diff options
author | Johan Hovold <johan@kernel.org> | 2021-03-01 10:05:18 +0100 |
---|---|---|
committer | Bartosz Golaszewski <bgolaszewski@baylibre.com> | 2021-03-08 11:59:17 +0100 |
commit | a6112998ee45514def58200a7914706c0703f3d7 (patch) | |
tree | 38fa3e70278fe1c3624f6fd90240f78355de72ad | |
parent | 542104ee0cafe789cc07291b71818c143df8d623 (diff) | |
download | linux-a6112998ee45514def58200a7914706c0703f3d7.tar.bz2 |
gpio: fix NULL-deref-on-deregistration regression
Fix a NULL-pointer deference when deregistering the gpio character
device that was introduced by the recent stub-driver hack. When the new
"driver" is unbound as part of deregistration, driver core clears the
driver-data pointer which is used to retrieve the struct gpio_device in
its release callback.
Fix this by using container_of() in the release callback as should have
been done all along.
Fixes: 4731210c09f5 ("gpiolib: Bind gpio_device to a driver to enable fw_devlink=on by default")
Cc: Saravana Kannan <saravanak@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reported-by: syzbot+d27b4c8adbbff70fbfde@syzkaller.appspotmail.com
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
-rw-r--r-- | drivers/gpio/gpiolib.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index adf55db080d8..6e0572515d02 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -474,7 +474,7 @@ EXPORT_SYMBOL_GPL(gpiochip_line_is_valid); static void gpiodevice_release(struct device *dev) { - struct gpio_device *gdev = dev_get_drvdata(dev); + struct gpio_device *gdev = container_of(dev, struct gpio_device, dev); list_del(&gdev->list); ida_free(&gpio_ida, gdev->id); @@ -605,7 +605,6 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, goto err_free_ida; device_initialize(&gdev->dev); - dev_set_drvdata(&gdev->dev, gdev); if (gc->parent && gc->parent->driver) gdev->owner = gc->parent->driver->owner; else if (gc->owner) |