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CVE-2024-57896 (GCVE-0-2024-57896)

Vulnerability from cvelistv5 – Published: 2025-01-15 13:05 – Updated: 2026-08-05 11:46
VLAI
Title
btrfs: flush delalloc workers queue before stopping cleaner kthread during unmount
Summary
In the Linux kernel, the following vulnerability has been resolved: btrfs: flush delalloc workers queue before stopping cleaner kthread during unmount During the unmount path, at close_ctree(), we first stop the cleaner kthread, using kthread_stop() which frees the associated task_struct, and then stop and destroy all the work queues. However after we stopped the cleaner we may still have a worker from the delalloc_workers queue running inode.c:submit_compressed_extents(), which calls btrfs_add_delayed_iput(), which in turn tries to wake up the cleaner kthread - which was already destroyed before, resulting in a use-after-free on the task_struct. Syzbot reported this with the following stack traces: BUG: KASAN: slab-use-after-free in __lock_acquire+0x78/0x2100 kernel/locking/lockdep.c:5089 Read of size 8 at addr ffff8880259d2818 by task kworker/u8:3/52 CPU: 1 UID: 0 PID: 52 Comm: kworker/u8:3 Not tainted 6.13.0-rc1-syzkaller-00002-gcdd30ebb1b9f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: btrfs-delalloc btrfs_work_helper Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 __lock_acquire+0x78/0x2100 kernel/locking/lockdep.c:5089 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline] try_to_wake_up+0xc2/0x1470 kernel/sched/core.c:4205 submit_compressed_extents+0xdf/0x16e0 fs/btrfs/inode.c:1615 run_ordered_work fs/btrfs/async-thread.c:288 [inline] btrfs_work_helper+0x96f/0xc40 fs/btrfs/async-thread.c:324 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Allocated by task 2: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4104 [inline] slab_alloc_node mm/slub.c:4153 [inline] kmem_cache_alloc_node_noprof+0x1d9/0x380 mm/slub.c:4205 alloc_task_struct_node kernel/fork.c:180 [inline] dup_task_struct+0x57/0x8c0 kernel/fork.c:1113 copy_process+0x5d1/0x3d50 kernel/fork.c:2225 kernel_clone+0x223/0x870 kernel/fork.c:2807 kernel_thread+0x1bc/0x240 kernel/fork.c:2869 create_kthread kernel/kthread.c:412 [inline] kthreadd+0x60d/0x810 kernel/kthread.c:767 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 24: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2338 [inline] slab_free mm/slub.c:4598 [inline] kmem_cache_free+0x195/0x410 mm/slub.c:4700 put_task_struct include/linux/sched/task.h:144 [inline] delayed_put_task_struct+0x125/0x300 kernel/exit.c:227 rcu_do_batch kernel/rcu/tree.c:2567 [inline] rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2823 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:943 ---truncated---
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-02-11 15:40 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: fd340d0f68cc87badfc9efcb226f23a5428826a0 , < a2718ed1eb8c3611b63f8933c7e68c8821fe2808 (git)
Affected: fd340d0f68cc87badfc9efcb226f23a5428826a0 , < 63f4b594a688bf922e8691f0784679aa7af7988c (git)
Affected: fd340d0f68cc87badfc9efcb226f23a5428826a0 , < 1ea629e7bb2fb40555e5e01a1b5095df31287017 (git)
Affected: fd340d0f68cc87badfc9efcb226f23a5428826a0 , < 35916b2f96505a18dc7242a115611b718d9de725 (git)
Affected: fd340d0f68cc87badfc9efcb226f23a5428826a0 , < d77a3a99b53d12c061c007cdc96df38825dee476 (git)
Affected: fd340d0f68cc87badfc9efcb226f23a5428826a0 , < f10bef73fb355e3fc85e63a50386798be68ff486 (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.0
Unaffected: 0 , < 5.0 (semver)
Unaffected: 5.10.233 , ≤ 5.10.* (semver)
Unaffected: 5.15.176 , ≤ 5.15.* (semver)
Unaffected: 6.1.124 , ≤ 6.1.* (semver)
Unaffected: 6.6.70 , ≤ 6.6.* (semver)
Unaffected: 6.12.9 , ≤ 6.12.* (semver)
