Input: fix defuzzing logic

commit 50c5d36dab930b1f1b1e3348b8608aa8b9ee7610 upstream.

We attempt to remove noise from coordinates reported by devices in
input_handle_abs_event(), unfortunately, unless we were dropping the
event altogether, we were ignoring the adjusted value and were passing
on the original value instead.

Reviewed-by: Andrew de los Reyes <[email protected]>
Reviewed-by: Benson Leung <[email protected]>
Reviewed-by: David Herrmann <[email protected]>
Reviewed-by: Henrik Rydberg <[email protected]>
Signed-off-by: Dmitry Torokhov <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: franciscofranco <[email protected]>

drivers/input/input.c

@@ -256,9 +256,10 @@ static int input_handle_abs_event(struct input_dev *dev,
 }
 
 static int input_get_disposition(struct input_dev *dev,
-			  unsigned int type, unsigned int code, int value)
+			  unsigned int type, unsigned int code, int *pval)
 {
 	int disposition = INPUT_IGNORE_EVENT;
+	int value = *pval;
 
 	switch (type) {
 
@@ -357,6 +358,7 @@ static int input_get_disposition(struct input_dev *dev,
 		break;
 	}
 
+	*pval = value;
 	return disposition;
 }
 
@@ -365,7 +367,7 @@ static void input_handle_event(struct input_dev *dev,
 {
 	int disposition;
 
-	disposition = input_get_disposition(dev, type, code, value);
+	disposition = input_get_disposition(dev, type, code, &value);
 
 	if ((disposition & INPUT_PASS_TO_DEVICE) && dev->event)
 		dev->event(dev, type, code, value);