linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
To: "ebiggers@google.com" <ebiggers@google.com>,
	"mingo@kernel.org" <mingo@kernel.org>,
	"peterz@infradead.org" <peterz@infradead.org>,
	"keescook@chromium.org" <keescook@chromium.org>,
	"Reshetova, Elena" <elena.reshetova@intel.com>,
	"ebiggers3@gmail.com" <ebiggers3@gmail.com>,
	"David.Laight@ACULAB.COM" <David.Laight@ACULAB.COM>,
	"tytso@mit.edu" <tytso@mit.edu>,
	"herbert@gondor.apana.org.au" <herbert@gondor.apana.org.au>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"daniel@iogearbox.net" <daniel@iogearbox.net>,
	"jannh@google.com" <jannh@google.com>,
	"tglx@linutronix.de" <tglx@linutronix.de>,
	"jpoimboe@redhat.com" <jpoimboe@redhat.com>,
	"mingo@redhat.com" <mingo@redhat.com>,
	"luto@kernel.org" <luto@kernel.org>,
	"bp@alien8.de" <bp@alien8.de>,
	"gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>,
	"luto@amacapital.net" <luto@amacapital.net>,
	"Perla, Enrico" <enrico.perla@intel.com>
Subject: Re: [PATCH] x86/entry/64: randomize kernel stack offset upon syscall
Date: Fri, 26 Apr 2019 17:37:34 +0000	[thread overview]
Message-ID: <56e694bfbe2993389a9662b1477b74eaaca3c171.camel@intel.com> (raw)
In-Reply-To: <2236FBA76BA1254E88B949DDB74E612BA4C63E24@IRSMSX102.ger.corp.intel.com>

On Fri, 2019-04-26 at 12:33 +0100, Reshetova, Elena wrote:
> 1) rdtsc or variations based on it (David proposed some CRC-based variants for
> > example)
Hi,

Could we repeatedly measure the time for a short syscall on a quiet system and
estimate the entropy we get from this? In some scenarios the attacker might have
less control of the timing as well.

Since this is a statistical defense, assuming the argument can be made that
there is at least some randomness in the timer, and could at least be out of the
control of an attacker sometimes, I wonder if this feature could be valuable
before the search for a faster stronger random number generator completes.

Could that be a way forward for now?

Thanks,

Rick

  parent reply	other threads:[~2019-04-26 17:37 UTC|newest]

