From 92a3a58788790645c6143b5353ef065fd26110bb Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Tue, 5 Jan 2010 17:56:01 -0800 Subject: [PATCH] Input: cleanse capabilities bits before registering device To avoid showing garbage in capability bits, zero out bitmasks absent from dev->evbit in case driver inadvertently leaves some garbage there. Signed-off-by: Dmitry Torokhov --- drivers/input/input.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/drivers/input/input.c b/drivers/input/input.c index 910d7be06eff..a31394c1eca8 100644 --- a/drivers/input/input.c +++ b/drivers/input/input.c @@ -1497,6 +1497,25 @@ void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int } EXPORT_SYMBOL(input_set_capability); +#define INPUT_CLEANSE_BITMASK(dev, type, bits) \ + do { \ + if (!test_bit(EV_##type, dev->evbit)) \ + memset(dev->bits##bit, 0, \ + sizeof(dev->bits##bit)); \ + } while (0) + +static void input_cleanse_bitmasks(struct input_dev *dev) +{ + INPUT_CLEANSE_BITMASK(dev, KEY, key); + INPUT_CLEANSE_BITMASK(dev, REL, rel); + INPUT_CLEANSE_BITMASK(dev, ABS, abs); + INPUT_CLEANSE_BITMASK(dev, MSC, msc); + INPUT_CLEANSE_BITMASK(dev, LED, led); + INPUT_CLEANSE_BITMASK(dev, SND, snd); + INPUT_CLEANSE_BITMASK(dev, FF, ff); + INPUT_CLEANSE_BITMASK(dev, SW, sw); +} + /** * input_register_device - register device with input core * @dev: device to be registered @@ -1522,6 +1541,9 @@ int input_register_device(struct input_dev *dev) /* KEY_RESERVED is not supposed to be transmitted to userspace. */ __clear_bit(KEY_RESERVED, dev->keybit); + /* Make sure that bitmasks not mentioned in dev->evbit are clean. */ + input_cleanse_bitmasks(dev); + /* * If delay and period are pre-set by the driver, then autorepeating * is handled by the driver itself and we don't do it in input.c. -- GitLab