Vulnerability-Lookup

GHSA-6HQ8-G74X-24Q3

Vulnerability from github – Published: 2025-10-24 18:30 – Updated: 2025-10-24 18:30

Details

In the Linux kernel, the following vulnerability has been resolved:

btrfs: fix hang during unmount when block group reclaim task is running

When we start an unmount, at close_ctree(), if we have the reclaim task running and in the middle of a data block group relocation, we can trigger a deadlock when stopping an async reclaim task, producing a trace like the following:

[629724.498185] task:kworker/u16:7 state:D stack: 0 pid:681170 ppid: 2 flags:0x00004000 [629724.499760] Workqueue: events_unbound btrfs_async_reclaim_metadata_space [btrfs] [629724.501267] Call Trace: [629724.501759] [629724.502174] __schedule+0x3cb/0xed0 [629724.502842] schedule+0x4e/0xb0 [629724.503447] btrfs_wait_on_delayed_iputs+0x7c/0xc0 [btrfs] [629724.504534] ? prepare_to_wait_exclusive+0xc0/0xc0 [629724.505442] flush_space+0x423/0x630 [btrfs] [629724.506296] ? rcu_read_unlock_trace_special+0x20/0x50 [629724.507259] ? lock_release+0x220/0x4a0 [629724.507932] ? btrfs_get_alloc_profile+0xb3/0x290 [btrfs] [629724.508940] ? do_raw_spin_unlock+0x4b/0xa0 [629724.509688] btrfs_async_reclaim_metadata_space+0x139/0x320 [btrfs] [629724.510922] process_one_work+0x252/0x5a0 [629724.511694] ? process_one_work+0x5a0/0x5a0 [629724.512508] worker_thread+0x52/0x3b0 [629724.513220] ? process_one_work+0x5a0/0x5a0 [629724.514021] kthread+0xf2/0x120 [629724.514627] ? kthread_complete_and_exit+0x20/0x20 [629724.515526] ret_from_fork+0x22/0x30 [629724.516236] [629724.516694] task:umount state:D stack: 0 pid:719055 ppid:695412 flags:0x00004000 [629724.518269] Call Trace: [629724.518746] [629724.519160] __schedule+0x3cb/0xed0 [629724.519835] schedule+0x4e/0xb0 [629724.520467] schedule_timeout+0xed/0x130 [629724.521221] ? lock_release+0x220/0x4a0 [629724.521946] ? lock_acquired+0x19c/0x420 [629724.522662] ? trace_hardirqs_on+0x1b/0xe0 [629724.523411] __wait_for_common+0xaf/0x1f0 [629724.524189] ? usleep_range_state+0xb0/0xb0 [629724.524997] __flush_work+0x26d/0x530 [629724.525698] ? flush_workqueue_prep_pwqs+0x140/0x140 [629724.526580] ? lock_acquire+0x1a0/0x310 [629724.527324] __cancel_work_timer+0x137/0x1c0 [629724.528190] close_ctree+0xfd/0x531 [btrfs] [629724.529000] ? evict_inodes+0x166/0x1c0 [629724.529510] generic_shutdown_super+0x74/0x120 [629724.530103] kill_anon_super+0x14/0x30 [629724.530611] btrfs_kill_super+0x12/0x20 [btrfs] [629724.531246] deactivate_locked_super+0x31/0xa0 [629724.531817] cleanup_mnt+0x147/0x1c0 [629724.532319] task_work_run+0x5c/0xa0 [629724.532984] exit_to_user_mode_prepare+0x1a6/0x1b0 [629724.533598] syscall_exit_to_user_mode+0x16/0x40 [629724.534200] do_syscall_64+0x48/0x90 [629724.534667] entry_SYSCALL_64_after_hwframe+0x44/0xae [629724.535318] RIP: 0033:0x7fa2b90437a7 [629724.535804] RSP: 002b:00007ffe0b7e4458 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 [629724.536912] RAX: 0000000000000000 RBX: 00007fa2b9182264 RCX: 00007fa2b90437a7 [629724.538156] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000555d6cf20dd0 [629724.539053] RBP: 0000555d6cf20ba0 R08: 0000000000000000 R09: 00007ffe0b7e3200 [629724.539956] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [629724.540883] R13: 0000555d6cf20dd0 R14: 0000555d6cf20cb0 R15: 0000000000000000 [629724.541796]

This happens because:

1) Before entering close_ctree() we have the async block group reclaim task running and relocating a data block group;

2) There's an async metadata (or data) space reclaim task running;

3) We enter close_ctree() and park the cleaner kthread;

4) The async space reclaim task is at flush_space() and runs all the existing delayed iputs;

