Overview
In the Linux kernel, the following vulnerability has been resolved:
pinctrl: qcom: msm: mark certain pins as invalid for interrupts
On some platforms, the UFS-reset pin has no interrupt logic in TLMM but
is nevertheless registered as a GPIO in the kernel. This enables the
user-space to trigger a BUG() in the pinctrl-msm driver by running, for
example: `gpiomon -c 0 113` on RB2.
The exact culprit is requesting pins whose intr_detection_width setting
is not 1 or 2 for interrupts. This hits a BUG() in
msm_gpio_irq_set_type(). Potentially crashing the kernel due to an
invalid request from user-space is not optimal, so let's go through the
pins and mark those that would fail the check as invalid for the irq chip
as we should not even register them as available irqs.
This function can be extended if we determine that there are more
corner-cases like this.