From: Dave Jones <davej@redhat.com>
To: Marcus Meissner <meissner@suse.de>
Cc: linux-kernel@vger.kernel.org, akpm@osdl.org
Subject: Re: [PATCH] binfmt_elf: randomize PIE binaries
Date: Thu, 19 Oct 2006 16:23:54 -0400 [thread overview]
Message-ID: <20061019202354.GI26530@redhat.com> (raw)
In-Reply-To: <20061019143547.GA8586@suse.de>
On Thu, Oct 19, 2006 at 04:35:47PM +0200, Marcus Meissner wrote:
> --- linux-2.6.18/fs/binfmt_elf.c.xx 2006-10-19 11:21:49.000000000 +0200
> +++ linux-2.6.18/fs/binfmt_elf.c 2006-10-19 11:24:58.000000000 +0200
> @@ -856,7 +856,12 @@ static int load_elf_binary(struct linux_
> * default mmap base, as well as whatever program they
> * might try to exec. This is because the brk will
> * follow the loader, and is not movable. */
> - load_bias = ELF_PAGESTART(ELF_ET_DYN_BASE - vaddr);
> + if (current->flags & PF_RANDOMIZE)
> + load_bias = randomize_range(0, ELF_ET_DYN_BASE,
> + vaddr);
> + else
> + load_bias = ELF_ET_DYN_BASE - vaddr;
> + load_bias = ELF_PAGESTART(load_bias);
> }
>
> error = elf_map(bprm->file, load_bias + vaddr, elf_ppnt,
vaddr seems odd to be using as the len for randomize_range doesn't it ?
Should that be randomize_range(0, ELF_ET_DYN_BASE, ELF_ET_DYN_BASE - vaddr);
maybe ?
Also, when we get to the elf_map(), we add vaddr back again, but in the
randomize_range case, we never subtracted it. hmm?
Dave
--
http://www.codemonkey.org.uk
next prev parent reply other threads:[~2006-10-19 20:24 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-10-19 14:35 [PATCH] binfmt_elf: randomize PIE binaries Marcus Meissner
2006-10-19 20:23 ` Dave Jones [this message]
2006-10-20 11:54 ` Marcus Meissner
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=20061019202354.GI26530@redhat.com \
--to=davej@redhat.com \
--cc=akpm@osdl.org \
--cc=linux-kernel@vger.kernel.org \
--cc=meissner@suse.de \
/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