Upstream information

CVE-2026-64108 at MITRE

Description

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

cifs: Fix busy dentry used after unmounting

Since commit 340cea84f691c ("cifs: open files should not hold ref on
superblock"), cifs file only holds the dentry ref_cnt, the cifs file
close work(cfile->deferred) could be executed after unmounting, which
will trigger a warning in generic_shutdown_super:
BUG: Dentry 00000000a14a6845{i=c,n=file} still in use (1) [unmount of
cifs cifs]

The detailed processs is:
process A process B kworker
fd = open(PATH)
vfs_open
file->__f_path = *path // dentry->d_lockref.count = 1
cifs_open
cifs_new_fileinfo
cfile->dentry = dget(dentry) // dentry->d_lockref.count = 2
close(fd)
__fput
cifs_close
queue_delayed_work(deferredclose_wq, cfile->deferred)
dput(dentry) // dentry->d_lockref.count = 1
smb2_deferred_work_close
_cifsFileInfo_put
list_del(&cifs_file->flist)
umount
cleanup_mnt
deactivate_super
cifs_kill_sb
cifs_close_all_deferred_files_sb
cifs_close_all_deferred_files
// cannot find cfile, skip _cifsFileInfo_put
kill_anon_super
generic_shutdown_super
shrink_dcache_for_umount
umount_check
WARN ! // dentry->d_lockref.count = 1
cifsFileInfo_put_final
dput(cifs_file->dentry)
// dentry->d_lockref.count = 0

Fix it by flushing 'deferredclose_wq' before calling kill_anon_super.

Fetch a reproducer in https://bugzilla.kernel.org/show_bug.cgi?id=221548.

SUSE information

Overall state of this security issue: Resolved

This issue is currently rated as having important severity.

CVSS v3 Scores
CVSS detail CNA (NVD) Linux Kernel CNA SUSE
Base Score 7.8 7.8 7
Vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Vector Local Local Local
Attack Complexity Low Low High
Privileges Required Low Low Low
User Interaction None None None
Scope Unchanged Unchanged Unchanged
Confidentiality Impact High High High
Integrity Impact High High High
Availability Impact High High High
CVSSv3 Version 3.1 3.1 3.1
CVSS v4 Scores
CVSS detail SUSE
Base Score 2
Vector CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Attack Vector Local
Attack Complexity Low
Attack Requirements Present
Privileges Required Low
User Interaction None
Vulnerable System Confidentiality Impact None
Vulnerable System Integrity Impact None
Vulnerable System Availability Impact Low
Subsequent System Confidentiality Impact None
Subsequent System Integrity Impact None
Subsequent System Availability Impact None
CVSSv4 Version 4.0

Note from the SUSE Security Team on the kernel-default package

SUSE will no longer fix all CVEs in the Linux Kernel anymore, but declare some bug classes as won't fix. Please refer to TID 21496 for more details.

SUSE Bugzilla entry: 1273747 [RESOLVED / FIXED]

No SUSE Security Announcements cross referenced.


Status of this issue by product and package

Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.

