From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas.monjalon-pdR9zngts4EAvxtiuMwx3w@public.gmane.org>
Subject: Re: [PATCH v1] afpacket: fix critical issue reported by
	klocwork
Date: Wed, 25 Feb 2015 10:56:22 +0100
Message-ID: <1918339.MLD1NqnMmG@xps13>
References: <1423732089-6202-1-git-send-email-cunming.liang@intel.com>
 <1514821.oaVEE2NRMm@xps13>
 <D0158A423229094DA7ABF71CF2FA0DA3118DED48@shsmsx102.ccr.corp.intel.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7Bit
Cc: dev-VfR2kkLFssw@public.gmane.org, John Linville <linville-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
To: "Liang, Cunming" <cunming.liang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Return-path: <dev-bounces-VfR2kkLFssw@public.gmane.org>
In-Reply-To: <D0158A423229094DA7ABF71CF2FA0DA3118DED48-E2R4CRU6q/6iAffOGbnezLfspsVTdybXVpNB7YpNyf8@public.gmane.org>
List-Id: patches and discussions about DPDK <dev.dpdk.org>
List-Unsubscribe: <http://dpdk.org/ml/options/dev>,
 <mailto:dev-request-VfR2kkLFssw@public.gmane.org?subject=unsubscribe>
List-Archive: <http://dpdk.org/ml/archives/dev/>
List-Post: <mailto:dev-VfR2kkLFssw@public.gmane.org>
List-Help: <mailto:dev-request-VfR2kkLFssw@public.gmane.org?subject=help>
List-Subscribe: <http://dpdk.org/ml/listinfo/dev>,
 <mailto:dev-request-VfR2kkLFssw@public.gmane.org?subject=subscribe>
Errors-To: dev-bounces-VfR2kkLFssw@public.gmane.org
Sender: "dev" <dev-bounces-VfR2kkLFssw@public.gmane.org>

2015-02-25 09:52, Liang, Cunming:
> From: Thomas Monjalon [mailto:thomas.monjalon-pdR9zngts4EAvxtiuMwx3w@public.gmane.org]
> > 2015-02-25 00:57, Liang, Cunming:
> > > From: John W. Linville [mailto:linville-2XuSBdqkA4R54TAoqtyWWQ@public.gmane.org]
> > > > On Fri, Feb 20, 2015 at 11:19:59AM +0100, Thomas Monjalon wrote:
> > > > > 2015-02-12 17:08, Cunming Liang:
> > > > > > --- a/lib/librte_pmd_af_packet/rte_eth_af_packet.c
> > > > > > +++ b/lib/librte_pmd_af_packet/rte_eth_af_packet.c
> > > > > > @@ -439,13 +439,15 @@ rte_pmd_init_internals(const char *name,
> > > > > >  	size_t ifnamelen;
> > > > > >  	unsigned k_idx;
> > > > > >  	struct sockaddr_ll sockaddr;
> > > > > > -	struct tpacket_req *req;
> > > > > > +	struct tpacket_req *req = NULL;
> > > > >
> > > > > If *internals is set to NULL, there should be no case where req used
> > > > > and undefined.
> > >
> > > [LCM] Agree, so that's why I add '*internals = NULL' below as well.
> > > >
> > > > I agree -- it looks to me like req is protected by checking for
> > > > *internals == NULL.  I don't think this patch is necessary.
> > >
> > > [LCM] The major piece of the patch is add setting for '*internals=NULL;'.
> > 
> > Yes understood, but it is already initialized to NULL before calling
> > rte_pmd_init_internals():
> > http://dpdk.org/browse/dpdk/tree/lib/librte_pmd_af_packet/rte_eth_af_packet
> > .c#n706
> [LCM] I see, it's complained by klocwork.
> So either adding 'internals=NULL' or adding some comments helps to avoid checking again on the next scanning.
> How do you think ?

No, we don't have to pollute the code for a tool.
You should check how to disable this false positive in your tool.