On Fri, Apr 06, 2018 at 11:12:42AM -0700, Dmitry Torokhov wrote:
> UI_SET_LEDBIT ioctl() causes the following KASAN splat when used with
> led > LED_CHARGING:
>
> [ 1274.663418] BUG: KASAN: slab-out-of-bounds in
> input_leds_connect+0x611/0x730 [input_leds]
> [ 1274.663426] Write of size 8 at addr ffff88003377b2c0 by task
> ckb-next-daemon/5128
>
> This happens because we were writing to the led structure before making
> sure that it exists.
>
> Reported-by: Tasos Sahanidis <ta...@tasossah.com>
> Tested-by: Tasos Sahanidis <ta...@tasossah.com>
> Cc: sta...@vger.kernel.org
> Signed-off-by: Dmitry Torokhov <dmitry.torok...@gmail.com>
Reviewed-by: Peter Hutterer <peter.hutte...@who-t.net>
Cheers,
Peter
> ---
> drivers/input/input-leds.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/input/input-leds.c b/drivers/input/input-leds.c
> index 766bf26601163..5f04b2d946350 100644
> --- a/drivers/input/input-leds.c
> +++ b/drivers/input/input-leds.c
> @@ -88,6 +88,7 @@ static int input_leds_connect(struct input_handler *handler,
> const struct input_device_id *id)
> {
> struct input_leds *leds;
> + struct input_led *led;
> unsigned int num_leds;
> unsigned int led_code;
> int led_no;
> @@ -119,14 +120,13 @@ static int input_leds_connect(struct input_handler
> *handler,
>
> led_no = 0;
> for_each_set_bit(led_code, dev->ledbit, LED_CNT) {
> - struct input_led *led = &leds->leds[led_no];
> + if (!input_led_info[led_code].name)
> + continue;
>
> + led = &leds->leds[led_no];
> led->handle = &leds->handle;
> led->code = led_code;
>
> - if (!input_led_info[led_code].name)
> - continue;
> -
> led->cdev.name = kasprintf(GFP_KERNEL, "%s::%s",
> dev_name(&dev->dev),
> input_led_info[led_code].name);
> --
> 2.17.0.484.g0c8726318c-goog