Product(s) Source package State
Products under general support and receiving all security fixes.
SUSE Linux Enterprise Desktop 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Desktop 15 SP7 kernel-source Not affected
SUSE Linux Enterprise High Availability Extension 15 SP7 kernel-default Not affected
SUSE Linux Enterprise High Availability Extension 15 SP7 kernel-source Not affected
SUSE Linux Enterprise High Availability Extension 16.0 kernel-default Not affected
SUSE Linux Enterprise High Availability Extension 16.0 kernel-source Not affected
SUSE Linux Enterprise High Availability Extension 16.1 kernel-default Not affected
SUSE Linux Enterprise High Availability Extension 16.1 kernel-source Not affected
SUSE Linux Enterprise Live Patching 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Live Patching 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Micro 5.3 kernel-default Not affected
SUSE Linux Enterprise Micro 5.3 kernel-rt Not affected
SUSE Linux Enterprise Micro 5.3 kernel-source Not affected
SUSE Linux Enterprise Micro 5.3 kernel-source-rt Not affected
SUSE Linux Enterprise Micro 5.4 kernel-default Not affected
SUSE Linux Enterprise Micro 5.4 kernel-rt Not affected
SUSE Linux Enterprise Micro 5.4 kernel-source Not affected
SUSE Linux Enterprise Micro 5.4 kernel-source-rt Not affected
SUSE Linux Enterprise Micro 5.5 kernel-default Not affected
SUSE Linux Enterprise Micro 5.5 kernel-source Not affected
SUSE Linux Enterprise Micro 5.5 kernel-source-rt Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Module for Legacy 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Module for Legacy 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Module for Public Cloud 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Module for Public Cloud 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP7 kernel-source-rt Not affected
SUSE Linux Enterprise Server 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Server 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Server 16.0 kernel-default Not affected
SUSE Linux Enterprise Server 16.0 kernel-source Not affected
SUSE Linux Enterprise Server 16.1 kernel-default Not affected
SUSE Linux Enterprise Server 16.1 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP7 kernel-source Not affected
SUSE Linux Enterprise Server for SAP applications 16.0 kernel-default Not affected
SUSE Linux Enterprise Server for SAP applications 16.0 kernel-source Not affected
SUSE Linux Enterprise Server for SAP applications 16.1 kernel-default Not affected
SUSE Linux Enterprise Server for SAP applications 16.1 kernel-source Not affected
SUSE Linux Enterprise Workstation Extension 15 SP7 kernel-default Not affected
SUSE Linux Enterprise Workstation Extension 15 SP7 kernel-source Not affected
SUSE Linux Micro 6.0 kernel-default Not affected
SUSE Linux Micro 6.0 kernel-source Not affected
SUSE Linux Micro 6.0 kernel-source-rt Not affected
SUSE Linux Micro 6.1 kernel-default Not affected
SUSE Linux Micro 6.1 kernel-source Not affected
SUSE Linux Micro 6.1 kernel-source-rt Not affected
SUSE Linux Micro 6.2 kernel-default Not affected
SUSE Linux Micro 6.2 kernel-source Not affected
SUSE Linux Micro Extras 6.0 kernel-default Not affected
SUSE Linux Micro Extras 6.0 kernel-source Not affected
SUSE Linux Micro Extras 6.0 kernel-source-rt Not affected
SUSE Real Time Module 15 SP7 kernel-source-rt Not affected
openSUSE Leap 16.0 kernel-source Not affected
Products under Long Term Service Pack support and receiving important and critical security fixes.
SUSE Linux Enterprise High Performance Computing 12 SP5 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS kernel-default Not affected
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS kernel-default Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS kernel-source Not affected
SUSE Linux Enterprise Live Patching 12 SP5 kernel-default Not affected
SUSE Linux Enterprise Live Patching 12 SP5 kernel-source Not affected
SUSE Linux Enterprise Live Patching 15 SP4 kernel-default Not affected
SUSE Linux Enterprise Live Patching 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Live Patching 15 SP5 kernel-default Not affected
SUSE Linux Enterprise Live Patching 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE kernel-default Not affected
SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE kernel-source Not affected
SUSE Linux Enterprise Server 12 SP5 kernel-source Not affected
SUSE Linux Enterprise Server 12 SP5-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 12 SP5-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP4-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP4-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP5-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP5-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP6 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP6-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP6-LTSS kernel-source Not affected
SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 kernel-default Not affected
SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP4 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP5 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP6 kernel-default Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP6 kernel-source Not affected
SUSE Manager Proxy 4.3 kernel-source Not affected
SUSE Manager Proxy LTS 4.3 kernel-source Not affected
SUSE Manager Retail Branch Server 4.3 kernel-source Not affected
SUSE Manager Retail Branch Server LTS 4.3 kernel-source Not affected
SUSE Manager Server 4.3 kernel-source Not affected
SUSE Manager Server LTS 4.3 kernel-source Not affected
Products past their end of life and not receiving proactive updates anymore.
SUSE CaaS Platform 4.0 kernel-source Not affected
SUSE Enterprise Storage 6 kernel-source Not affected
SUSE Enterprise Storage 7 kernel-source Not affected
SUSE Enterprise Storage 7.1 kernel-source Not affected
SUSE Linux Enterprise Desktop 11 SP4 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP3 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP5 kernel-source Not affected
SUSE Linux Enterprise Desktop 15 SP6 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP1 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP2 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP3 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP4 kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS kernel-source Not affected
SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS kernel-source Not affected
SUSE Linux Enterprise Micro 5.0 kernel-default Not affected
SUSE Linux Enterprise Micro 5.1 kernel-default Not affected
SUSE Linux Enterprise Micro 5.2 kernel-default Not affected
SUSE Linux Enterprise Micro 5.2 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Module for Basesystem 15 SP3 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Module for Development Tools 15 SP3 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP3 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP4 kernel-source Not affected
SUSE Linux Enterprise Real Time 15 SP4 kernel-source-rt Not affected
SUSE Linux Enterprise Real Time 15 SP5 kernel-source-rt Not affected
SUSE Linux Enterprise Server 11 SP4 kernel-source Not affected
SUSE Linux Enterprise Server 11 SP4-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP1-BCL kernel-source Not affected
SUSE Linux Enterprise Server 15 SP1-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP1-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP2-BCL kernel-source Not affected
SUSE Linux Enterprise Server 15 SP2-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP2-LTSS kernel-source Not affected
SUSE Linux Enterprise Server 15 SP3 kernel-source Not affected
SUSE Linux Enterprise Server 15 SP3-BCL kernel-source Not affected
SUSE Linux Enterprise Server 15 SP3-LTSS kernel-default Not affected
SUSE Linux Enterprise Server 15 SP3-LTSS kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP1 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP2 kernel-source Not affected
SUSE Linux Enterprise Server for SAP Applications 15 SP3 kernel-source Not affected
SUSE Manager Proxy 4.0 kernel-source Not affected
SUSE Manager Proxy 4.1 kernel-source Not affected
SUSE Manager Proxy 4.2 kernel-source Not affected
SUSE Manager Retail Branch Server 4.0 kernel-source Not affected
SUSE Manager Retail Branch Server 4.1 kernel-source Not affected
SUSE Manager Retail Branch Server 4.2 kernel-source Not affected
SUSE Manager Server 4.0 kernel-source Not affected
SUSE Manager Server 4.1 kernel-source Not affected
SUSE Manager Server 4.2 kernel-source Not affected
SUSE Real Time Module 15 SP4 kernel-source-rt Not affected
SUSE Real Time Module 15 SP5 kernel-source-rt Not affected
openSUSE Leap 15.3 kernel-source Not affected
openSUSE Leap 15.4 kernel-source Not affected
openSUSE Leap 15.4 kernel-source-rt Not affected
openSUSE Leap 15.5 kernel-source Not affected
openSUSE Leap 15.5 kernel-source-rt Not affected
openSUSE Leap 15.6 kernel-source Not affected


SUSE Timeline for this CVE

CVE page created: Mon Jul 20 11:54:24 2026
CVE page last modified: Fri Aug 28 20:08:26 2026