CVE-2026-72305: VDUSE: avoid leaking information to userspace

CVE-2026-72305: VDUSE: avoid leaking information to userspace

[Greg Kroah-Hartman]

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

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

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

VDUSE: avoid leaking information to userspace

The bounceing is not necessarily page aligned, so current VDUSE can
leak kernel information through mapping bounce pages to
userspace. Allocate bounce pages with __GFP_ZERO to avoid leaking
information to userspace.

The Linux kernel CVE team has assigned CVE-2026-72305 to this issue.


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

	Issue introduced in 5.15 with commit 8c773d53fb7b64267b0f55c1d3517cb8c5e29b3c and fixed in 6.6.148 with commit fde25641cbddd0c084e3320d08f755e7e6acfae5
	Issue introduced in 5.15 with commit 8c773d53fb7b64267b0f55c1d3517cb8c5e29b3c and fixed in 6.12.101 with commit 5e88c1bc3a41d9a260dd42bae8ad18fd4f35bbe1
	Issue introduced in 5.15 with commit 8c773d53fb7b64267b0f55c1d3517cb8c5e29b3c and fixed in 6.18.42 with commit 690fb82c4122f8c2656fa4f842275132771b68b9
	Issue introduced in 5.15 with commit 8c773d53fb7b64267b0f55c1d3517cb8c5e29b3c and fixed in 7.1.5 with commit 00335df9da2011e095f846d645cc2e9fd2907659
	Issue introduced in 5.15 with commit 8c773d53fb7b64267b0f55c1d3517cb8c5e29b3c and fixed in 7.2-rc1 with commit 9c1523803445ee0348f62b77793266dd981596e0

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-2026-72305
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/vdpa/vdpa_user/iova_domain.c
	drivers/vdpa/vdpa_user/vduse_dev.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/fde25641cbddd0c084e3320d08f755e7e6acfae5
	https://git.kernel.org/stable/c/5e88c1bc3a41d9a260dd42bae8ad18fd4f35bbe1
	https://git.kernel.org/stable/c/690fb82c4122f8c2656fa4f842275132771b68b9
	https://git.kernel.org/stable/c/00335df9da2011e095f846d645cc2e9fd2907659
	https://git.kernel.org/stable/c/9c1523803445ee0348f62b77793266dd981596e0