Re: [PATCH][V3] usb: isp1760: check for null return from kzalloc

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Colin,

Thank you for the patch.

On Tuesday 02 June 2015 19:05:13 Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
> 
> isp1760_ep_alloc_request allocates a structure with kzalloc without checking
> for NULL and then returns a pointer to one of the structure fields. As the
> field happens to be the first in the structure the caller can properly
> check for NULL, but this is risky if the structure layout is changed later.
> Add an explicit NULL check for the kzalloc return value
> 
> Detected with smatch static analysis:
> 
> drivers/usb/isp1760/isp1760-udc.c:816 isp1760_ep_alloc_request()
>   error: potential null dereference 'req'.  (kzalloc returns null)
> 
> [ thanks to Laurent Pinchart for improved commit message ]
> 
> Signed-off-by: Colin Ian King <colin.king@canonical.com>

Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Felipe, I expect you to pick this up, please let me know if there's any issue.

> ---
>  drivers/usb/isp1760/isp1760-udc.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/usb/isp1760/isp1760-udc.c
> b/drivers/usb/isp1760/isp1760-udc.c index 3fc4fe7..18ebf5b 100644
> --- a/drivers/usb/isp1760/isp1760-udc.c
> +++ b/drivers/usb/isp1760/isp1760-udc.c
> @@ -812,6 +812,8 @@ static struct usb_request
> *isp1760_ep_alloc_request(struct usb_ep *ep, struct isp1760_request *req;
> 
>  	req = kzalloc(sizeof(*req), gfp_flags);
> +	if (!req)
> +		return NULL;
> 
>  	return &req->req;
>  }

-- 
Regards,

Laurent Pinchart