All of lore.kernel.org
 help / color / mirror / Atom feed
From: Andrew Morton <akpm@linux-foundation.org>
To: Emese Revfy <re.emese@gmail.com>
Cc: kernel-hardening@lists.openwall.com, pageexec@freemail.hu,
	spender@grsecurity.net, mmarek@suse.com, keescook@chromium.org,
	linux-kernel@vger.kernel.org, yamada.masahiro@socionext.com,
	linux-kbuild@vger.kernel.org, tytso@mit.edu, linux-mm@kvack.org,
	axboe@kernel.dk, viro@zeniv.linux.org.uk,
	paulmck@linux.vnet.ibm.com, mingo@redhat.com, tglx@linutronix.de,
	bart.vanassche@sandisk.com, davem@davemloft.net
Subject: Re: [PATCH v2 1/3] Add the latent_entropy gcc plugin
Date: Wed, 1 Jun 2016 12:42:27 -0700	[thread overview]
Message-ID: <20160601124227.e922af8299168c09308d5e1b@linux-foundation.org> (raw)
In-Reply-To: <20160531013145.612696c12f2ef744af739803@gmail.com>

On Tue, 31 May 2016 01:31:45 +0200 Emese Revfy <re.emese@gmail.com> wrote:

> This plugin mitigates the problem of the kernel having too little entropy during
> and after boot for generating crypto keys.
> 
> It creates a local variable in every marked function. The value of this variable is
> modified by randomly chosen operations (add, xor and rol) and
> random values (gcc generates them at compile time and the stack pointer at runtime).
> It depends on the control flow (e.g., loops, conditions).
> 
> Before the function returns the plugin writes this local variable
> into the latent_entropy global variable. The value of this global variable is
> added to the kernel entropy pool in do_one_initcall() and _do_fork().

I don't think I'm really understanding.  Won't this produce the same
value on each and every boot?

WARNING: multiple messages have this Message-ID (diff)
From: Andrew Morton <akpm@linux-foundation.org>
To: Emese Revfy <re.emese@gmail.com>
Cc: kernel-hardening@lists.openwall.com, pageexec@freemail.hu,
	spender@grsecurity.net, mmarek@suse.com, keescook@chromium.org,
	linux-kernel@vger.kernel.org, yamada.masahiro@socionext.com,
	linux-kbuild@vger.kernel.org, tytso@mit.edu, linux-mm@kvack.org,
	axboe@kernel.dk, viro@zeniv.linux.org.uk,
	paulmck@linux.vnet.ibm.com, mingo@redhat.com, tglx@linutronix.de,
	bart.vanassche@sandisk.com, davem@davemloft.net
Subject: Re: [PATCH v2 1/3] Add the latent_entropy gcc plugin
Date: Wed, 1 Jun 2016 12:42:27 -0700	[thread overview]
Message-ID: <20160601124227.e922af8299168c09308d5e1b@linux-foundation.org> (raw)
In-Reply-To: <20160531013145.612696c12f2ef744af739803@gmail.com>

On Tue, 31 May 2016 01:31:45 +0200 Emese Revfy <re.emese@gmail.com> wrote:

> This plugin mitigates the problem of the kernel having too little entropy during
> and after boot for generating crypto keys.
> 
> It creates a local variable in every marked function. The value of this variable is
> modified by randomly chosen operations (add, xor and rol) and
> random values (gcc generates them at compile time and the stack pointer at runtime).
> It depends on the control flow (e.g., loops, conditions).
> 
> Before the function returns the plugin writes this local variable
> into the latent_entropy global variable. The value of this global variable is
> added to the kernel entropy pool in do_one_initcall() and _do_fork().

I don't think I'm really understanding.  Won't this produce the same
value on each and every boot?

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

WARNING: multiple messages have this Message-ID (diff)
From: Andrew Morton <akpm@linux-foundation.org>
To: Emese Revfy <re.emese@gmail.com>
Cc: kernel-hardening@lists.openwall.com, pageexec@freemail.hu,
	spender@grsecurity.net, mmarek@suse.com, keescook@chromium.org,
	linux-kernel@vger.kernel.org, yamada.masahiro@socionext.com,
	linux-kbuild@vger.kernel.org, tytso@mit.edu, linux-mm@kvack.org,
	axboe@kernel.dk, viro@zeniv.linux.org.uk,
	paulmck@linux.vnet.ibm.com, mingo@redhat.com, tglx@linutronix.de,
	bart.vanassche@sandisk.com, davem@davemloft.net
Subject: [kernel-hardening] Re: [PATCH v2 1/3] Add the latent_entropy gcc plugin
Date: Wed, 1 Jun 2016 12:42:27 -0700	[thread overview]
Message-ID: <20160601124227.e922af8299168c09308d5e1b@linux-foundation.org> (raw)
In-Reply-To: <20160531013145.612696c12f2ef744af739803@gmail.com>

On Tue, 31 May 2016 01:31:45 +0200 Emese Revfy <re.emese@gmail.com> wrote:

> This plugin mitigates the problem of the kernel having too little entropy during
> and after boot for generating crypto keys.
> 
> It creates a local variable in every marked function. The value of this variable is
> modified by randomly chosen operations (add, xor and rol) and
> random values (gcc generates them at compile time and the stack pointer at runtime).
> It depends on the control flow (e.g., loops, conditions).
> 
> Before the function returns the plugin writes this local variable
> into the latent_entropy global variable. The value of this global variable is
> added to the kernel entropy pool in do_one_initcall() and _do_fork().

