Linux Kernel GPIO Handling Vulnerability on Qualcomm Chipsets Causes Kernel Crashes

A vulnerability in the Linux kernel's IRQ chip handling for Qualcomm chipsets can lead to kernel crashes when managing non-wake capable GPIOs. The issue arises in the 'irqchip/qcom-mpm' driver, which currently lacks a necessary check for these GPIOs, causing crashes during interrupt setup. This vulnerability affects several versions of the Linux kernel on Qualcomm chipsets.

Impact

The vulnerability can cause kernel crashes, disrupting system operations and potentially leading to a denial of service.

Reproduction

The vulnerability can be reproduced by using the 'gpiomon' command to monitor a GPIO chip for non-wake GPIOs. The 'irq-qcom-mpm' driver will attempt to set up interrupts for these GPIOs, leading to a kernel paging request error and a crash. This can be observed on devices like the Qualcomm Robotics RB1.

Remediation

The vulnerability can be addressed by modifying the 'irqchip/qcom-mpm' driver to include the missing check for GPIO_NO_WAKE_IRQ, similar to the existing check in the 'qcom-pdc' driver.