CVE-2026-74291: ASoC: topology: Check PCM and DAI name strings before use

CVE-2026-74291: ASoC: topology: Check PCM and DAI name strings before use

[Greg Kroah-Hartman]

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

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

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

ASoC: topology: Check PCM and DAI name strings before use

Topology objects store several PCM and DAI names in fixed-size UAPI
arrays. Other topology parser paths validate these fields with bounded
strnlen() checks before using them as C strings, but the PCM and DAI
paths still pass some fixed-size arrays directly to strlen(),
devm_kstrdup(), DAI lookup, and diagnostic prints.

A malformed topology blob with a non-NUL-terminated PCM, DAI, or stream
capability name can therefore make the parser read past the end of the
fixed-size field.

Reject unterminated PCM and DAI name fields before consuming them as C
strings.

The Linux kernel CVE team has assigned CVE-2026-74291 to this issue.


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

	Issue introduced in 4.6 with commit 64527e8a352968bda529f01df1c9dd5fe581ff04 and fixed in 7.1.5 with commit ba37b62ed0a443b8e23f53a7477e7f2537fd34c7
	Issue introduced in 4.6 with commit 64527e8a352968bda529f01df1c9dd5fe581ff04 and fixed in 7.2-rc1 with commit b7e44d1986d6671342c19b82192189ca5db5dab7

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-2026-74291
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:
	sound/soc/soc-topology.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/ba37b62ed0a443b8e23f53a7477e7f2537fd34c7
	https://git.kernel.org/stable/c/b7e44d1986d6671342c19b82192189ca5db5dab7