From b40769ee2ed09ed6c6da33b0cbdf423ff94f685b Mon Sep 17 00:00:00 2001
From: Sean Young <sean@mess.org>
Date: Sat, 26 Nov 2016 19:31:24 -0200
Subject: [PATCH] [media] lirc: fix error paths in lirc_cdev_add()
"c77d17c0 [media] lirc: use-after free" introduces two problems:
cdev_del() can be called with a NULL argument, and the kobject_put()
path will cause a double free.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
---
drivers/media/rc/lirc_dev.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/drivers/media/rc/lirc_dev.c b/drivers/media/rc/lirc_dev.c
index d3039efb4e7cf..3854809e85311 100644
--- a/drivers/media/rc/lirc_dev.c
+++ b/drivers/media/rc/lirc_dev.c
@@ -157,13 +157,13 @@ static const struct file_operations lirc_dev_fops = {
static int lirc_cdev_add(struct irctl *ir)
{
- int retval = -ENOMEM;
struct lirc_driver *d = &ir->d;
struct cdev *cdev;
+ int retval;
cdev = cdev_alloc();
if (!cdev)
- goto err_out;
+ return -ENOMEM;
if (d->fops) {
cdev->ops = d->fops;
@@ -177,10 +177,8 @@ static int lirc_cdev_add(struct irctl *ir)
goto err_out;
retval = cdev_add(cdev, MKDEV(MAJOR(lirc_base_dev), d->minor), 1);
- if (retval) {
- kobject_put(&cdev->kobj);
+ if (retval)
goto err_out;
- }
ir->cdev = cdev;