From: "H. Peter Anvin" <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>
To: Andy Lutomirski <luto-kltTT9wpgjJwATOyAt5JVQ@public.gmane.org>,
"Eric W. Biederman"
<ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>,
Julien Tinnes <jln-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>,
David Drysdale <drysdale-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>,
Al Viro <viro-RmSDqhL/yNMiFSDQTTA3OLVCufUGDwFn@public.gmane.org>,
Paolo Bonzini <pbonzini-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>,
LSM List
<linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
Greg Kroah-Hartman
<gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>,
Paul Moore <paul-r2n+y4ga6xFZroRs9YW3xA@public.gmane.org>,
James Morris
<james.l.morris-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>,
Linux API <linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
Meredydd Luff <meredydd-zPN50pYk8eUaUu29zAJCuw@public.gmane.org>,
Christoph Hellwig <hch-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>,
"linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
<linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
Kees Cook <keescook-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>,
Theodore Ts'o <tytso-3s7WtUTddSA@public.gmane.org>,
Henrique de Moraes Holschuh
<hmh-N3TV7GIv+o9fyO9Q7EP/yw@public.gmane.org>,
linux-crypto-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: General flags to turn things off (getrandom, pid lookup, etc)
Date: Fri, 25 Jul 2014 16:43:20 -0700 [thread overview]
Message-ID: <53D2EB98.3090802@zytor.com> (raw)
In-Reply-To: <CALCETrWGvBfrX1W5XaFgJZhKHLf+oac9YrwPR3ppK=deQtu5hA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
On 07/25/2014 11:30 AM, Andy Lutomirski wrote:
> - 32-bit GDT code segments [huge attack surface]
> - 64-bit GDT code segments [probably pointless]
I presume you mean s/GDT/LDT/.
We already don't allow 64-bit LDT code segments. Also, it is unclear to
me how 32-bit LDT segments have a huge attack surface, given that there
will realistically always be a 32-bit *GDT* segment present.
-hpa
WARNING: multiple messages have this Message-ID (diff)
From: "H. Peter Anvin" <hpa@zytor.com>
To: Andy Lutomirski <luto@amacapital.net>,
"Eric W. Biederman" <ebiederm@xmission.com>,
Julien Tinnes <jln@google.com>,
David Drysdale <drysdale@google.com>,
Al Viro <viro@zeniv.linux.org.uk>,
Paolo Bonzini <pbonzini@redhat.com>,
LSM List <linux-security-module@vger.kernel.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Paul Moore <paul@paul-moore.com>,
James Morris <james.l.morris@oracle.com>,
Linux API <linux-api@vger.kernel.org>,
Meredydd Luff <meredydd@senatehouse.org>,
Christoph Hellwig <hch@infradead.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Kees Cook <keescook@chromium.org>,
"Theodore Ts'o" <tytso@mit.edu>,
Henrique de Moraes Holschuh <hmh@hmh.eng.br>,
linux-crypto@vger.kernel.org
Subject: Re: General flags to turn things off (getrandom, pid lookup, etc)
Date: Fri, 25 Jul 2014 16:43:20 -0700 [thread overview]
Message-ID: <53D2EB98.3090802@zytor.com> (raw)
In-Reply-To: <CALCETrWGvBfrX1W5XaFgJZhKHLf+oac9YrwPR3ppK=deQtu5hA@mail.gmail.com>
On 07/25/2014 11:30 AM, Andy Lutomirski wrote:
> - 32-bit GDT code segments [huge attack surface]
> - 64-bit GDT code segments [probably pointless]
I presume you mean s/GDT/LDT/.
We already don't allow 64-bit LDT code segments. Also, it is unclear to
me how 32-bit LDT segments have a huge attack surface, given that there
will realistically always be a 32-bit *GDT* segment present.
-hpa
next prev parent reply other threads:[~2014-07-25 23:43 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-07-25 18:30 General flags to turn things off (getrandom, pid lookup, etc) Andy Lutomirski
2014-07-25 20:15 ` Dave Jones
[not found] ` <20140725201507.GA23410-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2014-07-25 20:21 ` Andy Lutomirski
2014-07-25 20:21 ` Andy Lutomirski
[not found] ` <CALCETrWGvBfrX1W5XaFgJZhKHLf+oac9YrwPR3ppK=deQtu5hA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2014-07-25 21:35 ` One Thousand Gnomes
2014-07-25 21:35 ` One Thousand Gnomes
2014-07-25 21:41 ` Andy Lutomirski
2014-07-26 19:48 ` Eric W. Biederman
2014-07-26 19:48 ` Eric W. Biederman
2014-07-30 14:37 ` One Thousand Gnomes
2014-07-25 23:43 ` H. Peter Anvin [this message]
2014-07-25 23:43 ` H. Peter Anvin
2014-07-25 23:54 ` Andy Lutomirski
2014-07-27 12:26 ` David Drysdale
2014-07-27 12:26 ` David Drysdale
2014-07-27 21:06 ` Theodore Ts'o
2014-07-27 22:17 ` Andy Lutomirski
[not found] ` <CALCETrXfzOZEC3mOKkm3_GvitvkEu4kAa3LowRv-fjHnzrQnBg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2014-07-27 23:53 ` Eric W. Biederman
2014-07-27 23:53 ` Eric W. Biederman
2014-07-27 23:53 ` Eric W. Biederman
2014-07-30 14:37 ` One Thousand Gnomes
2014-07-30 14:37 ` One Thousand Gnomes
2014-07-30 18:41 ` Eric W. Biederman
2014-07-30 18:41 ` Eric W. Biederman
2014-07-30 21:29 ` One Thousand Gnomes
2014-07-30 21:29 ` One Thousand Gnomes
2014-07-31 2:37 ` Eric W. Biederman
2014-07-31 2:37 ` Eric W. Biederman
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