Unaffected: 6.13 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: flush delalloc workers queue before stopping cleaner kthread during unmount\n\nDuring the unmount path, at close_ctree(), we first stop the cleaner\nkthread, using kthread_stop() which frees the associated task_struct, and\nthen stop and destroy all the work queues. However after we stopped the\ncleaner we may still have a worker from the delalloc_workers queue running\ninode.c:submit_compressed_extents(), which calls btrfs_add_delayed_iput(),\nwhich in turn tries to wake up the cleaner kthread - which was already\ndestroyed before, resulting in a use-after-free on the task_struct.\n\nSyzbot reported this with the following stack traces:\n\n  BUG: KASAN: slab-use-after-free in __lock_acquire+0x78/0x2100 kernel/locking/lockdep.c:5089\n  Read of size 8 at addr ffff8880259d2818 by task kworker/u8:3/52\n\n  CPU: 1 UID: 0 PID: 52 Comm: kworker/u8:3 Not tainted 6.13.0-rc1-syzkaller-00002-gcdd30ebb1b9f #0\n  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024\n  Workqueue: btrfs-delalloc btrfs_work_helper\n  Call Trace:\n   \u003cTASK\u003e\n   __dump_stack lib/dump_stack.c:94 [inline]\n   dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120\n   print_address_description mm/kasan/report.c:378 [inline]\n   print_report+0x169/0x550 mm/kasan/report.c:489\n   kasan_report+0x143/0x180 mm/kasan/report.c:602\n   __lock_acquire+0x78/0x2100 kernel/locking/lockdep.c:5089\n   lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849\n   __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]\n   _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162\n   class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline]\n   try_to_wake_up+0xc2/0x1470 kernel/sched/core.c:4205\n   submit_compressed_extents+0xdf/0x16e0 fs/btrfs/inode.c:1615\n   run_ordered_work fs/btrfs/async-thread.c:288 [inline]\n   btrfs_work_helper+0x96f/0xc40 fs/btrfs/async-thread.c:324\n   process_one_work kernel/workqueue.c:3229 [inline]\n   process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310\n   worker_thread+0x870/0xd30 kernel/workqueue.c:3391\n   kthread+0x2f0/0x390 kernel/kthread.c:389\n   ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147\n   ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244\n   \u003c/TASK\u003e\n\n  Allocated by task 2:\n   kasan_save_stack mm/kasan/common.c:47 [inline]\n   kasan_save_track+0x3f/0x80 mm/kasan/common.c:68\n   unpoison_slab_object mm/kasan/common.c:319 [inline]\n   __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345\n   kasan_slab_alloc include/linux/kasan.h:250 [inline]\n   slab_post_alloc_hook mm/slub.c:4104 [inline]\n   slab_alloc_node mm/slub.c:4153 [inline]\n   kmem_cache_alloc_node_noprof+0x1d9/0x380 mm/slub.c:4205\n   alloc_task_struct_node kernel/fork.c:180 [inline]\n   dup_task_struct+0x57/0x8c0 kernel/fork.c:1113\n   copy_process+0x5d1/0x3d50 kernel/fork.c:2225\n   kernel_clone+0x223/0x870 kernel/fork.c:2807\n   kernel_thread+0x1bc/0x240 kernel/fork.c:2869\n   create_kthread kernel/kthread.c:412 [inline]\n   kthreadd+0x60d/0x810 kernel/kthread.c:767\n   ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147\n   ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244\n\n  Freed by task 24:\n   kasan_save_stack mm/kasan/common.c:47 [inline]\n   kasan_save_track+0x3f/0x80 mm/kasan/common.c:68\n   kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582\n   poison_slab_object mm/kasan/common.c:247 [inline]\n   __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264\n   kasan_slab_free include/linux/kasan.h:233 [inline]\n   slab_free_hook mm/slub.c:2338 [inline]\n   slab_free mm/slub.c:4598 [inline]\n   kmem_cache_free+0x195/0x410 mm/slub.c:4700\n   put_task_struct include/linux/sched/task.h:144 [inline]\n   delayed_put_task_struct+0x125/0x300 kernel/exit.c:227\n   rcu_do_batch kernel/rcu/tree.c:2567 [inline]\n   rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2823\n   handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:554\n   run_ksoftirqd+0xca/0x130 kernel/softirq.c:943\n  \n---truncated---"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The attack requires local access to write compressed data to a mounted btrfs filesystem and the local unmount path (`umount(2)` \u2192 `close_ctree()`); there is no remote protocol handler involved.\nAC:L - The attacker fully controls one side of the race and can keep the `delalloc_workers` queue continuously saturated with compressed writeback so that a worker is essentially always in flight, making the UAF fire on any unmount rather than requiring a narrow timing window; where the attacker can also trigger the unmount (removable media via udisks2, container teardown) they control both sides.\nPR:L - Generating the compressed delalloc work needs only an unprivileged user with write access to a btrfs mount \u2014 per-inode compression is settable by the file owner via `chattr +c` (`inode_owner_or_capable`), and many distros mount with `compress=zstd` by default.\nUI:N - No victim action is needed; the unmount that closes the race occurs automatically at shutdown, on container teardown, or on media eject, and in the removable-media case the attacker performs it themselves.\nS:U - The use-after-free is on a kernel `task_struct` and impacts only the kernel\u0027s own security authority, with no crossing of a VM, IOMMU, or sandbox boundary.\nC:H - The freed `task_struct` slab object can be reallocated with attacker-groomed content, and the wakeup path reads scheduler fields and pointers from it, giving a path to kernel memory disclosure.\nI:H - `try_to_wake_up()` writes into the freed object (`pi_lock` acquisition, `__state`/`on_rq` updates) and performs indirect calls through `p-\u003esched_class`, providing write and control-flow-hijack primitives on a sprayable slab.\nA:H - The bug is a KASAN-confirmed slab-use-after-free reported by syzbot that reliably oopses or panics the kernel during unmount."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T11:46:49.998Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/a2718ed1eb8c3611b63f8933c7e68c8821fe2808"
        },
        {
          "url": "https://git.kernel.org/stable/c/63f4b594a688bf922e8691f0784679aa7af7988c"
        },
        {
          "url": "https://git.kernel.org/stable/c/1ea629e7bb2fb40555e5e01a1b5095df31287017"
        },
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          "url": "https://git.kernel.org/stable/c/35916b2f96505a18dc7242a115611b718d9de725"
        },
        {
          "url": "https://git.kernel.org/stable/c/d77a3a99b53d12c061c007cdc96df38825dee476"
        },
        {
          "url": "https://git.kernel.org/stable/c/f10bef73fb355e3fc85e63a50386798be68ff486"
        }
      ],
      "title": "btrfs: flush delalloc workers queue before stopping cleaner kthread during unmount",
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  "cveMetadata": {
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    "assignerShortName": "Linux",
    "cveId": "CVE-2024-57896",
    "datePublished": "2025-01-15T13:05:48.310Z",
    "dateReserved": "2025-01-11T14:45:42.029Z",
    "dateUpdated": "2026-08-05T11:46:49.998Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2024-57896",
      "date": "2026-09-16",
      "epss": "0.00213",
      "percentile": "0.11804"
    },
    "microsoft_vex": {
      "current_release_date": "2026-02-18T02:22:05.000Z",
      "cve": "CVE-2024-57896",
      "id": "msrc_CVE-2024-57896",
      "initial_release_date": "2025-01-02T00:00:00.000Z",
      "product_status:fixed": "4",
      "product_status:known_affected": "4",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "btrfs: flush delalloc workers queue before stopping cleaner kthread during unmount",
      "url": "https://msrc.microsoft.com/csaf/vex/2025/msrc_cve-2024-57896.json",
      "version": "3"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2024-57896\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2025-01-15T13:15:14.200\",\"lastModified\":\"2026-06-17T08:14:10.200\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nbtrfs: flush delalloc workers queue before stopping cleaner kthread during unmount\\n\\nDuring the unmount path, at close_ctree(), we first stop the cleaner\\nkthread, using kthread_stop() which frees the associated task_struct, and\\nthen stop and destroy all the work queues. However after we stopped the\\ncleaner we may still have a worker from the delalloc_workers queue running\\ninode.c:submit_compressed_extents(), which calls btrfs_add_delayed_iput(),\\nwhich in turn tries to wake up the cleaner kthread - which was already\\ndestroyed before, resulting in a use-after-free on the task_struct.