Linux Kernel Memory Leak Vulnerability in VMWGFX DRM Component

A memory leak vulnerability has been identified in the Linux kernel's VMWGFX Direct Rendering Manager (DRM) component. This issue arises in the 'vmw_mksstat_add_ioctl' function, where a failure to copy a description string from userspace results in the instance descriptor's memory not being freed. Consequently, this oversight leads to a memory leak. The vulnerability affects several versions of the Linux kernel.

Impact

Exploitation of this vulnerability causes a memory leak, where allocated memory is not properly released, potentially leading to increased memory usage and degradation of system performance over time.

Reproduction

To reproduce this vulnerability, invoke the 'vmw_mksstat_add_ioctl' function in the VMWGFX DRM component with a description string that causes the copy operation to fail. This will trigger the error handling path, where the function returns an '-EFAULT' error without freeing the allocated memory, thus creating a memory leak.

Remediation

Users can upgrade to the latest version of the Linux kernel, where this vulnerability has been addressed. The specific commit that resolves this issue is '53066b144715332ce9370143c33c50d9a4d3e809', which is available in the Linux kernel stable tree.