Linux Kernel K3 SOC Information Regmap Leak Vulnerability

A vulnerability exists in the Linux kernel's K3 SOC information driver, where the MMIO regmap allocated during the probe process is not properly freed. This can lead to a resource leak, as the allocated regmap remains in memory and is not released back to the system. The issue arises because the driver does not use the device-managed allocator, which would automatically free the regmap on probe failures or when the driver is unbound. The vulnerability affects several versions of the Linux kernel.

Impact

The vulnerability can cause a memory leak by failing to release allocated resources, which can lead to increased memory usage and potential exhaustion of available memory resources.

Reproduction

The vulnerability can be reproduced by loading the K3 SOC information driver in a version of the Linux kernel that is affected by this issue. During the probe process, the driver allocates a regmap for memory-mapped I/O, but if the probe fails or the driver is unbound, the regmap is not freed, leading to a resource leak.

Remediation

The vulnerability has been addressed by modifying the driver to use the device-managed regmap allocator, which automatically frees the regmap on probe failures and when the driver is unbound. Users can apply the latest patches available in the Linux kernel stable tree to mitigate this issue.