CVE-2026-72206: ntfs: validate index block header more strictly

CVE-2026-72206: ntfs: validate index block header more strictly

[Greg Kroah-Hartman]

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

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

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

ntfs: validate index block header more strictly

Modify ntfs_index_block_inconsisent() to perform stricter validation of
INDEX_HEADER geometry in INDX blocks, and update
ntfs_lookup_inode_by_name() to use that function to validate INDX
blocks.

The Linux kernel CVE team has assigned CVE-2026-72206 to this issue.


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

	Fixed in 7.1.5 with commit 34a49b3e94a50f45b62c6e6f574f676a079ba23e
	Fixed in 7.2-rc1 with commit 14bc34fe948523dc2b0174691f9af9e74eb4f3fd

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-2026-72206
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/dir.c
	fs/ntfs/index.c
	fs/ntfs/index.h


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/34a49b3e94a50f45b62c6e6f574f676a079ba23e
	https://git.kernel.org/stable/c/14bc34fe948523dc2b0174691f9af9e74eb4f3fd