Thread overview: 81+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-04-15  6:09 [PATCH] x86/entry/64: randomize kernel stack offset upon syscall Elena Reshetova
2019-04-15  7:25 ` Ingo Molnar
2019-04-15  8:44   ` Reshetova, Elena
2019-04-16  7:34     ` Ingo Molnar
2019-04-16 11:10       ` Reshetova, Elena
2019-04-16 12:08         ` Peter Zijlstra
2019-04-16 12:45           ` David Laight
2019-04-16 15:43             ` Theodore Ts'o
2019-04-16 16:07               ` Peter Zijlstra
2019-04-16 16:47               ` Reshetova, Elena
2019-04-17  9:28                 ` David Laight
2019-04-17 15:15                   ` Theodore Ts'o
2019-04-17 15:40                     ` Kees Cook
2019-04-17 15:53                     ` David Laight
2019-04-24 11:42                       ` Reshetova, Elena
2019-04-24 13:33                         ` David Laight
2019-04-25 11:23                           ` Reshetova, Elena
2019-04-26 11:33                         ` Reshetova, Elena
2019-04-26 14:01                           ` Theodore Ts'o
2019-04-26 17:44                             ` Eric Biggers
2019-04-26 18:02                               ` Theodore Ts'o
2019-04-27 13:59                                 ` Andy Lutomirski
2019-04-29  8:04                               ` Reshetova, Elena
2019-04-26 18:34                             ` Andy Lutomirski
2019-04-29  7:46                               ` Reshetova, Elena
2019-04-29 16:08                                 ` Andy Lutomirski
2019-04-30 17:51                                   ` Reshetova, Elena
2019-04-30 18:01                                     ` Kees Cook
2019-05-01  8:23                                     ` David Laight
2019-05-02  8:07                                       ` Reshetova, Elena
2019-05-01  8:41                                     ` David Laight
2019-05-01 23:33                                       ` Andy Lutomirski
2019-05-02  8:15                                       ` Reshetova, Elena
2019-05-02  9:23                                         ` David Laight
2019-05-02 14:47                                           ` Andy Lutomirski
2019-05-02 15:08                                             ` Ingo Molnar
2019-05-02 16:32                                               ` Andy Lutomirski
2019-05-02 16:43                                                 ` Ingo Molnar
2019-05-03 16:40                                                   ` Andy Lutomirski
2019-05-02 16:34                                               ` David Laight
2019-05-02 16:45                                                 ` Ingo Molnar
2019-05-03 16:17                                                   ` Reshetova, Elena
2019-05-03 16:40                                                     ` David Laight
2019-05-03 19:10                                                       ` Linus Torvalds
2019-05-06  6:47                                                         ` Reshetova, Elena
2019-05-06  7:01                                                       ` Reshetova, Elena
2019-05-08 11:18                                                       ` Reshetova, Elena
2019-05-08 11:32                                                         ` Ingo Molnar
2019-05-08 13:22                                                           ` Reshetova, Elena
2019-05-09  5:59                                                             ` Ingo Molnar
2019-05-09  7:01                                                               ` Reshetova, Elena
2019-05-09  8:43                                                                 ` Ingo Molnar
2019-05-11 22:45                                                                   ` Andy Lutomirski
2019-05-12  0:12                                                                     ` Kees Cook
2019-05-12  8:02                                                                       ` Ingo Molnar
2019-05-12 14:33                                                                         ` Kees Cook
2019-05-28 12:28                                                                           ` Reshetova, Elena
2019-05-28 13:33                                                                             ` Theodore Ts'o
2019-05-29 10:13                                                                               ` Reshetova, Elena
2019-05-29 10:51                                                                                 ` David Laight
2019-05-29 18:35                                                                                 ` Kees Cook
2019-05-29 18:37                                                                                 ` Kees Cook
2019-07-29 11:41                                                                                   ` Reshetova, Elena
2019-07-30 18:07                                                                                     ` Kees Cook
2019-08-01  6:35                                                                                     ` Reshetova, Elena
2019-05-09  7:03                                                               ` Reshetova, Elena
2019-05-06  7:32                                               ` Reshetova, Elena
2019-04-29  7:49                             ` Reshetova, Elena
2019-04-26 17:37                           ` Edgecombe, Rick P [this message]
2019-04-17  6:24               ` Ingo Molnar
2019-04-16 18:19           ` Reshetova, Elena
     [not found] <20190408061358.21288-1-elena.reshetova@intel.com>
2019-04-08 12:49 ` Josh Poimboeuf
2019-04-08 13:30   ` Reshetova, Elena
2019-04-08 16:21     ` Kees Cook
2019-04-10  8:26   ` Ingo Molnar
2019-04-10  9:00     ` Reshetova, Elena
2019-04-10 10:17       ` Ingo Molnar
2019-04-10 10:24       ` Reshetova, Elena
2019-04-10 14:52         ` Andy Lutomirski
2019-04-12  5:36           ` Reshetova, Elena
2019-04-12 21:16             ` Andy Lutomirski

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=56e694bfbe2993389a9662b1477b74eaaca3c171.camel@intel.com \
    --to=rick.p.edgecombe@intel.com \
    --cc=David.Laight@ACULAB.COM \
    --cc=bp@alien8.de \
    --cc=daniel@iogearbox.net \
    --cc=ebiggers3@gmail.com \
    --cc=ebiggers@google.com \
    --cc=elena.reshetova@intel.com \
    --cc=enrico.perla@intel.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=herbert@gondor.apana.org.au \
    --cc=jannh@google.com \
    --cc=jpoimboe@redhat.com \
    --cc=keescook@chromium.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luto@amacapital.net \
    --cc=luto@kernel.org \
    --cc=mingo@kernel.org \
    --cc=mingo@redhat.com \
    --cc=peterz@infradead.org \
    --cc=tglx@linutronix.de \
    --cc=tytso@mit.edu \
    /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;
as well as URLs for NNTP newsgroup(s).