linux-kernel - Re: [PATCH] watchdog: pcwd_usb: remove needless check before usb_free

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20200719140158.GA37652@roeck-us.net>
Date:   Sun, 19 Jul 2020 07:01:58 -0700
From:   Guenter Roeck <linux@...ck-us.net>
To:     Xu Wang <vulab@...as.ac.cn>
Cc:     wim@...ux-watchdog.org, linux-watchdog@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] watchdog: pcwd_usb: remove needless check before
 usb_free_coherent()

On Mon, Jul 13, 2020 at 05:53:48AM +0000, Xu Wang wrote:
> usb_free_coherent() is safe with NULL usb_pcwd->intr_buffer and 
> this check is not required.
> 
> Signed-off-by: Xu Wang <vulab@...as.ac.cn>

Reviewed-by: Guenter Roeck <linux@...ck-us.net>

> ---
>  drivers/watchdog/pcwd_usb.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/watchdog/pcwd_usb.c b/drivers/watchdog/pcwd_usb.c
> index 2f44af1831d0..6726301ac02e 100644
> --- a/drivers/watchdog/pcwd_usb.c
> +++ b/drivers/watchdog/pcwd_usb.c
> @@ -585,9 +585,8 @@ static struct notifier_block usb_pcwd_notifier = {
>  static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd)
>  {
>  	usb_free_urb(usb_pcwd->intr_urb);
> -	if (usb_pcwd->intr_buffer != NULL)
> -		usb_free_coherent(usb_pcwd->udev, usb_pcwd->intr_size,
> -				  usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
> +	usb_free_coherent(usb_pcwd->udev, usb_pcwd->intr_size,
> +			  usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
>  	kfree(usb_pcwd);
>  }
>