{"cve":"CVE-2022-48892","nvd":{"published":"2024-08-21T07:15:05.420","modified":"2026-08-04T10:17:25.630","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched/core: Fix use-after-free bug in dup_user_cpus_ptr()\n\nSince commit 07ec77a1d4e8 (\"sched: Allow task CPU affinity to be\nrestricted on asymmetric systems\"), the setting and clearing of\nuser_cpus_ptr are done under pi_lock for arm64 architecture. However,\ndup_user_cpus_ptr() accesses user_cpus_ptr without any lock\nprotection. Since sched_setaffinity() can be invoked from another\nprocess, the process being modified may be undergoing fork() at\nthe same time.  When racing with the clearing of user_cpus_ptr in\n__set_cpus_allowed_ptr_locked(), it can lead to user-after-free and\npossibly double-free in arm64 kernel.\n\nCommit 8f9ea86fdf99 (\"sched: Always preserve the user requested\ncpumask\") fixes this problem as user_cpus_ptr, once set, will never\nbe cleared in a task's lifetime. However, this bug was re-introduced\nin commit 851a723e45d1 (\"sched: Always clear user_cpus_ptr in\ndo_set_cpus_allowed()\") which allows the clearing of user_cpus_ptr in\ndo_set_cpus_allowed(). This time, it will affect all arches.\n\nFix this bug by always clearing the user_cpus_ptr of the newly\ncloned/forked task before the copying process starts and check the\nuser_cpus_ptr state of the source task under pi_lock.\n\nNote to stable, this patch won't be applicable to stable releases.\nJust copy the new dup_user_cpus_ptr() function over.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-415","CWE-416"],"references":["https://git.kernel.org/stable/c/7b5cc7fd1789ea5dbb942c9f8207b076d365badc","https://git.kernel.org/stable/c/87ca4f9efbd7cc649ff43b87970888f2812945b8","https://git.kernel.org/stable/c/b22faa21b6230d5eccd233e1b7e0026a5002b287"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:54:16.205165117+00:00"},"epss":{"cve":"CVE-2022-48892","score":0.00249,"percentile":0.16284,"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."]}