pinctrl: mediatek: paris: bypass pinctrl GPIO layer in set GPIO direction
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.6.160, 6.12.114, 6.18.53
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: pinctrl: mediatek: paris: bypass pinctrl GPIO layer in set GPIO direction pinctrl_gpio_direction_input() / pinctrl_gpio_direction_output() take the pinctrl mutex. This causes a gpiochip operations to need to sleep. Worse yet, the .can_sleep field in the gpiochip is not set. This causes the shared GPIO proxy to trip over, as it uses gpiod_cansleep() to check whether it can use a spinlock or needs a mutex. In this case, it ends up taking a spinlock, then calls pinctrl_gpio_direction_output(), which takes a mutex. This causes a huge warning. While this class of Mediatek hardware does not have separate clear/set registers, the pinctrl context has a spinlock that is taken whenever a register read-modify-write is done. Also, once the GPIO function is selected / muxed in, further GPIO operations do not involve pinctrl operations or state. The GPIO direction and level values do not require toggling the pinmux or any other pin config options. Switch to directly calling mtk_pinmux_gpio_set_direction() in the GPIO set direction callbacks to avoid taking the pinctrl mutex. Drop the .gpio_set_direction field in mtk_pmxops to signal we are no longer using the pinctrl GPIO layer for setting the direction.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 805250982bb5c5ce4a6e52e1d87204c5feea0dd1 · fixed in 482ba972f9638f467df2d498b46384a1d1f80529; From 805250982bb5c5ce4a6e52e1d87204c5feea0dd1 · fixed in 3c4897861759fd8bd81dc2ada92121ac76332592; From 805250982bb5c5ce4a6e52e1d87204c5feea0dd1 · fixed in 428b031dad390edd5da729b9afd474a95dc4f76b; From 805250982bb5c5ce4a6e52e1d87204c5feea0dd1 · fixed in c87c9046c4e00d599454e033a477176c4d73ac2a
- Linux Linux
4.20
- KernelLinux
From 4.20.0 · fixed in 6.6.160; From 6.7.0 · fixed in 6.12.114; From 6.13.0 · fixed in 6.18.53