This series transitions the UAF prevention logic within the GPIO core (gpiolib) to use the 'revocable' mechanism.
The existing code aims to prevent UAF issues when the underlying GPIO chip is removed. This series replaces that custom logic with the generic 'revocable' API, which is designed to handle such lifecycle dependencies. There should be no changes in behavior. The series applies after: - https://lore.kernel.org/all/[email protected] - https://lore.kernel.org/all/[email protected] Bartosz: the series was planned to send after -rc1 comes. But I think it'd be great to send out for your early review and testing if possible. The series base on v6.19-rc8, driver-core-next, and gpio/for-next. Please use the temporary integration testing branch https://git.kernel.org/pub/scm/linux/kernel/git/tzungbi/chrome-platform.git/log/?h=gpio_rev if you'd like to. Tzung-Bi Shih (11): gpio: Access `gpio_bus_type` in gpiochip_setup_dev() gpio: Remove redundant check for struct gpio_chip gpio: sysfs: Remove redundant check for struct gpio_chip gpio: Ensure struct gpio_chip for gpiochip_setup_dev() gpio: cdev: Don't check struct gpio_chip in gpio_chrdev_open() => The first 5 patches are refactors. They try to make the subsequent changes easier or at least clear. selftests: gpio: Add gpio-cdev-uaf tests => The following patch adds kselftest cases for some classic UAF scenarios. gpio: Add revocable provider handle for struct gpio_chip gpio: cdev: Leverage revocable for accessing struct gpio_chip gpio: Remove gpio_chip_guard by using revocable gpio: Leverage revocable for accessing struct gpio_chip => The following 4 patches start to replace the existing code. gpio: Remove unused `chip` and `srcu` in struct gpio_device => The last patch removes the unused fields for the custom logic as all of them should be transiting to revocable. --- v2: - Separate fixes patches from v1. Some of them have been landed. - Combine small patches into one as they become simpler after applying https://lore.kernel.org/all/[email protected]. v1: https://lore.kernel.org/all/[email protected] drivers/gpio/gpiolib-cdev.c | 97 +++--- drivers/gpio/gpiolib-cdev.h | 3 +- drivers/gpio/gpiolib-sysfs.c | 50 ++- drivers/gpio/gpiolib-sysfs.h | 11 +- drivers/gpio/gpiolib.c | 303 +++++++++--------- drivers/gpio/gpiolib.h | 27 +- tools/testing/selftests/gpio/Makefile | 5 +- tools/testing/selftests/gpio/gpio-cdev-uaf.c | 292 +++++++++++++++++ tools/testing/selftests/gpio/gpio-cdev-uaf.sh | 63 ++++ 9 files changed, 575 insertions(+), 276 deletions(-) create mode 100644 tools/testing/selftests/gpio/gpio-cdev-uaf.c create mode 100755 tools/testing/selftests/gpio/gpio-cdev-uaf.sh -- 2.53.0.rc2.204.g2597b5adb4-goog
