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Date: Thu, 26 Apr 2007 21:10:04 +0200 (MEST)
From: Jan Engelhardt <jengelh@linux01.gwdg.de>
To: "Eric W. Biederman" <ebiederm@xmission.com>
cc: Miklos Szeredi <miklos@szeredi.hu>, akpm@linux-foundation.org,
       serue@us.ibm.com, viro@ftp.linux.org.uk, linuxram@us.ibm.com,
       linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
       containers@lists.osdl.org, "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [patch] unprivileged mounts update
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On Apr 25 2007 11:21, Eric W. Biederman wrote:
>>
>> Why did we want to use fsuid, exactly?
>
>- Because ruid is completely the wrong thing we want mounts owned
>  by whomever's permissions we are using to perform the mount.

Think nfs. I access some nfs file as an unprivileged user. knfsd, by
nature, would run as euid=0, uid=0, but it needs fsuid=jengelh for
most permission logic to work as expected.


Jan
--