From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752229AbbFCAoa (ORCPT ); Tue, 2 Jun 2015 20:44:30 -0400 Received: from galahad.ideasonboard.com ([185.26.127.97]:49467 "EHLO galahad.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751398AbbFCAoX (ORCPT ); Tue, 2 Jun 2015 20:44:23 -0400 From: Laurent Pinchart To: Colin King Cc: Greg Kroah-Hartman , Felipe Balbi , Sudeep Holla , Valentin Rothberg , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH][V3] usb: isp1760: check for null return from kzalloc Date: Wed, 03 Jun 2015 03:43:23 +0300 Message-ID: <2210713.bNgAhNmNaU@avalon> User-Agent: KMail/4.14.3 (Linux/3.18.11-gentoo; KDE/4.14.3; x86_64; ; ) In-Reply-To: <1433268313-23423-1-git-send-email-colin.king@canonical.com> References: <1433268313-23423-1-git-send-email-colin.king@canonical.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Colin, Thank you for the patch. On Tuesday 02 June 2015 19:05:13 Colin King wrote: > From: Colin Ian King > > 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 Acked-by: Laurent Pinchart 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