[PATCH v2 0/2] gpiolib: don't allow user-space to crash the kernel with hot-unplugs

From: Bartosz Golaszewski
Date: Mon Nov 28 2022 - 13:08:27 EST


From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>

This is a second iteration of the changes that aim at fixing the situation
in which the user-space can provoke a NULL-pointer derefence in the kernel
when a GPIO device that's in use by user-space is removed.

v1 -> v2:
- add missing gdev->chip checks in patch 1/2
- add a second patch that protects the structures that can be accessed
by user-space calls against concurrent removal

Bartosz Golaszewski (2):
gpiolib: cdev: fix NULL-pointer dereferences
gpiolib: protect the GPIO device against being dropped while in use by
user-space

drivers/gpio/gpiolib-cdev.c | 240 +++++++++++++++++++++++++++++-------
drivers/gpio/gpiolib.c | 3 +
drivers/gpio/gpiolib.h | 5 +
3 files changed, 205 insertions(+), 43 deletions(-)

--
2.37.2