\\n\\nSyzbot reported this with the following stack traces:\\n\\n  BUG: KASAN: slab-use-after-free in __lock_acquire+0x78/0x2100 kernel/locking/lockdep.c:5089\\n  Read of size 8 at addr ffff8880259d2818 by task kworker/u8:3/52\\n\\n  CPU: 1 UID: 0 PID: 52 Comm: kworker/u8:3 Not tainted 6.13.0-rc1-syzkaller-00002-gcdd30ebb1b9f #0\\n  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024\\n  Workqueue: btrfs-delalloc btrfs_work_helper\\n  Call Trace:\\n   \u003cTASK\u003e\\n   __dump_stack lib/dump_stack.c:94 [inline]\\n   dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120\\n   print_address_description mm/kasan/report.c:378 [inline]\\n   print_report+0x169/0x550 mm/kasan/report.c:489\\n   kasan_report+0x143/0x180 mm/kasan/report.c:602\\n   __lock_acquire+0x78/0x2100 kernel/locking/lockdep.c:5089\\n   lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849\\n   __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]\\n   _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162\\n   class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline]\\n   try_to_wake_up+0xc2/0x1470 kernel/sched/core.c:4205\\n   submit_compressed_extents+0xdf/0x16e0 fs/btrfs/inode.c:1615\\n   run_ordered_work fs/btrfs/async-thread.c:288 [inline]\\n   btrfs_work_helper+0x96f/0xc40 fs/btrfs/async-thread.c:324\\n   process_one_work kernel/workqueue.c:3229 [inline]\\n   process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310\\n   worker_thread+0x870/0xd30 kernel/workqueue.c:3391\\n   kthread+0x2f0/0x390 kernel/kthread.c:389\\n   ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147\\n   ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244\\n   \u003c/TASK\u003e\\n\\n  Allocated by task 2:\\n   kasan_save_stack mm/kasan/common.c:47 [inline]\\n   kasan_save_track+0x3f/0x80 mm/kasan/common.c:68\\n   unpoison_slab_object mm/kasan/common.c:319 [inline]\\n   __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345\\n   kasan_slab_alloc include/linux/kasan.h:250 [inline]\\n   slab_post_alloc_hook mm/slub.c:4104 [inline]\\n   slab_alloc_node mm/slub.c:4153 [inline]\\n   kmem_cache_alloc_node_noprof+0x1d9/0x380 mm/slub.c:4205\\n   alloc_task_struct_node kernel/fork.c:180 [inline]\\n   dup_task_struct+0x57/0x8c0 kernel/fork.c:1113\\n   copy_process+0x5d1/0x3d50 kernel/fork.c:2225\\n   kernel_clone+0x223/0x870 kernel/fork.c:2807\\n   kernel_thread+0x1bc/0x240 kernel/fork.c:2869\\n   create_kthread kernel/kthread.c:412 [inline]\\n   kthreadd+0x60d/0x810 kernel/kthread.c:767\\n   ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147\\n   ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244\\n\\n  Freed by task 24:\\n   kasan_save_stack mm/kasan/common.c:47 [inline]\\n   kasan_save_track+0x3f/0x80 mm/kasan/common.c:68\\n   kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582\\n   poison_slab_object mm/kasan/common.c:247 [inline]\\n   __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264\\n   kasan_slab_free include/linux/kasan.h:233 [inline]\\n   slab_free_hook mm/slub.c:2338 [inline]\\n   slab_free mm/slub.c:4598 [inline]\\n   kmem_cache_free+0x195/0x410 mm/slub.c:4700\\n   put_task_struct include/linux/sched/task.h:144 [inline]\\n   delayed_put_task_struct+0x125/0x300 kernel/exit.c:227\\n   rcu_do_batch kernel/rcu/tree.c:2567 [inline]\\n   rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2823\\n   handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:554\\n   run_ksoftirqd+0xca/0x130 kernel/softirq.c:943\\n  \\n---truncated---\"},{\"lang\":\"es\",\"value\":\"En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: btrfs: vaciar la cola de trabajadores delalloc antes de detener el kthread del limpiador durante el desmontaje Durante la ruta de desmontaje, en close_ctree(), primero detenemos el kthread del limpiador, utilizando kthread_stop() que libera el task_struct asociado, y luego detenemos y destruimos todas las colas de trabajo. Sin embargo, despu\u00e9s de detener el limpiador, es posible que a\u00fan tengamos un trabajador de la cola delalloc_workers ejecutando inode.c:submit_compressed_extents(), que llama a btrfs_add_delayed_iput(), que a su vez intenta despertar el kthread del limpiador, que ya se destruy\u00f3 antes, lo que resulta en un uso despu\u00e9s de la liberaci\u00f3n en el task_struct. Syzbot inform\u00f3 esto con los siguientes seguimientos de pila: ERROR: KASAN: slab-use-after-free en __lock_acquire+0x78/0x2100 kernel/locking/lockdep.c:5089 Lectura de tama\u00f1o 8 en la direcci\u00f3n ffff8880259d2818 por la tarea kworker/u8:3/52 CPU: 1 UID: 0 PID: 52 Comm: kworker/u8:3 No contaminado 6.13.0-rc1-syzkaller-00002-gcdd30ebb1b9f #0 Nombre del hardware: Google Google Compute Engine/Google Compute Engine, BIOS Google 