CVE intelligence and bounded remediation

CVE-2024-57896 — Linux Linux Kernel security vulnerability

High CVSS 7.8

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.…

Severity
High
CVSS
7.8 (3.1)
Published
2025-01-15
CISA KEV
Not currently listed
Ecosystem
linux/kernel
Weaknesses
CWE-416

Affected products

  • linux / linux_kernel
  • linux / linux_kernel / 6.13

Showing 2 representative product identities from 7 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Use-after-free, double free, and expired resource use

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Trace ownership, references, callbacks, asynchronous tasks, and teardown paths around the affected object or resource.
  • Identify reachable inputs and timing or state transitions that can release the object while references remain.
  • Confirm affected builds, allocators, feature flags, architectures, and process privileges.

Remediate safely

  • Apply the maintained ownership or lifetime fix and rebuild all artifacts containing the affected native code.
  • Use explicit ownership, safe reference management, cancellation and join semantics, and idempotent teardown.
  • Add deterministic lifetime tests plus isolated sanitizer and concurrency coverage for shutdown and error paths.

Authoritative sources

Complete CVE record and remediation plan

The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.