{"cve":"CVE-2024-42245","nvd":{"published":"2024-08-07T16:15:47.230","modified":"2026-06-17T07:49:05.737","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nRevert \"sched/fair: Make sure to try to detach at least one movable task\"\n\nThis reverts commit b0defa7ae03ecf91b8bfd10ede430cff12fcbd06.\n\nb0defa7ae03ec changed the load balancing logic to ignore env.max_loop if\nall tasks examined to that point were pinned. The goal of the patch was\nto make it more likely to be able to detach a task buried in a long list\nof pinned tasks. However, this has the unfortunate side effect of\ncreating an O(n) iteration in detach_tasks(), as we now must fully\niterate every task on a cpu if all or most are pinned. Since this load\nbalance code is done with rq lock held, and often in softirq context, it\nis very easy to trigger hard lockups. We observed such hard lockups with\na user who affined O(10k) threads to a single cpu.\n\nWhen I discussed this with Vincent he initially suggested that we keep\nthe limit on the number of tasks to detach, but increase the number of\ntasks we can search. However, after some back and forth on the mailing\nlist, he recommended we instead revert the original patch, as it seems\nlikely no one was actually getting hit by the original issue.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-667"],"references":["https://git.kernel.org/stable/c/0fa6dcbfa2e2b97c1e6febbea561badf0931a38b","https://git.kernel.org/stable/c/1e116c18e32b035a2d1bd460800072c8bf96bc44","https://git.kernel.org/stable/c/2feab2492deb2f14f9675dd6388e9e2bf669c27a","https://git.kernel.org/stable/c/d467194018dd536fe6c65a2fd3aedfcdb1424903","https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:53:51.317825789+00:00"},"epss":{"cve":"CVE-2024-42245","score":0.00166,"percentile":0.05793,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}