13/09/2024 Cola de trabajo: btrfs-delalloc btrfs_work_helper Seguimiento de llamadas:  __dump_stack lib/dump_stack.c:94 [en l\u00ednea] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [en l\u00ednea] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 __lock_acquire+0x78/0x2100 kernel/locking/lockdep.c:5089 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __raw_spin_lock_irqsave incluir/linux/spinlock_api_smp.h:110 [en l\u00ednea] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [en l\u00ednea] try_to_wake_up+0xc2/0x1470 kernel/sched/core.c:4205 submit_compressed_extents+0xdf/0x16e0 fs/btrfs/inode.c:1615 run_ordered_work fs/btrfs/async-thread.c:288 [en l\u00ednea] btrfs_work_helper+0x96f/0xc40 fs/btrfs/async-thread.c:324 process_one_work kernel/workqueue.c:3229 [en l\u00ednea] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 Asignado por la tarea 2: kasan_save_stack mm/kasan/common.c:47 [en l\u00ednea] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [en l\u00ednea] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [en l\u00ednea] gancho de alloc de publicaci\u00f3n de losa mm/slub.c:4104 [en l\u00ednea] nodo de alloc de losa mm/slub.c:4153 [en l\u00ednea] nodo de alloc de cach\u00e9 kmem_noprof+0x1d9/0x380 mm/slub.c:4205 nodo de estructura de tareas de asignaci\u00f3n kernel/fork.c:180 [en l\u00ednea] estructura de tareas dup+0x57/0x8c0 kernel/fork.c:1113 proceso de copia+0x5d1/0x3d50 kernel/fork.c:2225 clon de kernel+0x223/0x870 kernel/fork.c:2807 kernel_thread+0x1bc/0x240 kernel/fork.c:2869 create_kthread kernel/kthread.c:412 [en l\u00ednea] kthreadd+0x60d/0x810 kernel/kthread.c:767 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Liberado por la tarea 24: kasan_save_stack mm/kasan/common.c:47 [en l\u00ednea] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582 poison_slab_object mm/kasan/common.c:247 [en l\u00ednea] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [en l\u00ednea] gancho slab_free mm/slub.c:2338 [en l\u00ednea] slab_free mm/slub.c:4598 [en l\u00ednea] kmem_cache_free+0x195/0x410 mm/slub.c:4700 put_task_struct include/linux/sched/task.h:144 [en l\u00ednea] delayed_put_task_struct+0x125/0x300 kernel/exit.c:227 rcu_do_batch kernel/rcu/tree.c:2567 [en l\u00ednea] rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2823 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:943 ---truncado---\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"fs/btrfs/disk-io.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"fd340d0f68cc87badfc9efcb226f23a5428826a0\",\"lessThan\":\"a2718ed1eb8c3611b63f8933c7e68c8821fe2808\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"fd340d0f68cc87badfc9efcb226f23a5428826a0\",\"lessThan\":\"63f4b594a688bf922e8691f0784679aa7af7988c\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"fd340d0f68cc87badfc9efcb226f23a5428826a0\",\"lessThan\":\"1ea629e7bb2fb40555e5e01a1b5095df31287017\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"fd340d0f68cc87badfc9efcb226f23a5428826a0\",\"lessThan\":\"35916b2f96505a18dc7242a115611b718d9de725\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"fd340d0f68cc87badfc9efcb226f23a5428826a0\",\"lessThan\":\"d77a3a99b53d12c061c007cdc96df38825dee476\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"fd340d0f68cc87badfc9efcb226f23a5428826a0\",\"lessThan\":\"f10bef73fb355e3fc85e63a50386798be68ff486\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"fs/btrfs/disk-io.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"5.0\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"5.0\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.233\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.176\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.124\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.70\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.9\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.13\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9},{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2025-02-11T15:40:57.951586Z\",\"id\":\"CVE-2024-57896\",\"options\":[{\"exploitation\":\"none\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"total\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-416\"}]},{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-416\