linux-kernel - Re: [PATCH] bootup: Add built-in kernel command line for x86

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20080811191012.GA16553@elte.hu>
Date:	Mon, 11 Aug 2008 21:10:12 +0200
From:	Ingo Molnar <mingo@...e.hu>
To:	Tim Bird <tim.bird@...sony.com>
Cc:	linux kernel <linux-kernel@...r.kernel.org>,
	linux-embedded <linux-embedded@...r.kernel.org>,
	Matt Mackall <mpm@...enic.com>,
	"H. Peter Anvin" <hpa@...or.com>,
	Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [PATCH] bootup: Add built-in kernel command line for x86


* Tim Bird <tim.bird@...sony.com> wrote:

> Add support for a built-in command line for x86 architectures. The 
> Kconfig help gives the major rationale for this addition.

i have actually used a local hack quite similar to this to inject boot 
options into bzImages via randconfig - so i would find this feature 
rather useful.

a small observation:

> +	/* append boot loader cmdline to builtin, unless builtin overrides it */
> +	if (builtin_cmdline[0] != '!') {
> +		strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
> +		strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
> +		strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
> +	} else {
> +		strlcpy(boot_command_line, &builtin_cmdline[1],
> +			COMMAND_LINE_SIZE);
> +	}

the default branch changes existing command lines slightly: it appends a 
space to them. This could break scripts that rely on the precise 
contents of /proc/cmdline output. (i have some - they are arguably 
dodgy)

Best would be to make it really apparent in the code that nothing 
changes if this config option is not set. Preferably there should be no 
extra code at all in that case.

	Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/