From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joe Perches <joe@perches.com>
Subject: Re: [RESEND][PATCH] scsi: esas2r: fix potential format string flaw
Date: Tue, 17 Dec 2013 21:42:50 -0800
Message-ID: <1387345370.13593.10.camel@joe-AO722>
References: <20131217182733.GA16202@www.outflux.net>
Mime-Version: 1.0
Content-Type: text/plain; charset="ISO-8859-1"
Content-Transfer-Encoding: 7bit
Return-path: <linux-scsi-owner@vger.kernel.org>
Received: from smtprelay0238.hostedemail.com ([216.40.44.238]:60605 "EHLO
	smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL)
	by vger.kernel.org with ESMTP id S1751241Ab3LRFmy (ORCPT
	<rfc822;linux-scsi@vger.kernel.org>);
	Wed, 18 Dec 2013 00:42:54 -0500
In-Reply-To: <20131217182733.GA16202@www.outflux.net>
Sender: linux-scsi-owner@vger.kernel.org
List-Id: linux-scsi@vger.kernel.org
To: Kees Cook <keescook@chromium.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, linux-kernel@vger.kernel.org, Bradley Grove <linuxdrivers@attotech.com>, "James E.J. Bottomley" <JBottomley@parallels.com>, linux-scsi@vger.kernel.org

On Tue, 2013-12-17 at 10:27 -0800, Kees Cook wrote:
> This makes sure format strings cannot leak into the printk call via the
> constructed buffer.
[]
> diff --git a/drivers/scsi/esas2r/esas2r_log.c b/drivers/scsi/esas2r/esas2r_log.c
[]
> @@ -171,7 +171,7 @@ static int esas2r_log_master(const long level,
>  		if (strlen(event_buffer) < buflen)
>  			strcat(buffer, "\n");
>  
> -		printk(event_buffer);
> +		printk("%s", event_buffer);

It's probably better to remove the

		if (strlen(event_buffer) < buflen)
			strcat(buffer, "\n");

and use

	printk("%s\n", event_buffer);

so that the output is always newline terminated.