linux-kernel - Re: [PATCHv2] Make initramfs honor CONFIG_DEVTMPFS

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]

Date:   Wed, 17 May 2017 13:58:34 +1000
From:   Michael Ellerman <mpe@...erman.id.au>
To:     Rob Landley <rob@...dley.net>,
        Andrew Morton <akpm@...ux-foundation.org>
Cc:     "linux-kernel\@vger.kernel.org" <linux-kernel@...r.kernel.org>,
        Prarit Bhargava <prarit@...hat.com>,
        "Eric W. Biederman" <ebiederm@...ssion.com>,
        Yang Shi <yang.shi@...aro.org>,
        Rasmus Villemoes <linux@...musvillemoes.dk>,
        Kees Cook <keescook@...omium.org>,
        Emese Revfy <re.emese@...il.com>,
        Petr Mladek <pmladek@...e.com>,
        Fabian Frederick <fabf@...net.be>
Subject: Re: [PATCHv2] Make initramfs honor CONFIG_DEVTMPFS_MOUNT

Rob Landley <rob@...dley.net> writes:

> diff --git a/init/main.c b/init/main.c
> index f866510..9ec09ff 100644
> --- a/init/main.c
> +++ b/init/main.c
> @@ -1055,8 +1049,17 @@ static noinline void __init kernel_init_freeable(void)
>  	if (sys_access((const char __user *) ramdisk_execute_command, 0) != 0) {
>  		ramdisk_execute_command = NULL;
>  		prepare_namespace();
> +	} else if (IS_ENABLED(CONFIG_DEVTMPFS_MOUNT)) {
> +		sys_mkdir("/dev", 0755);
> +		devtmpfs_mount("/dev");
>  	}
>  
> +	/* Open the /dev/console on the rootfs, this should never fail */
> +	if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)

Sorry to pile on, but while you're moving it do you want to update this
fairly misleading comment.

It definitely can fail, eg. if /dev/console doesn't exist, or if no
console driver is registered.

cheers