Input: evdev - call input_flush_device() on release(), not flush() (09264098) · Commits · 戴 / test

input_flush_device() should only be called once the struct file is being released and no open descriptors remain, but evdev_flush() was calling it whenever a file descriptor was closed. This caused uploaded force-feedback effects to be erased when a process did a dup()/close() on the event FD, called system(), etc. Call input_flush_device() from evdev_release() instead. Reported-by:

Mathieu Maret <mathieu.maret@gmail.com> Signed-off-by:

Brendan Shanks <bshanks@codeweavers.com> Link: https://lore.kernel.org/r/20200421231003.7935-1-bshanks@codeweavers.com Cc: stable@vger.kernel.org Signed-off-by:

Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/evdev.c

+4 −15

Original line number	Diff line number	Diff line
		@@ -326,20 +326,6 @@ static int evdev_fasync(int fd, struct file *file, int on)
		return fasync_helper(fd, file, on, &client->fasync);
		}

		static int evdev_flush(struct file *file, fl_owner_t id)
		{
		struct evdev_client *client = file->private_data;
		struct evdev *evdev = client->evdev;

		mutex_lock(&evdev->mutex);

		if (evdev->exist && !client->revoked)
		input_flush_device(&evdev->handle, file);

		mutex_unlock(&evdev->mutex);
		return 0;
		}

		static void evdev_free(struct device *dev)
		{
		struct evdev *evdev = container_of(dev, struct evdev, dev);
		@@ -453,6 +439,10 @@ static int evdev_release(struct inode inode, struct file file)
		unsigned int i;

		mutex_lock(&evdev->mutex);

		if (evdev->exist && !client->revoked)
		input_flush_device(&evdev->handle, file);

		evdev_ungrab(evdev, client);
		mutex_unlock(&evdev->mutex);

		@@ -1310,7 +1300,6 @@ static const struct file_operations evdev_fops = {
		.compat_ioctl = evdev_ioctl_compat,
		#endif
		.fasync = evdev_fasync,
		.flush = evdev_flush,
		.llseek = no_llseek,
		};

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