s390/vfio-ap: Fix NULL deref in status_show() during queue probe

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-89955
StatePUBLISHED
AssignerLinux
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-09-16 11:17:05 UTC
Updated2026-10-19 09:18:41 UTC
DescriptionIn the Linux kernel, the following vulnerability has been resolved: s390/vfio-ap: Fix NULL deref in status_show() during queue probe When vfio_ap_mdev_probe_queue() creates the sysfs attribute group, the queue's driver data has not yet been set. A concurrent read of the 'status' attribute can therefore call dev_get_drvdata() and get NULL, which is then passed directly to vfio_ap_mdev_for_queue() where q->apqn is unconditionally dereferenced, causing a NULL pointer dereference. Fix this by acquiring the update locks before calling sysfs_create_group(). The status_show() function acquires guests_lock before reading the driver data, so any concurrent read will block until after dev_set_drvdata() has been called and the update locks are released. As a bonus, the APQN no longer needs to be read from the queue struct after allocation — it can be read directly from apdev before allocation and stored in a local variable, which is then assigned to q->apqn once the allocation succeeds.

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Linux Linux affected 260f3ea141382386e97611e7c2029bc013088ab1 31fa0a8a3c337ed2d200166d6926ab23c14f8b2e git Not specified
CNA Linux Linux affected 260f3ea141382386e97611e7c2029bc013088ab1 e102ce0f4af99dff769a4b1b4daa4cc6bd5ad2d9 git Not specified
CNA Linux Linux affected 260f3ea141382386e97611e7c2029bc013088ab1 69632952aca04caa71e49953b6949fc04e788e67 git Not specified
CNA Linux Linux affected 260f3ea141382386e97611e7c2029bc013088ab1 7db2511fc601ca3a6e3fb1bdce02261c3c3167c3 git Not specified
CNA Linux Linux affected 260f3ea141382386e97611e7c2029bc013088ab1 dd6f4ef6f8a37412909ad787c837332fb070159c git Not specified
CNA Linux Linux affected 6.0 Not specified
CNA Linux Linux unaffected 6.0 semver Not specified
CNA Linux Linux unaffected 6.6.157 6.6.* semver Not specified
CNA Linux Linux unaffected 6.12.110 6.12.* semver Not specified
CNA Linux Linux unaffected 6.18.51 6.18.* semver Not specified
CNA Linux Linux unaffected 7.2.5 7.2.* semver Not specified
CNA Linux Linux unaffected 7.3 * original_commit_for_fix Not specified

References

ReferenceSourceLinkTags
git.kernel.org/stable/c/69632952aca04caa71e49953b6949fc04e788e67 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/7db2511fc601ca3a6e3fb1bdce02261c3c3167c3 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/31fa0a8a3c337ed2d200166d6926ab23c14f8b2e 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/e102ce0f4af99dff769a4b1b4daa4cc6bd5ad2d9 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/dd6f4ef6f8a37412909ad787c837332fb070159c 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report