CVE-2025-21814: ptp: Ensure info->enable callback is always set
In the Linux kernel, the following vulnerability has been resolved:
ptp: Ensure info->enable callback is always set
The ioctl and sysfs handlers unconditionally call the ->enable callback. Not all drivers implement that callback, leading to NULL dereferences. Example of affected drivers: ptps390.c, ptpvclock.c and ptpmock.c.
Instead use a dummy callback if no better was specified by the driver.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Configuration
Update the ptp subsystem so that the ptp info->enable callback is always set; if a driver does not implement it, use a dummy callback instead to prevent NULL dereferences in the ioctl and sysfs handlers.
Linux kernel ptp subsystem info->enable callback = always set (use dummy callback when driver does not specify enable callback)
Event History
Frequently Asked Questions
What is the severity of CVE-2025-21814?
CVE-2025-21814 has a medium severity rating due to its potential to cause NULL pointer dereferences.
How do I fix CVE-2025-21814?
To fix CVE-2025-21814, update your Linux kernel to the latest version where this vulnerability has been patched.
What is affected by CVE-2025-21814?
CVE-2025-21814 affects the Linux kernel, specifically in drivers that do not implement the ->enable callback.
How can I determine if my system is vulnerable to CVE-2025-21814?
To determine if your system is vulnerable to CVE-2025-21814, check the version of your Linux kernel against the known affected versions.
Are there any workarounds for CVE-2025-21814?
Currently, the recommended action for CVE-2025-21814 is to apply the kernel update as there are no reliable workarounds available.