A re‑entrancy bug in the Meson pinctrl driver for Amlogic A4 devices causes a deadlock when the pinconf‑pins sysfs node is read. The driver routine holds the device mutex while executing pinctrl_find_gpio_range_from_pin, which attempts to acquire the same mutex again, locking the kernel and stopping further kernel progress. The flaw is a concurrency bug (CWE-764) and results in a system‑wide denial of service once triggered.

All Linux kernel builds that include the Meson pinctrl driver for Amlogic A4 hardware are affected. No particular kernel version number is specified; any kernel containing the unpatched driver code referenced in the advisory is vulnerable. The issue is tied to the driver implementation rather than a specific patch level.

The advisory lists an EPSS score of less than 1%, indicating a low probability of real‑world exploitation. The flaw is not listed in the CISA KEV catalog. Exploitation would require a local actor to read the pinconf‑pins sysfs interface. While the precise permissions for that interface are not stated in the input, it is reasonable to infer that such access is typically restricted to privileged users; a non‑privileged user would normally be unable to trigger the deadlock. The potential impact is a system‑wide denial of service.