sched/core: Make core-sched flips wait for in-flight selections
In the Linux kernel, the following vulnerability has been resolved: sched/core: Make core-sched flips wait for in-flight selections Core scheduling's pick_next_task() operates on all sibling rqs under one acquisition of the shared core-wide lock. A ->pick_task() that releases the rq lock leaves every sibling __lock momentarily free, letting __sched_core_flip(false) complete mid-selection and rebind rq_lockp() under it. The selection resumes on the split locks, touching sibling state it no longer protects, and __schedule() finally releases a lock that was never taken while leaking the one that was. Count in-flight core-wide selections in the leader's rq->core_pick_in_flight and make __sched_core_flip() wait for the count to drain. The count only changes under the shared lock, which the flip holds while sampling, so no other ordering is needed. The wait can repeat while selections overlap, but the flip backs off between samples and flips are rare cookie-lifetime events. sched_core_cpu_deactivate() moves the count to the new leader - a stale copy left behind would bias it forever if that CPU later returns as its own leader.
CVE-2026-89520
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-89520
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "539f65125d20aacab54d02d77f10a839f45b09dc",
"lessThan": "a2a16896ed53046f275f56a6cd8ca3fb6f12c4f3",
"versionType": "git"
},
{
"status": "affected",
"version": "539f65125d20aacab54d02d77f10a839f45b09dc",
"lessThan": "3e2511bffa93a639774a99e392181e21d28677e2",
"versionType": "git"
},
{
"status": "affected",
"version": "539f65125d20aacab54d02d77f10a839f45b09dc",
"lessThan": "9d69422ddaa13526c2223444e237d948d6e44728",
"versionType": "git"
},
{
"status": "affected",
"version": "539f65125d20aacab54d02d77f10a839f45b09dc",
"lessThan": "23eda24f325a6e6d686d30ec75f2e9d6745e2015",
"versionType": "git"
},
{
"status": "affected",
"version": "539f65125d20aacab54d02d77f10a839f45b09dc",
"lessThan": "f3629c63a4af3e491381780bc6c123cb498c4c40",
"versionType": "git"
}
],
"programFiles": [
"kernel/sched/core.c",
"kernel/sched/sched.h"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.14"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.14",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.160",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.112",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.51",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.4",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"kernel/sched/core.c",
"kernel/sched/sched.h"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-89520
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #46667 · Revision 1
- Added to Heist Feed
- Publisher date