Upstream information

CVE-2026-89757 at MITRE

Description

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

mm/mglru: fix and remove redundant unevictable folio handling

sort_folio() has a shortcut for moving folios that are no longer evictable
but are still sitting on a generation list. However, this shortcut is
buggy. It does not follow the PG_lru usage convention, and it has a more
serious issue.

Unevictable folios are not threaded on lists[LRU_UNEVICTABLE], so that
folio->lru can be reused to hold folio->mlock_count (see the comment in
lruvec_init()). Hence lruvec_add_folio() skips the list_add() for them,
and every other place that turns a folio unevictable initialises
mlock_count explicitly: lru_add() sets it to 0, __mlock_folio() and
__mlock_new_folio() set it to !!folio_test_mlocked(folio). sort_folio()
sets nothing, and the lru_gen_del_folio() right above it may have already
poisoned folio->lru via list_del(), so mlock_count ends up aliasing
LIST_POISON2, which reads as 0x122, i.e. 290. The result is user
visible. On munlock, __munlock_folio() decrements that bogus count, finds
it still non-zero and bails out before clearing PG_mlocked, so the folio
remains unevictable and the Mlocked accounting stays inflated until the
folio is freed.

The shortcut also touches the LRU flags in the wrong order. It calls
lru_gen_del_folio() while PG_lru is still set, so a concurrent
folio_test_clear_lru() (e.g. compaction, folio_isolate_lru()) can succeed
on a folio that has already been taken off the generation list, which may
lead to unexpected behavior.

So fix it by isolating them as common folios and letting the generic
shrink path cull them. This matches the classical LRU behavior, and there
should be no visible effect on the generic eviction or isolation behavior.

There is no performance concern either, such a folio goes through this
once, and then it is off the generation lists for good.

SUSE information

Overall state of this security issue: New

This issue is currently rated as having moderate severity.

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.

No SUSE Bugzilla entries cross referenced.

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


SUSE Timeline for this CVE

CVE page created: Sat Sep 12 12:54:04 2026
CVE page last modified: Sat Sep 12 12:54:04 2026