[patch] Input: egalax: potential NULL dereference on error

[Dan Carpenter <dan.carpenter@oracle.com>]

We didn't check input_allocate_device() for failures so it could lead to
a NULL deref.

Fixes: 6b0f8f9c52ef ('Input: add eGalaxTouch serial touchscreen driver')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/drivers/input/touchscreen/egalax_ts_serial.c b/drivers/input/touchscreen/egalax_ts_serial.c
index a078c1c..8becd26 100644
--- a/drivers/input/touchscreen/egalax_ts_serial.c
+++ b/drivers/input/touchscreen/egalax_ts_serial.c
@@ -104,10 +104,13 @@ static int egalax_connect(struct serio *serio, struct serio_driver *drv)
 	int error;
 
 	egalax = kzalloc(sizeof(struct egalax), GFP_KERNEL);
+	if (!egalax)
+		return -ENOMEM;
+
 	input_dev = input_allocate_device();
-	if (!egalax) {
+	if (!input_dev) {
 		error = -ENOMEM;
-		goto err_free_mem;
+		goto err_free_egalax;
 	}
 
 	egalax->serio = serio;
@@ -145,8 +148,8 @@ err_close_serio:
 	serio_close(serio);
 err_reset_drvdata:
 	serio_set_drvdata(serio, NULL);
-err_free_mem:
 	input_free_device(input_dev);
+err_free_egalax:
 	kfree(egalax);
 	return error;
 }