Copyright © 2012 Red Hat, Inc. All rights reserved. Low 2026-06-24T00:00:00 kernel: fwctl: Fix class init ordering to avoid NULL pointer dereference on device removal 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CWE-824

In the Linux kernel, the following vulnerability has been resolved: fwctl: Fix class init ordering to avoid NULL pointer dereference on device removal CXL is linked before fwctl in drivers/Makefile. Both use `module_init, so `cxl_pci_driver_init()` runs first. When `cxl_pci_probe()` calls `fwctl_register()` and then `device_add()`, fwctl_class is not yet registered because fwctl_init() hasn't run, causing `class_to_subsys()` to return NULL and skip knode_class initialization. On device removal, `class_to_subsys()` returns non-NULL, and `device_del()` calls `klist_del()` on the uninitialized knode, triggering a NULL pointer dereference.

A flaw was found in the Linux kernel's `fwctl` module. An issue with the class initialization ordering can lead to a null pointer dereference when a device is removed. This can cause a system crash, resulting in a Denial of Service (DoS).

Red Hat Enterprise Linux 10 Fix deferred kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Not affected kernel Red Hat Enterprise Linux 8 Not affected kernel-rt Red Hat Enterprise Linux 9 Not affected kernel Red Hat Enterprise Linux 9 Not affected kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-53042 https://nvd.nist.gov/vuln/detail/CVE-2026-53042 https://lore.kernel.org/linux-cve-announce/2026062457-CVE-2026-53042-9758@gregkh/T