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionEndExcluding\":\"5.10.233\",\"matchCriteriaId\":\"B108BF34-DC4E-4111-9959-D325A6BD3B57\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.11\",\"versionEndExcluding\":\"5.15.176\",\"matchCriteriaId\":\"DDBD8FC6-2357-4347-BFA1-B4A4A3039F35\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.16\",\"versionEndExcluding\":\"6.1.124\",\"matchCriteriaId\":\"1B69CE1B-5219-42EB-B7DD-7E7D7F1DB032\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.2\",\"versionEndExcluding\":\"6.6.70\",\"matchCriteriaId\":\"51E6CFF2-92AA-4936-95AB-2D068168A696\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.7\",\"versionEndExcluding\":\"6.12.9\",\"matchCriteriaId\":\"1D13AF97-FFED-4B68-906D-CFE38D0B88DD\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:*\",\"matchCriteriaId\":\"62567B3C-6CEE-46D0-BC2E-B3717FBF7D13\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:*\",\"matchCriteriaId\":\"5A073481-106D-4B15-B4C7-FB0213B8E1D4\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/1ea629e7bb2fb40555e5e01a1b5095df31287017\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/35916b2f96505a18dc7242a115611b718d9de725\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/63f4b594a688bf922e8691f0784679aa7af7988c\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/a2718ed1eb8c3611b63f8933c7e68c8821fe2808\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/d77a3a99b53d12c061c007cdc96df38825dee476\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/f10bef73fb355e3fc85e63a50386798be68ff486\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\"},{\"url\":\"https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2025-11-21T13:51:29+00:00",
      "cve": "CVE-2024-57896",
      "id": "CVE-2024-57896",
      "initial_release_date": "2024-01-01T00:00:00+00:00",
      "product_status:known_affected": "42",
      "product_status:known_not_affected": "234",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: btrfs: flush delalloc workers queue before stopping cleaner kthread during unmount",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2024/cve-2024-57896.json",
      "version": "3"
    },
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CVE Program Container\", \"references\": [{\"url\": \"https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html\"}, {\"url\": \"https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html\"}], \"providerMetadata\": {\"orgId\": \"af854a3a-2127-422b-91ae-364da2661108\", \"shortName\": \"CVE\", \"dateUpdated\": \"2025-11-03T20:55:11.913Z\"}}, {\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 7.8, \"attackVector\": \"LOCAL\", \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"LOW\", \"confidentialityImpact\": \"HIGH\"}}, {\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2024-57896\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2025-02-11T15:40:57.951586Z\"}}}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-416\", \"description\": \"CWE-416 Use After Free\"}]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2025-02-11T15:40:59.294Z\"}}], \"cna\": {\"title\": \"btrfs: flush delalloc workers queue before stopping cleaner kthread during unmount\", \"metrics\": [{\"cvssV3_1\": {\"version\": \"3.1\", \"baseScore\": 7.8, \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"AV:L - The attack requires local access to write compressed data to a mounted btrfs filesystem and the local unmount path (`umount(2)` \\u2192 `close_ctree()`); there is no remote protocol handler involved.\\nAC:L - The attacker fully controls one side of the race and can keep the `delalloc_workers` queue continuously saturated with compressed writeback so that a worker is essentially always in flight, making the UAF fire on any unmount rather than requiring a narrow timing window; where the attacker can also trigger the unmount (removable media via udisks2, container teardown) they control both sides.\\nPR:L - Generating the compressed delalloc work needs only an unprivileged user with write access to a btrfs mount \\u2014 per-inode compression is settable by the file owner via `chattr +c` (`inode_owner_or_capable`), and many distros mount with `compress=zstd` by default.