From: Heiko Stuebner <heiko@sntech.de>
Date: Wed, 1 Feb 2012 18:33:01 +0000 (-0800)
Subject: Input: evdev - fix variable initialisation
X-Git-Tag: firefly_0821_release~7613^2~180
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=1f8c5cecfe44994cd617ba2803f41fb56d53e91c;p=firefly-linux-kernel-4.4.55.git

Input: evdev - fix variable initialisation

Commit 509f87c5f564 (evdev - do not block waiting for an event if
fd
is nonblock) created a code path were it was possible to use retval
uninitialized.

This could lead to the xorg evdev input driver getting corrupt data
and refusing to work with log messages like
	AUO-Pixcir touchscreen: Read error: Success
	sg060_keys: Read error: Success
	AUO-Pixcir touchscreen: Read error: Success
	sg060_keys: Read error: Success
(for drivers auo-pixcir-ts and gpio-keys).

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
---

diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index d497c972e714..6288d7d84fa7 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -404,7 +404,7 @@ static ssize_t evdev_read(struct file *file, char __user *buffer,
 	struct evdev_client *client = file->private_data;
 	struct evdev *evdev = client->evdev;
 	struct input_event event;
-	int retval;
+	int retval = 0;
 
 	if (count < input_event_size())
 		return -EINVAL;