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Date: Sat, 31 Mar 2012 17:51:13 +0400
From: Vasiliy Kulikov <segoon@openwall.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Arkadiusz =?utf-8?Q?Mi=C5=9Bkiewicz?= <a.miskiewicz@gmail.com>,
        linux-kernel@vger.kernel.org, Alexey Dobriyan <adobriyan@gmail.com>
Subject: Re: [PATCH] proc: fix mount -t proc -o AAA
Message-ID: <20120331135113.GA2845@albatros>
References: <201203220903.15360.a.miskiewicz@gmail.com>
 <20120323171058.GA3279@albatros>
 <20120323161504.dced28b9.akpm@linux-foundation.org>
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On Fri, Mar 23, 2012 at 16:15 -0700, Andrew Morton wrote:
> From: Vasiliy Kulikov <segoon@openwall.com>
> Subject: proc: fix mount -t proc -o AAA
> 
> The proc_parse_options() call from proc_mount() runs only once at boot
> time.  So on any later mount attempt, any mount options are ignored
> because ->s_root is already initialized.
> 
> As a consequence, "mount -o remount,<options>" will ignore the options.

s/-o remount,<options>/-o <options>/

> To fix this, parse the mount options unconditionally.
> 
> Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>

So, it should look like:

---
The proc_parse_options() call from proc_mount() runs only once at boot
time.  So on any later mount attempt, any mount options are ignored
because ->s_root is already initialized.

As a consequence, "mount -o <options>" will ignore the options.  The only
way to change mount options is "mount -o remount,<options>".

To fix this, parse the mount options unconditionally.
---

Thanks,

-- 
Vasiliy Kulikov
http://www.openwall.com - bringing security into open computing environments