030d364
	https://git.kernel.org/stable/c/be34a1b351ea7faeb15dde8c44fe89de3980ae67
	https://git.kernel.org/stable/c/d17b75ee9c2e44d3a3682c4ea5ab713ea6073350
	https://git.kernel.org/stable/c/0e3b6f9123726858cac299e1654e3d20424cabe4
	https://git.kernel.org/stable/c/13562c2d48c9ee330de1077d00146742be368f05
	https://git.kernel.org/stable/c/af26ea99019caee1500bf7e60c861136c0bf8594
	https://git.kernel.org/stable/c/9489951e3ae505534c4013db4e76b1b5a3151ac7
	https://git.kernel.org/stable/c/fb4aabdb1b48c25d9e1ee28f89440fd2ce556405
	https://git.kernel.org/stable/c/1e4350095e8ab2577ee05f8c3b044e661b5af9a0