CVE-2026-97591: s390/crypto: Fix handling of EBUSY in PHMAC when req is pushed to crypto engine

CVE-2026-97591: s390/crypto: Fix handling of EBUSY in PHMAC when req is pushed to crypto engine

[Greg Kroah-Hartman]

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

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

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

s390/crypto: Fix handling of EBUSY in PHMAC when req is pushed to crypto engine

When a request is transferred to the engine via
crypto_transfer_hash_request_to_engine() there are two return codes
signaling a successful transfer: EINPROGRESS and EBUSY. However the
correct handling of EBUSY was missing and has been added as a return
code indicating a successful transfer to the crypto engine.

The Linux kernel CVE team has assigned CVE-2026-97591 to this issue.


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

	Issue introduced in 6.17 with commit cbbc675506cc4cd93e6f895e7c1f693156f9a95c and fixed in 6.18.53 with commit 203702f0013f9b7324e8c5facb6cd6e9c0942b13
	Issue introduced in 6.17 with commit cbbc675506cc4cd93e6f895e7c1f693156f9a95c and fixed in 7.2.7 with commit bcd7f1f1e2f2882ad206f72425255be105178151
	Issue introduced in 6.17 with commit cbbc675506cc4cd93e6f895e7c1f693156f9a95c and fixed in 7.3-rc3 with commit 330148371401de474b656eaf521861f12ec1a1ce

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-2026-97591
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:
	arch/s390/crypto/phmac_s390.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/203702f0013f9b7324e8c5facb6cd6e9c0942b13
	https://git.kernel.org/stable/c/bcd7f1f1e2f2882ad206f72425255be105178151
	https://git.kernel.org/stable/c/330148371401de474b656eaf521861f12ec1a1ce