5) Before the async space reclaim task calls btrfs_wait_on_delayed_iputs(), the block group reclaim task which is doing the data block group relocation, creates a delayed iput at replace_file_extents() (called when COWing leaves that have file extent items pointing to relocated data exten ---truncated---

Severity

5.5 (Medium)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2022-49702"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-667"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-02-26T07:01:45Z",
    "severity": "MODERATE"
  },
  "details": "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]  \u003cTASK\u003e\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]  \u003c/TASK\u003e\n[629724.516694] task:umount          state:D stack:    0 pid:719055 ppid:695412 flags:0x00004000\n[629724.518269] Call Trace:\n[629724.518746]  \u003cTASK\u003e\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]  \u003c/TASK\u003e\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\u0027s 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---",
  "id": "GHSA-6hq8-g74x-24q3",
  "modified": "2025-10-24T18:30:57Z",
  "published": "2025-10-24T18:30:56Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-49702"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/31e70e527806c546a72262f2fc3d982ee23c42d3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/341d33128a940c6634175dcb6ca92dc454cfa7d2"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9fadb11f1295289e0da4d3342ecb6b92c1c99540"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2022-49702 (GCVE-0-2022-49702)

Vulnerability from cvelistv5 – Published: 2025-02-26 02:24 – Updated: 2026-05-11 19:05

Title

btrfs: fix hang during unmount when block group reclaim task is running

Summary

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix hang during unmount when block group reclaim task is running When we start an unmount, at close_ctree(), if we have the reclaim task running and in the middle of a data block group relocation, we can trigger a deadlock when stopping an async reclaim task, producing a trace like the following: [629724.498185] task:kworker/u16:7 state:D stack: 0 pid:681170 ppid: 2 flags:0x00004000 [629724.499760] Workqueue: events_unbound btrfs_async_reclaim_metadata_space [btrfs] [629724.501267] Call Trace: [629724.501759] <TASK> [629724.502174] __schedule+0x3cb/0xed0 [629724.502842] schedule+0x4e/0xb0 [629724.503447] btrfs_wait_on_delayed_iputs+0x7c/0xc0 [btrfs] [629724.504534] ? prepare_to_wait_exclusive+0xc0/0xc0 [629724.505442] flush_space+0x423/0x630 [btrfs] [629724.506296] ? rcu_read_unlock_trace_special+0x20/0x50 [629724.507259] ? lock_release+0x220/0x4a0 [629724.507932] ? btrfs_get_alloc_profile+0xb3/0x290 [btrfs] [629724.508940] ? do_raw_spin_unlock+0x4b/0xa0 [629724.509688] btrfs_async_reclaim_metadata_space+0x139/0x320 [btrfs] [629724.510922] process_one_work+0x252/0x5a0 [629724.511694] ? process_one_work+0x5a0/0x5a0 [629724.512508] worker_thread+0x52/0x3b0 [629724.513220] ? process_one_work+0x5a0/0x5a0 [629724.514021] kthread+0xf2/0x120 [629724.514627] ? kthread_complete_and_exit+0x20/0x20 [629724.515526] ret_from_fork+0x22/0x30 [629724.516236] </TASK> [629724.516694] task:umount state:D stack: 0 pid:719055 ppid:695412 flags:0x00004000 [629724.518269] Call Trace: [629724.518746] <TASK> [629724.519160] __schedule+0x3cb/0xed0 [629724.519835] schedule+0x4e/0xb0 [629724.520467] schedule_timeout+0xed/0x130 [629724.521221] ? lock_release+0x220/0x4a0 [629724.521946] ? lock_acquired+0x19c/0x420 [629724.522662] ? trace_hardirqs_on+0x1b/0xe0 [629724.523411] __wait_for_common+0xaf/0x1f0 [629724.524189] ? usleep_range_state+0xb0/0xb0 [629724.524997] __flush_work+0x26d/0x530 [629724.525698] ? flush_workqueue_prep_pwqs+0x140/0x140 [629724.526580] ? lock_acquire+0x1a0/0x310 [629724.527324] __cancel_work_timer+0x137/0x1c0 [629724.528190] close_ctree+0xfd/0x531 [btrfs] [629724.529000] ? evict_inodes+0x166/0x1c0 [629724.529510] generic_shutdown_super+0x74/0x120 [629724.530103] kill_anon_super+0x14/0x30 [629724.530611] btrfs_kill_super+0x12/0x20 [btrfs] [629724.531246] deactivate_locked_super+0x31/0xa0 [629724.531817] cleanup_mnt+0x147/0x1c0 [629724.532319] task_work_run+0x5c/0xa0 [629724.532984] exit_to_user_mode_prepare+0x1a6/0x1b0 [629724.533598] syscall_exit_to_user_mode+0x16/0x40 [629724.534200] do_syscall_64+0x48/0x90 [629724.534667] entry_SYSCALL_64_after_hwframe+0x44/0xae [629724.535318] RIP: 0033:0x7fa2b90437a7 [629724.535804] RSP: 002b:00007ffe0b7e4458 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 [629724.536912] RAX: 0000000000000000 RBX: 00007fa2b9182264 RCX: 00007fa2b90437a7 [629724.538156] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000555d6cf20dd0 [629724.539053] RBP: 0000555d6cf20ba0 R08: 0000000000000000 R09: 00007ffe0b7e3200 [629724.539956] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [629724.540883] R13: 0000555d6cf20dd0 R14: 0000555d6cf20cb0 R15: 0000000000000000 [629724.541796] </TASK> This happens because: 1) Before entering close_ctree() we have the async block group reclaim task running and relocating a data block group; 2) There's an async metadata (or data) space reclaim task running; 3) We enter close_ctree() and park the cleaner kthread; 4) The async space reclaim task is at flush_space() and runs all the existing delayed iputs; 5) Before the async space reclaim task calls btrfs_wait_on_delayed_iputs(), the block group reclaim task which is doing the data block group relocation, creates a delayed iput at replace_file_extents() (called when COWing leaves that have file extent items pointing to relocated data exten ---truncated---

