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 <dtor@mail.ru>
diff --git a/drivers/input/input.c b/drivers/input/input.c
index 910d7be..a31394c 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -1497,6 +1497,25 @@
}
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 @@
/* 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.
