From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1751567AbeEDQIk (ORCPT <rfc822;w@1wt.eu>);
        Fri, 4 May 2018 12:08:40 -0400
Received: from mx2.suse.de ([195.135.220.15]:50571 "EHLO mx2.suse.de"
        rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
        id S1751196AbeEDQIj (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
        Fri, 4 May 2018 12:08:39 -0400
Date: Fri, 4 May 2018 18:08:37 +0200
From: Michal =?UTF-8?B?U3VjaMOhbmVr?= <msuchanek@suse.de>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>,
        Ingo Molnar <mingo@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Kees Cook <keescook@chromium.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Laura Abbott <lauraa@codeaurora.org>,
        Gargi Sharma <gs051095@gmail.com>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        Viresh Kumar <viresh.kumar@linaro.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] init/main.c: simplify repair_env_string
Message-ID: <20180504180837.346cd966@kitsune.suse.cz>
In-Reply-To: <20180504114035.111ad8f7@gandalf.local.home>
References: <151075904367.14434.5164139208561977016.stgit@hbathini.in.ibm.com>
        <20171215213317.3151-1-msuchanek@suse.de>
        <20180504114035.111ad8f7@gandalf.local.home>
Organization: SUSE Linux
X-Mailer: Claws Mail 3.15.1-dirty (GTK+ 2.24.31; x86_64-suse-linux-gnu)
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Fri, 4 May 2018 11:40:35 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> Cleaning out my INBOX, I stumbled across this old patch.
> 
> On Fri, 15 Dec 2017 22:33:17 +0100
> Michal Suchanek <msuchanek@suse.de> wrote:
> 
> > Quoting characters are now removed from the parameter so value
> > always follows directly after the NUL terminating parameter name.
> > 
> > Signed-off-by: Michal Suchanek <msuchanek@suse.de>
> > ---
> >  init/main.c | 13 ++++---------
> >  1 file changed, 4 insertions(+), 9 deletions(-)
> > 
> > Since the previous "[PATCH v9 3/8] lib/cmdline.c: add backslash
> > support to kernel commandline parsing" adds the memmove in
> > lib/cmdline.c it is now superfluous in init/main.c  
> 
> I don't believe the above patches were ever applied. Were they?

No, they weren't.

The reason to write them was to support the fadump_extra_args argument
with peculiar semantics that required the quoting cleanup in kernel
argument parsing.

A different solution for the fadump memory consumption is in the works
so I dropped this. There was lack of interest from reviewers, too.

Thanks

Michal

> 
> -- Steve
> 
> > 
> > diff --git a/init/main.c b/init/main.c
> > index 1f5fdedbb293..1e5b1dc940d9 100644
> > --- a/init/main.c
> > +++ b/init/main.c
> > @@ -244,15 +244,10 @@ static int __init repair_env_string(char
> > *param, char *val, const char *unused, void *arg)
> >  {
> >  	if (val) {
> > -		/* param=val or param="val"? */
> > -		if (val == param+strlen(param)+1)
> > -			val[-1] = '=';
> > -		else if (val == param+strlen(param)+2) {
> > -			val[-2] = '=';
> > -			memmove(val-1, val, strlen(val)+1);
> > -			val--;
> > -		} else
> > -			BUG();
> > +		int parm_len = strlen(param);
> > +
> > +		param[parm_len] = '=';
> > +		BUG_ON(val != param + parm_len + 1);
> >  	}
> >  	return 0;
> >  }  
>