Input: uinput - support injecting multiple events in one write() call
Rework the code in uinput_inject_event so that it matches the code in
evdev_write and allows injecting more than one event, or zero events.
Signed-off-by: Ryan Mallon <rmallon@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c
index a0a4bba..7728359 100644
--- a/drivers/input/misc/uinput.c
+++ b/drivers/input/misc/uinput.c
@@ -430,20 +430,30 @@
return retval;
}
-static ssize_t uinput_inject_event(struct uinput_device *udev,
- const char __user *buffer, size_t count)
+static ssize_t uinput_inject_events(struct uinput_device *udev,
+ const char __user *buffer, size_t count)
{
struct input_event ev;
+ size_t bytes = 0;
- if (count < input_event_size())
+ if (count != 0 && count < input_event_size())
return -EINVAL;
- if (input_event_from_user(buffer, &ev))
- return -EFAULT;
+ while (bytes + input_event_size() <= count) {
+ /*
+ * Note that even if some events were fetched successfully
+ * we are still going to return EFAULT instead of partial
+ * count to let userspace know that it got it's buffers
+ * all wrong.
+ */
+ if (input_event_from_user(buffer + bytes, &ev))
+ return -EFAULT;
- input_event(udev->dev, ev.type, ev.code, ev.value);
+ input_event(udev->dev, ev.type, ev.code, ev.value);
+ bytes += input_event_size();
+ }
- return input_event_size();
+ return bytes;
}
static ssize_t uinput_write(struct file *file, const char __user *buffer,
@@ -460,7 +470,7 @@
return retval;
retval = udev->state == UIST_CREATED ?
- uinput_inject_event(udev, buffer, count) :
+ uinput_inject_events(udev, buffer, count) :
uinput_setup_device(udev, buffer, count);
mutex_unlock(&udev->mutex);