{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "07ec77a1d4e82526e1588979fff2f024f8e96df2"
            },
            {
              "fixed": "b22faa21b6230d5eccd233e1b7e0026a5002b287"
            },
            {
              "fixed": "7b5cc7fd1789ea5dbb942c9f8207b076d365badc"
            },
            {
              "fixed": "87ca4f9efbd7cc649ff43b87970888f2812945b8"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/48xxx/CVE-2022-48892.json"
  },
  "details": "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.",
  "id": "CVE-2022-48892",
  "modified": "2026-04-01T23:07:53.901983776Z",
  "published": "2024-08-21T06:10:24.407Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7b5cc7fd1789ea5dbb942c9f8207b076d365badc"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/87ca4f9efbd7cc649ff43b87970888f2812945b8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b22faa21b6230d5eccd233e1b7e0026a5002b287"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/48xxx/CVE-2022-48892.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-48892"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.3",
  "summary": "sched/core: Fix use-after-free bug in dup_user_cpus_ptr()"
}