\\nUI:N - No victim action is needed; the unmount that closes the race occurs automatically at shutdown, on container teardown, or on media eject, and in the removable-media case the attacker performs it themselves.\\nS:U - The use-after-free is on a kernel `task_struct` and impacts only the kernel\u0027s own security authority, with no crossing of a VM, IOMMU, or sandbox boundary.\\nC:H - The freed `task_struct` slab object can be reallocated with attacker-groomed content, and the wakeup path reads scheduler fields and pointers from it, giving a path to kernel memory disclosure.\\nI:H - `try_to_wake_up()` writes into the freed object (`pi_lock` acquisition, `__state`/`on_rq` updates) and performs indirect calls through `p-\u003esched_class`, providing write and control-flow-hijack primitives on a sprayable slab.\\nA:H - The bug is a KASAN-confirmed slab-use-after-free reported by syzbot that reliably oopses or panics the kernel during unmount.\"}]}], \"affected\": [{\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"fd340d0f68cc87badfc9efcb226f23a5428826a0\", \"lessThan\": \"a2718ed1eb8c3611b63f8933c7e68c8821fe2808\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"fd340d0f68cc87badfc9efcb226f23a5428826a0\", \"lessThan\": \"63f4b594a688bf922e8691f0784679aa7af7988c\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"fd340d0f68cc87badfc9efcb226f23a5428826a0\", \"lessThan\": \"1ea629e7bb2fb40555e5e01a1b5095df31287017\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"fd340d0f68cc87badfc9efcb226f23a5428826a0\", \"lessThan\": \"35916b2f96505a18dc7242a115611b718d9de725\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"fd340d0f68cc87badfc9efcb226f23a5428826a0\", \"lessThan\": \"d77a3a99b53d12c061c007cdc96df38825dee476\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"fd340d0f68cc87badfc9efcb226f23a5428826a0\", \"lessThan\": \"f10bef73fb355e3fc85e63a50386798be68ff486\", \"versionType\": \"git\"}], \"programFiles\": [\"fs/btrfs/disk-io.c\"], \"defaultStatus\": \"unaffected\"}, {\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"5.0\"}, {\"status\": \"unaffected\", \"version\": \"0\", \"lessThan\": \"5.0\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"5.10.233\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.10.*\"}, {\"status\": \"unaffected\", \"version\": \"5.15.176\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.15.*\"}, {\"status\": \"unaffected\", \"version\": \"6.1.124\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.1.*\"}, {\"status\": \"unaffected\", \"version\": \"6.6.70\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.6.*\"}, {\"status\": \"unaffected\", \"version\": \"6.12.9\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.12.*\"}, {\"status\": \"unaffected\", \"version\": \"6.13\", \"versionType\": \"original_commit_for_fix\", \"lessThanOrEqual\": \"*\"}], \"programFiles\": [\"fs/btrfs/disk-io.c\"], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://git.kernel.org/stable/c/a2718ed1eb8c3611b63f8933c7e68c8821fe2808\"}, {\"url\": \"https://git.kernel.org/stable/c/63f4b594a688bf922e8691f0784679aa7af7988c\"}, {\"url\": \"https://git.kernel.org/stable/c/1ea629e7bb2fb40555e5e01a1b5095df31287017\"}, {\"url\": \"https://git.kernel.org/stable/c/35916b2f96505a18dc7242a115611b718d9de725\"}, {\"url\": \"https://git.kernel.org/stable/c/d77a3a99b53d12c061c007cdc96df38825dee476\"}, {\"url\": \"https://git.kernel.org/stable/c/f10bef73fb355e3fc85e63a50386798be68ff486\"}], \"x_generator\": {\"engine\": \"bippy-1.2.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\nbtrfs: flush delalloc workers queue before stopping cleaner kthread during unmount\\n\\nDuring the unmount path, at close_ctree(), we first stop the cleaner\\nkthread, using kthread_stop() which frees the associated task_struct, and\\nthen stop and destroy all the work queues. However after we stopped the\\ncleaner we may still have a worker from the delalloc_workers queue running\\ninode.c:submit_compressed_extents(), which calls btrfs_add_delayed_iput(),\\nwhich in turn tries to wake up the cleaner kthread - which was already\\ndestroyed before, resulting in a use-after-free on the task_struct.