Input: fix defuzzing logic

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.

Cc: stable@vger.kernel.org
Reviewed-by: Andrew de los Reyes <adlr@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/drivers/input/input.c b/drivers/input/input.c
index 1c4c0db05550..29ca0bb4f561 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -257,9 +257,10 @@ 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);