Linux Kernel hwmon: xgene Ioremap and Memremap Leak Vulnerability

A resource leak vulnerability has been identified in the Linux kernel's hwmon subsystem for the xgene platform. The issue arises in the 'xgene_hwmon_probe' function, where memory mapped by 'ioremap' and 'memremap' is not properly released. This oversight can lead to a memory leak. The vulnerability affects several versions of the Linux kernel.

Impact

The vulnerability can cause a memory leak, potentially leading to increased memory usage and degradation of system performance over time.

Reproduction

The vulnerability can be reproduced by loading the xgene hwmon driver, which will trigger the 'xgene_hwmon_probe' function. The function will map shared memory using 'ioremap' or 'memremap', depending on the version. However, the mapped memory will not be released, causing a leak.

Remediation

The vulnerability has been addressed by modifying the 'ioremap' and 'memremap' calls to use their managed counterparts, 'devm_ioremap' and 'devm_memremap', which automatically handle memory release.