CVE-2022-50100
sched/core: Do not requeue task on CPU excluded from cpus_mask
- Published
- Updated
- Reserved
- Assigned by
- Linux
Description
In the Linux kernel, the following vulnerability has been resolved: sched/core: Do not requeue task on CPU excluded from cpus_mask The following warning was triggered on a large machine early in boot on a distribution kernel but the same problem should also affect mainline. WARNING: CPU: 439 PID: 10 at ../kernel/workqueue.c:2231 process_one_work+0x4d/0x440 Call Trace: <TASK> rescuer_thread+0x1f6/0x360 kthread+0x156/0x180 ret_from_fork+0x22/0x30 </TASK> Commit c6e7bd7afaeb ("sched/core: Optimize ttwu() spinning on p->on_cpu") optimises ttwu by queueing a task that is descheduling on the wakelist, but does not check if the task descheduling is still allowed to run on that CPU. In this warning, the problematic task is a workqueue rescue thread which checks if the rescue is for a per-cpu workqueue and running on the wrong CPU. While this is early in boot and it should be possible to create workers, the rescue thread may still used if the MAYDAY_INITIAL_TIMEOUT is reached or MAYDAY_INTERVAL and on a sufficiently large machine, the rescue thread is being used frequently. Tracing confirmed that the task should have migrated properly using the stopper thread to handle the migration. However, a parallel wakeup from udev running on another CPU that does not share CPU cache observes p->on_cpu and uses task_cpu(p), queues the task on the old CPU and triggers the warning. Check that the wakee task that is descheduling is still allowed to run on its current CPU and if not, wait for the descheduling to complete and select an allowed CPU.
Timeline
ID reserved
By Linux
Published
- 11 months later
· 11 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Analyzed | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.25% · top 83% of all CVEs (7 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.
Affected products
- affected c6e7bd7afaeb3af55ffac122828035f1c01d1d7b – < 748d2e9585ae53cb6be48e84f93d2f082ae1d135
- affected c6e7bd7afaeb3af55ffac122828035f1c01d1d7b – < fde45283f4c8a91c367ea5f20f87036468755121
- affected c6e7bd7afaeb3af55ffac122828035f1c01d1d7b – < 302f7b0fc337746f41c69eb08522907f6a90c643
- affected c6e7bd7afaeb3af55ffac122828035f1c01d1d7b – < 751d4cbc43879229dbc124afefe240b70fd29a85
- affected 5.8
- unaffected < 5.8
- unaffected 5.15.61 – ≤ 5.15.*
- unaffected 5.18.18 – ≤ 5.18.*
- unaffected 5.19.2 – ≤ 5.19.*
- unaffected 6.0 – ≤ *
References (4)
- https://git.kernel.org/stable/c/748d2e9585ae53cb6be48e84f93d2f082ae1d135 (opens in a new tab)
- https://git.kernel.org/stable/c/fde45283f4c8a91c367ea5f20f87036468755121 (opens in a new tab)
- https://git.kernel.org/stable/c/302f7b0fc337746f41c69eb08522907f6a90c643 (opens in a new tab)
- https://git.kernel.org/stable/c/751d4cbc43879229dbc124afefe240b70fd29a85 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2022-50100)Record last updated .