{
  "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-2022-49702",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2022-49702",
    "idYear": 2022,
    "status": "PUBLISHED",
    "publishedAt": "2025-02-26T02:24:22.030Z",
    "updatedAt": "2026-05-11T19:05:05.519Z",
    "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": "btrfs: fix hang during unmount when block group reclaim task is running",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: fix hang during unmount when block group reclaim task is running\n\nWhen we start an unmount, at close_ctree(), if we have the reclaim task\nrunning and in the middle of a data block group relocation, we can trigger\na deadlock when stopping an async reclaim task, producing a trace like the\nfollowing:\n\n[629724.498185] task:kworker/u16:7   state:D stack:    0 pid:681170 ppid:     2 flags:0x00004000\n[629724.499760] Workqueue: events_unbound btrfs_async_reclaim_metadata_space [btrfs]\n[629724.501267] Call Trace:\n[629724.501759]  <TASK>\n[629724.502174]  __schedule+0x3cb/0xed0\n[629724.502842]  schedule+0x4e/0xb0\n[629724.503447]  btrfs_wait_on_delayed_iputs+0x7c/0xc0 [btrfs]\n[629724.504534]  ? prepare_to_wait_exclusive+0xc0/0xc0\n[629724.505442]  flush_space+0x423/0x630 [btrfs]\n[629724.506296]  ? rcu_read_unlock_trace_special+0x20/0x50\n[629724.507259]  ? lock_release+0x220/0x4a0\n[629724.507932]  ? btrfs_get_alloc_profile+0xb3/0x290 [btrfs]\n[629724.508940]  ? do_raw_spin_unlock+0x4b/0xa0\n[629724.509688]  btrfs_async_reclaim_metadata_space+0x139/0x320 [btrfs]\n[629724.510922]  process_one_work+0x252/0x5a0\n[629724.511694]  ? process_one_work+0x5a0/0x5a0\n[629724.512508]  worker_thread+0x52/0x3b0\n[629724.513220]  ? process_one_work+0x5a0/0x5a0\n[629724.514021]  kthread+0xf2/0x120\n[629724.514627]  ? kthread_complete_and_exit+0x20/0x20\n[629724.515526]  ret_from_fork+0x22/0x30\n[629724.516236]  </TASK>\n[629724.516694] task:umount          state:D stack:    0 pid:719055 ppid:695412 flags:0x00004000\n[629724.518269] Call Trace:\n[629724.518746]  <TASK>\n[629724.519160]  __schedule+0x3cb/0xed0\n[629724.519835]  schedule+0x4e/0xb0\n[629724.520467]  schedule_timeout+0xed/0x130\n[629724.521221]  ? lock_release+0x220/0x4a0\n[629724.521946]  ? lock_acquired+0x19c/0x420\n[629724.522662]  ? trace_hardirqs_on+0x1b/0xe0\n[629724.523411]  __wait_for_common+0xaf/0x1f0\n[629724.524189]  ? usleep_range_state+0xb0/0xb0\n[629724.524997]  __flush_work+0x26d/0x530\n[629724.525698]  ? flush_workqueue_prep_pwqs+0x140/0x140\n[629724.526580]  ? lock_acquire+0x1a0/0x310\n[629724.527324]  __cancel_work_timer+0x137/0x1c0\n[629724.528190]  close_ctree+0xfd/0x531 [btrfs]\n[629724.529000]  ? evict_inodes+0x166/0x1c0\n[629724.529510]  generic_shutdown_super+0x74/0x120\n[629724.530103]  kill_anon_super+0x14/0x30\n[629724.530611]  btrfs_kill_super+0x12/0x20 [btrfs]\n[629724.531246]  deactivate_locked_super+0x31/0xa0\n[629724.531817]  cleanup_mnt+0x147/0x1c0\n[629724.532319]  task_work_run+0x5c/0xa0\n[629724.532984]  exit_to_user_mode_prepare+0x1a6/0x1b0\n[629724.533598]  syscall_exit_to_user_mode+0x16/0x40\n[629724.534200]  do_syscall_64+0x48/0x90\n[629724.534667]  entry_SYSCALL_64_after_hwframe+0x44/0xae\n[629724.535318] RIP: 0033:0x7fa2b90437a7\n[629724.535804] RSP: 002b:00007ffe0b7e4458 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6\n[629724.536912] RAX: 0000000000000000 RBX: 00007fa2b9182264 RCX: 00007fa2b90437a7\n[629724.538156] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000555d6cf20dd0\n[629724.539053] RBP: 0000555d6cf20ba0 R08: 0000000000000000 R09: 00007ffe0b7e3200\n[629724.539956] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000\n[629724.540883] R13: 0000555d6cf20dd0 R14: 0000555d6cf20cb0 R15: 0000000000000000\n[629724.541796]  </TASK>\n\nThis happens because:\n\n1) Before entering close_ctree() we have the async block group reclaim\n   task running and relocating a data block group;\n\n2) There's an async metadata (or data) space reclaim task running;\n\n3) We enter close_ctree() and park the cleaner kthread;\n\n4) The async space reclaim task is at flush_space() and runs all the\n   existing delayed iputs;\n\n5) Before the async space reclaim task calls\n   btrfs_wait_on_delayed_iputs(), the block group reclaim task which is\n   doing the data block group relocation, creates a delayed iput at\n   replace_file_extents() (called when COWing leaves that have file extent\n   items pointing to relocated data exten\n---truncated---",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "18bb8bbf13c1839b43c9e09e76d397b753989af2",
              "status": "affected",
              "versionType": "git",
              "lessThan": "341d33128a940c6634175dcb6ca92dc454cfa7d2"
            },
            {
              "version": "18bb8bbf13c1839b43c9e09e76d397b753989af2",
              "status": "affected",
              "versionType": "git",
              "lessThan": "9fadb11f1295289e0da4d3342ecb6b92c1c99540"
            },
            {
              "version": "18bb8bbf13c1839b43c9e09e76d397b753989af2",
              "status": "affected",
              "versionType": "git",
              "lessThan": "31e70e527806c546a72262f2fc3d982ee23c42d3"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "5.13",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "5.13"
            },
            {
              "version": "5.15.51",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "5.18.8",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.18.*"
            },
            {
              "version": "5.19",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}