public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: ebiederm@xmission.com (Eric W. Biederman)
To: Karel Zak <kzak@redhat.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
Subject: Re: [patch 0/8]  mount ownership and unprivileged mount syscall (v4)
Date: Tue, 24 Apr 2007 19:04:36 -0600	[thread overview]
Message-ID: <m1647ltgbf.fsf@ebiederm.dsl.xmission.com> (raw)
In-Reply-To: <20070425000414.GH14086@petra.dvoda.cz> (Karel Zak's message of "Wed, 25 Apr 2007 02:04:14 +0200")

Karel Zak <kzak@redhat.com> writes:

> On Fri, Apr 20, 2007 at 12:25:32PM +0200, Miklos Szeredi wrote:
>> The following extra security measures are taken for unprivileged
>> mounts:
>> 
>>  - usermounts are limited by a sysctl tunable
>>  - force "nosuid,nodev" mount options on the created mount
>
>  The original userspace "user=" solution also implies the "noexec"
>  option by default (you can override the default by "exec" option).
>  
>  It means the kernel based solution is not fully compatible ;-(

Why noexec?  Either it was a silly or arbitrary decision, or
our kernel design may be incomplete.

Now I can see not wanting to support executables if you are locking
down a system.  The classic don't execute a program from a CD just because
the CD was stuck in the drive problem.

So I can see how executing code from an untrusted source could prevent
exploitation of other problems, and we certainly don't want to do it
automatically.

Eric

  reply	other threads:[~2007-04-25  1:06 UTC|newest]

Thread overview: 56+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-04-20 10:25 [patch 0/8] mount ownership and unprivileged mount syscall (v4) Miklos Szeredi
2007-04-20 10:25 ` [patch 1/8] add user mounts to the kernel Miklos Szeredi
2007-04-21  7:55   ` Andrew Morton
2007-04-21  8:06     ` Miklos Szeredi
2007-04-21 13:14   ` Eric W. Biederman
2007-04-22  7:02     ` Miklos Szeredi
2007-04-22  7:43       ` Eric W. Biederman
2007-04-22  8:05         ` Miklos Szeredi
2007-04-22 16:22         ` Miklos Szeredi
2007-04-20 10:25 ` [patch 2/8] allow unprivileged umount Miklos Szeredi
2007-04-21  7:55   ` Andrew Morton
2007-04-21  8:01     ` H. Peter Anvin
2007-04-21  8:09     ` Miklos Szeredi
2007-04-21  8:36       ` Andrew Morton
2007-04-21 12:53         ` Eric W. Biederman
2007-04-22  6:47           ` Miklos Szeredi
2007-04-22  7:09             ` Eric W. Biederman
2007-04-22  7:32               ` Miklos Szeredi
2007-04-21 13:29   ` Eric W. Biederman
2007-04-22  7:05     ` Miklos Szeredi
2007-04-20 10:25 ` [patch 3/8] account user mounts Miklos Szeredi
2007-04-21  7:55   ` Andrew Morton
2007-04-21 13:37   ` Eric W. Biederman
2007-04-22  7:10     ` Miklos Szeredi
2007-04-22  7:49       ` Eric W. Biederman
2007-04-22  8:08         ` Miklos Szeredi
2007-04-20 10:25 ` [patch 4/8] propagate error values from clone_mnt Miklos Szeredi
2007-04-21 13:40   ` Eric W. Biederman
2007-04-20 10:25 ` [patch 5/8] allow unprivileged bind mounts Miklos Szeredi
2007-04-21 14:00   ` Eric W. Biederman
2007-04-22  7:19     ` Miklos Szeredi
2007-04-20 10:25 ` [patch 6/8] put declaration of put_filesystem() in fs.h Miklos Szeredi
2007-04-20 10:25 ` [patch 7/8] allow unprivileged mounts Miklos Szeredi
2007-04-21  7:55   ` Andrew Morton
2007-04-21  8:13     ` Miklos Szeredi
2007-04-21  8:23       ` Miklos Szeredi
2007-04-21 14:10     ` Eric W. Biederman
2007-04-21 15:43       ` Jan Engelhardt
2007-04-21 16:57         ` Eric W. Biederman
2007-04-21 17:10           ` Jan Engelhardt
2007-04-21 21:00             ` Eric W. Biederman
2007-04-22  8:19               ` Miklos Szeredi
2007-04-21 22:06     ` Andi Kleen
2007-04-21 21:33       ` Eric W. Biederman
2007-04-22  0:46     ` Shaya Potter
2007-04-20 10:25 ` [patch 8/8] allow unprivileged fuse mounts Miklos Szeredi
2007-04-21  7:55   ` Andrew Morton
2007-04-21  8:16     ` Miklos Szeredi
2007-04-21 14:18   ` Eric W. Biederman
2007-04-22  7:22     ` Miklos Szeredi
2007-04-20 12:42 ` [patch 0/8] mount ownership and unprivileged mount syscall (v4) Serge E. Hallyn
2007-04-20 16:33   ` Eric W. Biederman
2007-04-25  0:04 ` Karel Zak
2007-04-25  1:04   ` Eric W. Biederman [this message]
2007-04-25  7:18   ` Miklos Szeredi
2007-04-25  9:23     ` Karel Zak

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=m1647ltgbf.fsf@ebiederm.dsl.xmission.com \
    --to=ebiederm@xmission.com \
    --cc=akpm@linux-foundation.org \
    --cc=containers@lists.osdl.org \
    --cc=kzak@redhat.com \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxram@us.ibm.com \
    --cc=miklos@szeredi.hu \
    --cc=serue@us.ibm.com \
    --cc=viro@ftp.linux.org.uk \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox