CVE-2026-98418 (GCVE-0-2026-98418)
Vulnerability from cvelistv5
Published
2026-10-14 13:27
Modified
2026-10-19 09:19
Severity ?
VLAI Severity ?
EPSS score ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
sched/core: Avoid false migration warning for proxy donors
Proxy execution can move a blocked donor's scheduling context to the
lock owner's CPU even when the donor is migration-disabled. The donor
does not execute there, and its original execution CPU remains recorded
in wake_cpu.
set_task_cpu() warns unconditionally for migration-disabled tasks, so a
subsequent proxy migration or the wakeup path returning the donor home
triggers a false positive: moving a blocked scheduling context does not
violate the migration-disabled execution context.
For example, creating a mutex owner on CPU1 and a migration-disabled
waiter on CPU0 can trigger the following warning:
proxy_migrate_repro: donor blocking on CPU0 with migration disabled
proxy_migrate_repro: donor moved from CPU0 to CPU1
WARNING: kernel/sched/core.c:3389 at set_task_cpu+0x1d3/0x280
...
Call Trace:
try_to_wake_up+0x43f/0x780
__mutex_unlock_slowpath+0x330/0x540
owner_fn+0x9f/0xc0 [proxy_migrate_repro]
...
proxy_migrate_repro: donor woke on CPU0, task_cpu=0
proxy_migrate_repro: completed
Exclude blocked proxy donors from the warning. The proxy wakeup path
restores an executable placement before clearing the blocked state.
References
Impacted products
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"kernel/sched/core.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "e4a442da49fff7619b3cb2988e477022dcea6688",
"status": "affected",
"version": "b049b81bdff6fc6794200a4c7d7d910e2008d57f",
"versionType": "git"
},
{
"lessThan": "fe3c73d7bc769e7afc252f867a3421fe168b898d",
"status": "affected",
"version": "b049b81bdff6fc6794200a4c7d7d910e2008d57f",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"kernel/sched/core.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "7.1"
},
{
"lessThan": "7.1",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.2.*",
"status": "unaffected",
"version": "7.2.8",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.2.8",
"versionStartIncluding": "7.1",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.3",
"versionStartIncluding": "7.1",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched/core: Avoid false migration warning for proxy donors\n\nProxy execution can move a blocked donor\u0027s scheduling context to the\nlock owner\u0027s CPU even when the donor is migration-disabled. The donor\ndoes not execute there, and its original execution CPU remains recorded\nin wake_cpu.\n\nset_task_cpu() warns unconditionally for migration-disabled tasks, so a\nsubsequent proxy migration or the wakeup path returning the donor home\ntriggers a false positive: moving a blocked scheduling context does not\nviolate the migration-disabled execution context.\n\nFor example, creating a mutex owner on CPU1 and a migration-disabled\nwaiter on CPU0 can trigger the following warning:\n\n proxy_migrate_repro: donor blocking on CPU0 with migration disabled\n proxy_migrate_repro: donor moved from CPU0 to CPU1\n WARNING: kernel/sched/core.c:3389 at set_task_cpu+0x1d3/0x280\n ...\n Call Trace:\n try_to_wake_up+0x43f/0x780\n __mutex_unlock_slowpath+0x330/0x540\n owner_fn+0x9f/0xc0 [proxy_migrate_repro]\n ...\n proxy_migrate_repro: donor woke on CPU0, task_cpu=0\n proxy_migrate_repro: completed\n\nExclude blocked proxy donors from the warning. The proxy wakeup path\nrestores an executable placement before clearing the blocked state."
}
],
"providerMetadata": {
"dateUpdated": "2026-10-19T09:19:11.970Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/e4a442da49fff7619b3cb2988e477022dcea6688"
},
{
"url": "https://git.kernel.org/stable/c/fe3c73d7bc769e7afc252f867a3421fe168b898d"
}
],
"title": "sched/core: Avoid false migration warning for proxy donors",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-98418",
"datePublished": "2026-10-14T13:27:48.406Z",
"dateReserved": "2026-09-25T10:25:14.347Z",
"dateUpdated": "2026-10-19T09:19:11.970Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
Loading…
Loading…
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
Loading…
Loading…