Severity

No CVSS data available.

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6854 records in the last 180 days details

References

3 references

URL	Tags
https://git.kernel.org/stable/c/341d33128a940c663…
https://git.kernel.org/stable/c/9fadb11f1295289e0…
https://git.kernel.org/stable/c/31e70e527806c546a…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 18bb8bbf13c1839b43c9e09e76d397b753989af2 , < 341d33128a940c6634175dcb6ca92dc454cfa7d2 (git) Affected: 18bb8bbf13c1839b43c9e09e76d397b753989af2 , < 9fadb11f1295289e0da4d3342ecb6b92c1c99540 (git) Affected: 18bb8bbf13c1839b43c9e09e76d397b753989af2 , < 31e70e527806c546a72262f2fc3d982ee23c42d3 (git)
Linux	Linux	Affected: 5.13 Unaffected: 0 , < 5.13 (semver) Unaffected: 5.15.51 , ≤ 5.15.* (semver) Unaffected: 5.18.8 , ≤ 5.18.* (semver) Unaffected: 5.19 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/btrfs/disk-io.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "341d33128a940c6634175dcb6ca92dc454cfa7d2",
              "status": "affected",
              "version": "18bb8bbf13c1839b43c9e09e76d397b753989af2",
              "versionType": "git"
            },
            {
              "lessThan": "9fadb11f1295289e0da4d3342ecb6b92c1c99540",
              "status": "affected",
              "version": "18bb8bbf13c1839b43c9e09e76d397b753989af2",
              "versionType": "git"
            },
            {
              "lessThan": "31e70e527806c546a72262f2fc3d982ee23c42d3",
              "status": "affected",
              "version": "18bb8bbf13c1839b43c9e09e76d397b753989af2",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/btrfs/disk-io.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.13"
            },
            {
              "lessThan": "5.13",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.51",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.18.*",
              "status": "unaffected",
              "version": "5.18.8",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "5.19",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.51",
                  "versionStartIncluding": "5.13",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.18.8",
                  "versionStartIncluding": "5.13",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.19",
                  "versionStartIncluding": "5.13",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "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]  \u003cTASK\u003e\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]  \u003c/TASK\u003e\n[629724.516694] task:umount          state:D stack:    0 pid:719055 ppid:695412 flags:0x00004000\n[629724.518269] Call Trace:\n[629724.518746]  \u003cTASK\u003e\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]  \u003c/TASK\u003e\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\u0027s 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---"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-11T19:05:05.519Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/341d33128a940c6634175dcb6ca92dc454cfa7d2"
        },
        {
          "url": "https://git.kernel.org/stable/c/9fadb11f1295289e0da4d3342ecb6b92c1c99540"
        },
        {
          "url": "https://git.kernel.org/stable/c/31e70e527806c546a72262f2fc3d982ee23c42d3"
        }
      ],
      "title": "btrfs: fix hang during unmount when block group reclaim task is running",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2022-49702",
    "datePublished": "2025-02-26T02:24:22.030Z",
    "dateReserved": "2025-02-26T02:21:30.443Z",
    "dateUpdated": "2026-05-11T19:05:05.519Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

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