From mboxrd@z Thu Jan 1 00:00:00 1970 From: Logan Gunthorpe Subject: [PATCH v2 13/16] rapidio: utilize new cdev_device_add helper function Date: Sat, 25 Feb 2017 23:38:14 -0700 Message-ID: <1488091097-12328-14-git-send-email-logang@deltatee.com> References: <1488091097-12328-1-git-send-email-logang@deltatee.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: linux-scsi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, rtc-linux-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org, linux-gpio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-iio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-pci-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-nvdimm-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mtd-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-input-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-media-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Greg Kroah-Hartman , Dan Williams , Alexander Viro , Johannes Thumshirn , Jan Kara , Arnd Bergmann , Sajjan Vikas C , Dmitry Torokhov , Linus Walleij , Alexandre Courbot , Peter Huewe , Marcel Selhorst , Jarkko Sakkinen , Jason Gunthorpe , Olof Johansson , Doug Ledford , Sean Hefty , Hal Rosenstock , Dmitry Vyukov , Haggai Eran , Parav Pandit , Leon Romanovsky , Hartmut Knaack In-Reply-To: <1488091097-12328-1-git-send-email-logang-OTvnGxWRz7hWk0Htik3J/w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-nvdimm-bounces-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org Sender: "Linux-nvdimm" List-Id: linux-fsdevel.vger.kernel.org This driver did not originally set kobj.parent so it likely had potential a use after free bug which this patch fixes. We convert from device_register to device_initialize/cdev_device_add. While we are at it we use put_device instead of kfree (as recommended by the device_initialize documentation). We also remove an unnecessary extra get_device from the code. Signed-off-by: Logan Gunthorpe --- drivers/rapidio/devices/rio_mport_cdev.c | 24 ++++++++---------------- 1 file changed, 8 insertions(+), 16 deletions(-) diff --git a/drivers/rapidio/devices/rio_mport_cdev.c b/drivers/rapidio/devices/rio_mport_cdev.c index 9013a58..b8165e9 100644 --- a/drivers/rapidio/devices/rio_mport_cdev.c +++ b/drivers/rapidio/devices/rio_mport_cdev.c @@ -2445,31 +2445,25 @@ static struct mport_dev *mport_cdev_add(struct rio_mport *mport) mutex_init(&md->buf_mutex); mutex_init(&md->file_mutex); INIT_LIST_HEAD(&md->file_list); - cdev_init(&md->cdev, &mport_fops); - md->cdev.owner = THIS_MODULE; - ret = cdev_add(&md->cdev, MKDEV(MAJOR(dev_number), mport->id), 1); - if (ret < 0) { - kfree(md); - rmcd_error("Unable to register a device, err=%d", ret); - return NULL; - } - md->dev.devt = md->cdev.dev; + device_initialize(&md->dev); + md->dev.devt = MKDEV(MAJOR(dev_number), mport->id); md->dev.class = dev_class; md->dev.parent = &mport->dev; md->dev.release = mport_device_release; dev_set_name(&md->dev, DEV_NAME "%d", mport->id); atomic_set(&md->active, 1); - ret = device_register(&md->dev); + cdev_init(&md->cdev, &mport_fops); + md->cdev.owner = THIS_MODULE; + + ret = cdev_device_add(&md->cdev, &md->dev); if (ret) { rmcd_error("Failed to register mport %d (err=%d)", mport->id, ret); goto err_cdev; } - get_device(&md->dev); - INIT_LIST_HEAD(&md->doorbells); spin_lock_init(&md->db_lock); INIT_LIST_HEAD(&md->portwrites); @@ -2514,8 +2508,7 @@ static struct mport_dev *mport_cdev_add(struct rio_mport *mport) return md; err_cdev: - cdev_del(&md->cdev); - kfree(md); + put_device(&md->dev); return NULL; } @@ -2579,7 +2572,7 @@ static void mport_cdev_remove(struct mport_dev *md) atomic_set(&md->active, 0); mport_cdev_terminate_dma(md); rio_del_mport_pw_handler(md->mport, md, rio_mport_pw_handler); - cdev_del(&(md->cdev)); + cdev_device_del(&md->cdev, &md->dev); mport_cdev_kill_fasync(md); flush_workqueue(dma_wq); @@ -2604,7 +2597,6 @@ static void mport_cdev_remove(struct mport_dev *md) rio_release_inb_dbell(md->mport, 0, 0x0fff); - device_unregister(&md->dev); put_device(&md->dev); } -- 2.1.4