{ "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-2024-57896", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2024-57896", "idYear": 2024, "status": "PUBLISHED", "publishedAt": "2025-01-15T13:05:48.310Z", "updatedAt": "2026-08-05T11:46:49.998Z", "importedAt": "2026-10-24T01:57:20.494Z", "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: flush delalloc workers queue before stopping cleaner kthread during unmount", "summary": "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 \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 \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---", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "fd340d0f68cc87badfc9efcb226f23a5428826a0", "status": "affected", "versionType": "git", "lessThan": "a2718ed1eb8c3611b63f8933c7e68c8821fe2808" }, { "version": "fd340d0f68cc87badfc9efcb226f23a5428826a0", "status": "affected", "versionType": "git", "lessThan": "63f4b594a688bf922e8691f0784679aa7af7988c" }, { "version": "fd340d0f68cc87badfc9efcb226f23a5428826a0", "status": "affected", "versionType": "git", "lessThan": "1ea629e7bb2fb40555e5e01a1b5095df31287017" }, { "version": "fd340d0f68cc87badfc9efcb226f23a5428826a0", "status": "affected", "versionType": "git", "lessThan": "35916b2f96505a18dc7242a115611b718d9de725" }, { "version": "fd340d0f68cc87badfc9efcb226f23a5428826a0", "status": "affected", "versionType": "git", "lessThan": "d77a3a99b53d12c061c007cdc96df38825dee476" }, { "version": "fd340d0f68cc87badfc9efcb226f23a5428826a0", "status": "affected", "versionType": "git", "lessThan": "f10bef73fb355e3fc85e63a50386798be68ff486" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "5.0", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "5.0" }, { "version": "5.10.233", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.176", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.124", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.70", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.9", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.13", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }