From: Daniel Colascione <dancol@dancol.org>
To: Paul Eggert <eggert@cs.ucla.edu>, Eli Zaretskii <eliz@gnu.org>,
emacs-devel@gnu.org
Subject: Re: Two issues with stack overflow protection
Date: Wed, 29 Jul 2015 04:27:21 -0700 [thread overview]
Message-ID: <55B8B899.8020508@dancol.org> (raw)
In-Reply-To: <55B87B84.4000105@cs.ucla.edu>
[-- Attachment #1: Type: text/plain, Size: 499 bytes --]
On 07/29/2015 12:06 AM, Paul Eggert wrote:
> Daniel Colascione wrote:
>> What's wrong with just mprotecting a guard page at the end of the stack,
>> and on overflow, giving that region normal protection, unwinding as
>> normal, then, at top level, restoring the guard page?
>
> Unwinding can grow the stack.
Sure. That's why you open up more stack to do the unwinding. Having done
that, if you still overflow, just abort. At that point, you can't
guarantee correct program semantics.
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]
next prev parent reply other threads:[~2015-07-29 11:27 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-28 17:23 Two issues with stack overflow protection Eli Zaretskii
2015-07-29 5:01 ` Paul Eggert
2015-07-29 6:10 ` Daniel Colascione
2015-07-29 7:06 ` Paul Eggert
2015-07-29 11:27 ` Daniel Colascione [this message]
2015-07-29 13:18 ` Paul Eggert
2015-07-29 16:24 ` Eli Zaretskii
2015-07-29 16:48 ` Paul Eggert
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
List information: https://www.gnu.org/software/emacs/
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=55B8B899.8020508@dancol.org \
--to=dancol@dancol.org \
--cc=eggert@cs.ucla.edu \
--cc=eliz@gnu.org \
--cc=emacs-devel@gnu.org \
/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.
Code repositories for project(s) associated with this public inbox
https://git.savannah.gnu.org/cgit/emacs.git
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 read-only IMAP folder(s) and NNTP newsgroup(s).