CVE-2026-89610: ntfs: verify run length exceeding volume boundary

CVE-2026-89610: ntfs: verify run length exceeding volume boundary

[Greg Kroah-Hartman]

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

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

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

ntfs: verify run length exceeding volume boundary

The mapping pairs decoder validates that the starting LCN is within the
volume but does not check if the run extends beyond the volume boundary.

A malformed NTFS image with a crafted mapping pairs array could cause
the kernel to access memory beyond the volume boundary, potentially leading
to memory corruption and privilege escalation.

Add validation to ensure lcn + length stays within nr_clusters.

The Linux kernel CVE team has assigned CVE-2026-89610 to this issue.


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

	Fixed in 7.2.4 with commit 6e844d4b82434a781b80d02145fd1b17cf90e3c3
	Fixed in 7.3-rc1 with commit fea9e4488f384c0ef1c0e3d96b565127c1b98447

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-2026-89610
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:
	fs/ntfs/runlist.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/6e844d4b82434a781b80d02145fd1b17cf90e3c3
	https://git.kernel.org/stable/c/fea9e4488f384c0ef1c0e3d96b565127c1b98447