CVE-2026-72460: apparmor: check label build before no_new_privs test

CVE-2026-72460: apparmor: check label build before no_new_privs test

[Greg Kroah-Hartman]

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

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

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

apparmor: check label build before no_new_privs test

aa_change_profile() builds a replacement label with
fn_label_build_in_scope() before the no_new_privs subset check. The build
helper can fail and return NULL or an ERR_PTR, but the result was passed
to aa_label_is_unconfined_subset() before the existing IS_ERR_OR_NULL()
check.

Reuse the existing target-label build failure handling immediately after
the build. This preserves the current audit handling while preventing the
subset helper from dereferencing an invalid label.

The Linux kernel CVE team has assigned CVE-2026-72460 to this issue.


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

	Issue introduced in 4.13 with commit e00b02bb6ac2a1893227ce8014b649028d6425d2 and fixed in 5.10.261 with commit a29f06db44b4c94597ded58f639eed3e21781ac3
	Issue introduced in 4.13 with commit e00b02bb6ac2a1893227ce8014b649028d6425d2 and fixed in 5.15.212 with commit cfc224866530a6842b6c2d2d30ef6a9b0e64bb9c
	Issue introduced in 4.13 with commit e00b02bb6ac2a1893227ce8014b649028d6425d2 and fixed in 6.1.178 with commit 31cb109db5e6322ed22304fd5c0dedbaa438d6d3
	Issue introduced in 4.13 with commit e00b02bb6ac2a1893227ce8014b649028d6425d2 and fixed in 6.6.145 with commit b7c45c05a396a017c49ac7949de240a0dfc0ac4e
	Issue introduced in 4.13 with commit e00b02bb6ac2a1893227ce8014b649028d6425d2 and fixed in 6.12.97 with commit d84bb195d208adbf77f012ca2a96e11163f6def1
	Issue introduced in 4.13 with commit e00b02bb6ac2a1893227ce8014b649028d6425d2 and fixed in 6.18.40 with commit d82160132345688a09cbaa648cfdd16bb32e8ea2
	Issue introduced in 4.13 with commit e00b02bb6ac2a1893227ce8014b649028d6425d2 and fixed in 7.1.5 with commit ec926b2a351eeeb31e6c9aee02e0c32f94b5588f
	Issue introduced in 4.13 with commit e00b02bb6ac2a1893227ce8014b649028d6425d2 and fixed in 7.2-rc1 with commit a58cafd38b46fb1a2220e2fbbcfe291ea75fa147

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-2026-72460
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:
	security/apparmor/domain.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/a29f06db44b4c94597ded58f639eed3e21781ac3
	https://git.kernel.org/stable/c/cfc224866530a6842b6c2d2d30ef6a9b0e64bb9c
	https://git.kernel.org/stable/c/31cb109db5e6322ed22304fd5c0dedbaa438d6d3
	https://git.kernel.org/stable/c/b7c45c05a396a017c49ac7949de240a0dfc0ac4e
	https://git.kernel.org/stable/c/d84bb195d208adbf77f012ca2a96e11163f6def1
	https://git.kernel.org/stable/c/d82160132345688a09cbaa648cfdd16bb32e8ea2
	https://git.kernel.org/stable/c/ec926b2a351eeeb31e6c9aee02e0c32f94b5588f
	https://git.kernel.org/stable/c/a58cafd38b46fb1a2220e2fbbcfe291ea75fa147