CVE-2026-64153: drm/msm: Fix iommu_map_sgtable() return value check and avoid WARN

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

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

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

drm/msm: Fix iommu_map_sgtable() return value check and avoid WARN

Commit "iommu: return full error code from iommu_map_sg[_atomic]()"
changed iommu_map_sgtable() to return an ssize_t and negative values
in error cases, rather than a size_t and a zero.

Store the return value in the appropriate type and in case of error,
return it rather than WARNing.

Patchwork: https://patchwork.freedesktop.org/patch/719685/

The Linux kernel CVE team has assigned CVE-2026-64153 to this issue.


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

	Issue introduced in 5.15 with commit ad8f36e4b6b1c826a0daa5fda2c5839205b5aa8b and fixed in 5.15.209 with commit 3c2cdb7c07f664b77e2a75b50793b845d5742efa
	Issue introduced in 5.15 with commit ad8f36e4b6b1c826a0daa5fda2c5839205b5aa8b and fixed in 6.1.175 with commit 3e3c3c95ef4fe17231a9149e27bcfc9dae2dd89f
	Issue introduced in 5.15 with commit ad8f36e4b6b1c826a0daa5fda2c5839205b5aa8b and fixed in 6.6.142 with commit 7256e54583aee21e23929e7554278c2f5c1a08b1
	Issue introduced in 5.15 with commit ad8f36e4b6b1c826a0daa5fda2c5839205b5aa8b and fixed in 6.12.92 with commit 3457807aeb88077712f0a7cb65c3ca5120773d75
	Issue introduced in 5.15 with commit ad8f36e4b6b1c826a0daa5fda2c5839205b5aa8b and fixed in 6.18.34 with commit f4e37f3df436c2bdd2621c21f9c72c8f149a221d
	Issue introduced in 5.15 with commit ad8f36e4b6b1c826a0daa5fda2c5839205b5aa8b and fixed in 7.0.11 with commit 3a45af37733446e114bf19b0209fe7d8089bdb8b
	Issue introduced in 5.15 with commit ad8f36e4b6b1c826a0daa5fda2c5839205b5aa8b and fixed in 7.1 with commit 55e0f0d1c1a4ee1e46da7da4d443eb3044fb3851

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-2026-64153
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/msm/msm_iommu.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/3c2cdb7c07f664b77e2a75b50793b845d5742efa
	https://git.kernel.org/stable/c/3e3c3c95ef4fe17231a9149e27bcfc9dae2dd89f
	https://git.kernel.org/stable/c/7256e54583aee21e23929e7554278c2f5c1a08b1
	https://git.kernel.org/stable/c/3457807aeb88077712f0a7cb65c3ca5120773d75
	https://git.kernel.org/stable/c/f4e37f3df436c2bdd2621c21f9c72c8f149a221d
	https://git.kernel.org/stable/c/3a45af37733446e114bf19b0209fe7d8089bdb8b
	https://git.kernel.org/stable/c/55e0f0d1c1a4ee1e46da7da4d443eb3044fb3851