I don't think I'm really understanding.  Won't this produce the same
value on each and every boot?

  reply	other threads:[~2016-06-01 19:42 UTC|newest]

Thread overview: 62+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-05-30 23:30 [PATCH v2 0/3] Introduce the latent_entropy gcc plugin Emese Revfy
2016-05-30 23:30 ` [kernel-hardening] " Emese Revfy
2016-05-30 23:30 ` Emese Revfy
2016-05-30 23:31 ` [PATCH v2 1/3] Add " Emese Revfy
2016-05-30 23:31   ` [kernel-hardening] " Emese Revfy
2016-05-30 23:31   ` Emese Revfy
2016-06-01 19:42   ` Andrew Morton [this message]
2016-06-01 19:42     ` [kernel-hardening] " Andrew Morton
2016-06-01 19:42     ` Andrew Morton
2016-06-03 17:42     ` Emese Revfy
2016-06-03 17:42       ` [kernel-hardening] " Emese Revfy
2016-06-03 17:42       ` Emese Revfy
2016-06-06 13:38       ` [kernel-hardening] " David Brown
2016-06-06 13:38         ` David Brown
2016-06-06 15:50         ` Kees Cook
2016-06-06 15:50           ` Kees Cook
2016-06-06 15:50           ` Kees Cook
2016-06-06 19:30         ` PaX Team
2016-06-06 19:30           ` PaX Team
2016-06-06 23:13           ` Theodore Ts'o
2016-06-06 23:13             ` Theodore Ts'o
2016-06-07 12:19             ` PaX Team
2016-06-07 12:19               ` PaX Team
2016-06-07 13:58               ` Theodore Ts'o
2016-06-07 13:58                 ` Theodore Ts'o
2016-06-09 17:22                 ` PaX Team
2016-06-09 17:22                   ` PaX Team
2016-06-09 19:55                   ` Theodore Ts'o
2016-06-09 19:55                     ` Theodore Ts'o
2016-06-09 20:08                     ` Kees Cook
2016-06-09 20:08                       ` Kees Cook
2016-06-09 20:08                       ` Kees Cook
2016-06-09 21:51   ` Kees Cook
2016-06-09 21:51     ` [kernel-hardening] " Kees Cook
2016-06-09 21:51     ` Kees Cook
2016-06-09 21:51     ` Kees Cook
2016-06-13 21:49     ` Emese Revfy
2016-06-13 21:49       ` [kernel-hardening] " Emese Revfy
2016-06-13 21:49       ` Emese Revfy
2016-06-13 21:49       ` Emese Revfy
2016-06-14 18:27       ` Kees Cook
2016-06-14 18:27         ` [kernel-hardening] " Kees Cook
2016-06-14 18:27         ` Kees Cook
2016-06-14 18:27         ` Kees Cook
2016-06-14 22:31         ` Emese Revfy
2016-06-14 22:31           ` [kernel-hardening] " Emese Revfy
2016-06-14 22:31           ` Emese Revfy
2016-06-14 22:31           ` Emese Revfy
2016-05-30 23:32 ` [PATCH v2 2/3] Mark functions with the latent_entropy attribute Emese Revfy
2016-05-30 23:32   ` [kernel-hardening] " Emese Revfy
2016-05-30 23:32   ` Emese Revfy
2016-05-30 23:34 ` [PATCH v2 3/3] Add the extra_latent_entropy kernel parameter Emese Revfy
2016-05-30 23:34   ` [kernel-hardening] " Emese Revfy
2016-05-30 23:34   ` Emese Revfy
2016-06-09 21:18 ` [PATCH v2 0/3] Introduce the latent_entropy gcc plugin Kees Cook
2016-06-09 21:18   ` [kernel-hardening] " Kees Cook
2016-06-09 21:18   ` Kees Cook
2016-06-09 21:18   ` Kees Cook
2016-06-09 23:33   ` Emese Revfy
2016-06-09 23:33     ` [kernel-hardening] " Emese Revfy
2016-06-09 23:33     ` Emese Revfy
2016-06-09 23:33     ` Emese Revfy

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=20160601124227.e922af8299168c09308d5e1b@linux-foundation.org \
    --to=akpm@linux-foundation.org \
    --cc=axboe@kernel.dk \
    --cc=bart.vanassche@sandisk.com \
    --cc=davem@davemloft.net \
    --cc=keescook@chromium.org \
    --cc=kernel-hardening@lists.openwall.com \
    --cc=linux-kbuild@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mingo@redhat.com \
    --cc=mmarek@suse.com \
    --cc=pageexec@freemail.hu \
    --cc=paulmck@linux.vnet.ibm.com \
    --cc=re.emese@gmail.com \
    --cc=spender@grsecurity.net \
    --cc=tglx@linutronix.de \
    --cc=tytso@mit.edu \
    --cc=viro@zeniv.linux.org.uk \
    --cc=yamada.masahiro@socionext.com \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.