From mboxrd@z Thu Jan  1 00:00:00 1970
From: Olivier MATZ <olivier.matz@6wind.com>
Subject: Re: [PATCH] lib/cmdline: init parse result memeory
Date: Thu, 7 Dec 2017 15:48:03 +0100
Message-ID: <20171207144802.sgj33veeehxixhfk@glumotte.dev.6wind.com>
References: <20171115155402.9967-1-xuemingl@mellanox.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Cc: dev@dpdk.org
To: Xueming Li <xuemingl@mellanox.com>
Return-path: <dev-bounces@dpdk.org>
Received: from proxy.6wind.com (host.76.145.23.62.rev.coltfrance.com
 [62.23.145.76]) by dpdk.org (Postfix) with ESMTP id B02062B89
 for <dev@dpdk.org>; Thu,  7 Dec 2017 15:48:14 +0100 (CET)
Content-Disposition: inline
In-Reply-To: <20171115155402.9967-1-xuemingl@mellanox.com>
List-Id: DPDK patches and discussions <dev.dpdk.org>
List-Unsubscribe: <http://dpdk.org/ml/options/dev>,
 <mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://dpdk.org/ml/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <http://dpdk.org/ml/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
Errors-To: dev-bounces@dpdk.org
Sender: "dev" <dev-bounces@dpdk.org>

On Wed, Nov 15, 2017 at 11:54:02PM +0800, Xueming Li wrote:
> Initialize binary result memory before parsing to avoid garbage in
> parsing result.
> 
> Signed-off-by: Xueming Li <xuemingl@mellanox.com>
> ---
>  lib/librte_cmdline/cmdline_parse.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/lib/librte_cmdline/cmdline_parse.c b/lib/librte_cmdline/cmdline_parse.c
> index 3e12ee54f..9124758f1 100644
> --- a/lib/librte_cmdline/cmdline_parse.c
> +++ b/lib/librte_cmdline/cmdline_parse.c
> @@ -267,6 +267,8 @@ cmdline_parse(struct cmdline *cl, const char * buf)
>  	if (!cl || !buf)
>  		return CMDLINE_PARSE_BAD_ARGS;
>  
> +	memset(tmp_result.buf, 0, sizeof(tmp_result.buf));
> +
>  	ctx = cl->ctx;
>  
>  	/*


Did you see an issue (a bug or a crash) without the memset()?
Or is it to avoid filling unused fields in the parsed struct?

I'm not sure if your patch is enough: cmdline_parse() calls match_inst()
for each registered command. If a command partially matches (only the
first tokens), the buffer is modified. So the next one will start
with a dirty buffer.

I suggest to put the memset() in match_inst() instead. Something
like this:

	if (resbuf != NULL)
		memset(resbuf, 0, resbuf_size);


It will reset the buffer before using it.

Olivier