Linux Kernel Refcount Leak Vulnerability in XFRM Policy Migration

A memory leak vulnerability has been identified in the Linux kernel's XFRM (IPsec) policy management. This issue arises from a double reference count increment in the policy migration function, which leads to an unreferenced object and a memory leak. The vulnerability affects the stable versions of the Linux kernel.

Impact

Exploitation of this vulnerability causes a memory leak, where allocated memory is not properly released, leading to increased memory usage and potential exhaustion of system resources.

Reproduction

The vulnerability can be reproduced by invoking the XFRM policy migration function, which will trigger the double reference count increment. This can be done using a tool like Syzkaller, which reported the issue.

Remediation

Users can upgrade to the latest stable version of the Linux kernel, where this vulnerability has been fixed.