\\n\\nSyzbot reported this with the following stack traces:\\n\\n  BUG: KASAN: slab-use-after-free in __lock_acquire+0x78/0x2100 kernel/locking/lockdep.c:5089\\n  Read of size 8 at addr ffff8880259d2818 by task kworker/u8:3/52\\n\\n  CPU: 1 UID: 0 PID: 52 Comm: kworker/u8:3 Not tainted 6.13.0-rc1-syzkaller-00002-gcdd30ebb1b9f #0\\n  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024\\n  Workqueue: btrfs-delalloc btrfs_work_helper\\n  Call Trace:\\n   \u003cTASK\u003e\\n   __dump_stack lib/dump_stack.c:94 [inline]\\n   dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120\\n   print_address_description mm/kasan/report.c:378 [inline]\\n   print_report+0x169/0x550 mm/kasan/report.c:489\\n   kasan_report+0x143/0x180 mm/kasan/report.c:602\\n   __lock_acquire+0x78/0x2100 kernel/locking/lockdep.c:5089\\n   lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849\\n   __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]\\n   _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162\\n   class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline]\\n   try_to_wake_up+0xc2/0x1470 kernel/sched/core.c:4205\\n   submit_compressed_extents+0xdf/0x16e0 fs/btrfs/inode.c:1615\\n   run_ordered_work fs/btrfs/async-thread.c:288 [inline]\\n   btrfs_work_helper+0x96f/0xc40 fs/btrfs/async-thread.c:324\\n   process_one_work kernel/workqueue.c:3229 [inline]\\n   process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310\\n   worker_thread+0x870/0xd30 kernel/workqueue.c:3391\\n   kthread+0x2f0/0x390 kernel/kthread.c:389\\n   ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147\\n   ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244\\n   \u003c/TASK\u003e\\n\\n  Allocated by task 2:\\n   kasan_save_stack mm/kasan/common.c:47 [inline]\\n   kasan_save_track+0x3f/0x80 mm/kasan/common.c:68\\n   unpoison_slab_object mm/kasan/common.c:319 [inline]\\n   __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345\\n   kasan_slab_alloc include/linux/kasan.h:250 [inline]\\n   slab_post_alloc_hook mm/slub.c:4104 [inline]\\n   slab_alloc_node mm/slub.c:4153 [inline]\\n   kmem_cache_alloc_node_noprof+0x1d9/0x380 mm/slub.c:4205\\n   alloc_task_struct_node kernel/fork.c:180 [inline]\\n   dup_task_struct+0x57/0x8c0 kernel/fork.c:1113\\n   copy_process+0x5d1/0x3d50 kernel/fork.c:2225\\n   kernel_clone+0x223/0x870 kernel/fork.c:2807\\n   kernel_thread+0x1bc/0x240 kernel/fork.c:2869\\n   create_kthread kernel/kthread.c:412 [inline]\\n   kthreadd+0x60d/0x810 kernel/kthread.c:767\\n   ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147\\n   ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244\\n\\n  Freed by task 24:\\n   kasan_save_stack mm/kasan/common.c:47 [inline]\\n   kasan_save_track+0x3f/0x80 mm/kasan/common.c:68\\n   kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582\\n   poison_slab_object mm/kasan/common.c:247 [inline]\\n   __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264\\n   kasan_slab_free include/linux/kasan.h:233 [inline]\\n   slab_free_hook mm/slub.c:2338 [inline]\\n   slab_free mm/slub.c:4598 [inline]\\n   kmem_cache_free+0x195/0x410 mm/slub.c:4700\\n   put_task_struct include/linux/sched/task.h:144 [inline]\\n   delayed_put_task_struct+0x125/0x300 kernel/exit.c:227\\n   rcu_do_batch kernel/rcu/tree.c:2567 [inline]\\n   rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2823\\n   handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:554\\n   run_ksoftirqd+0xca/0x130 kernel/softirq.c:943\\n  \\n---truncated---\"}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"5.10.233\", \"versionStartIncluding\": \"5.0\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"5.15.176\", \"versionStartIncluding\": \"5.0\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.1.124\", \"versionStartIncluding\": \"5.0\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.6.70\", \"versionStartIncluding\": \"5.0\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.12.9\", \"versionStartIncluding\": \"5.0\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.13\", \"versionStartIncluding\": \"5.0\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"shortName\": \"Linux\", \"dateUpdated\": \"2026-08-05T11:46:49.998Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2024-57896\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-08-05T11:46:49.998Z\", \"dateReserved\": \"2025-01-11T14:45:42.029Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2025-01-15T13:05:48.310Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.