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CVE-2024-56549

In the Linux kernel, the following vulnerability has been resolved: cachefiles: Fix NULL pointer dereference in object->file At present, the object->file has the NULL…

Published Dec 27, 2024 · updated Oct 15, 2026 · linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: cachefiles: Fix NULL pointer dereference in object->file At present, the object->file has the NULL pointer dereference problem in ondemand-mode. The root cause is that the allocated fd and object->file lifetime are inconsistent, and the user-space invocation to anon_fd uses object->file. Following is the process that triggers the issue: [write fd] [umount] cachefiles_ondemand_fd_write_iter fscache_cookie_state_machine cachefiles_withdraw_cookie if (!file) return -ENOBUFS cachefiles_clean_up_object cachefiles_unmark_inode_in_use fput(object->file) object->file = NULL // file NULL pointer dereference! __cachefiles_write(..., file, ...) Fix this issue by add an additional reference count to the object->file before write/llseek, and decrement after it finished.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Dec 27, 2024 · NIST NVD

    Detected

    In the Linux kernel, the following vulnerability has been resolved: cachefiles: Fix NULL pointer dereference in object->file At present, the object->file has the NULL pointer dereference problem in ondemand-mode. The root cause is that the allocated fd and object->file lifetime are inconsistent, and the user-space invocation to anon_fd uses object->file. Following is the process that triggers the

  2. Oct 15, 2026 · NIST NVD

    Updated

    In the Linux kernel, the following vulnerability has been resolved: cachefiles: Fix NULL pointer dereference in object->file At present, the object->file has the NULL pointer dereference problem in ondemand-mode. The root cause is that the allocated fd and object->file lifetime are inconsistent, and the user-space invocation to anon_fd uses object->file. Following is the process that triggers the

Affected

  • cpe linux/linux kernelversion unspecified

Sources

  • CVE.orgVulnerability recordCVE-2024-56549

    Official CVE identifier

    cve.org
  • NIST NVDVulnerability recordCVE-2024-56549

    In the Linux kernel, the following vulnerability has been resolved: cachefiles: Fix NULL pointer dereference in object->file At present, the object->file has the NULL pointer dereference problem in ondemand-mode. The root cause is that the allocated fd and object->file lifetime

    nvd.nist.gov

References