{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2022-49783",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2022-49783",
    "idYear": 2022,
    "status": "PUBLISHED",
    "publishedAt": "2025-05-01T14:09:17.054Z",
    "updatedAt": "2026-05-11T19:06:41.833Z",
    "importedAt": "2026-10-24T01:56:49.724Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "x86/fpu: Drop fpregs lock before inheriting FPU permissions",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/fpu: Drop fpregs lock before inheriting FPU permissions\n\nMike Galbraith reported the following against an old fork of preempt-rt\nbut the same issue also applies to the current preempt-rt tree.\n\n   BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46\n   in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: systemd\n   preempt_count: 1, expected: 0\n   RCU nest depth: 0, expected: 0\n   Preemption disabled at:\n   fpu_clone\n   CPU: 6 PID: 1 Comm: systemd Tainted: G            E       (unreleased)\n   Call Trace:\n    <TASK>\n    dump_stack_lvl\n    ? fpu_clone\n    __might_resched\n    rt_spin_lock\n    fpu_clone\n    ? copy_thread\n    ? copy_process\n    ? shmem_alloc_inode\n    ? kmem_cache_alloc\n    ? kernel_clone\n    ? __do_sys_clone\n    ? do_syscall_64\n    ? __x64_sys_rt_sigprocmask\n    ? syscall_exit_to_user_mode\n    ? do_syscall_64\n    ? syscall_exit_to_user_mode\n    ? do_syscall_64\n    ? syscall_exit_to_user_mode\n    ? do_syscall_64\n    ? exc_page_fault\n    ? entry_SYSCALL_64_after_hwframe\n    </TASK>\n\nMike says:\n\n  The splat comes from fpu_inherit_perms() being called under fpregs_lock(),\n  and us reaching the spin_lock_irq() therein due to fpu_state_size_dynamic()\n  returning true despite static key __fpu_state_size_dynamic having never\n  been enabled.\n\nMike's assessment looks correct. fpregs_lock on a PREEMPT_RT kernel disables\npreemption so calling spin_lock_irq() in fpu_inherit_perms() is unsafe. This\nproblem exists since commit\n\n  9e798e9aa14c (\"x86/fpu: Prepare fpu_clone() for dynamically enabled features\").\n\nEven though the original bug report should not have enabled the paths at\nall, the bug still exists.\n\nfpregs_lock is necessary when editing the FPU registers or a task's FP\nstate but it is not necessary for fpu_inherit_perms(). The only write\nof any FP state in fpu_inherit_perms() is for the new child which is\nnot running yet and cannot context switch or be borrowed by a kernel\nthread yet. Hence, fpregs_lock is not protecting anything in the new\nchild until clone() completes and can be dropped earlier. The siglock\nstill needs to be acquired by fpu_inherit_perms() as the read of the\nparent's permissions has to be serialised.\n\n  [ bp: Cleanup splat. ]",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "9e798e9aa14c45fb94e47b30bf6347b369ce9df7",
              "status": "affected",
              "versionType": "git",
              "lessThan": "c6e8a7a1780af3da65e78a615f7d0874da6aabb0"
            },
            {
              "version": "9e798e9aa14c45fb94e47b30bf6347b369ce9df7",
              "status": "affected",
              "versionType": "git",
              "lessThan": "36b038791e1e2baea892e9276588815fd14894b4"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "5.16",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "5.16"
            },
            {
              "version": "6.0.10",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.0.*"
            },
            {
              "version": "6.1",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}