From: Daniel Micay <danielmicay@gmail.com>
To: Kostya Serebryany <kcc@google.com>, Kees Cook <keescook@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>,
Michal Hocko <mhocko@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
"linux-mm@kvack.org" <linux-mm@kvack.org>,
Rik van Riel <riel@redhat.com>, Reid Kleckner <rnk@google.com>,
Peter Collingbourne <pcc@google.com>,
eugenis@google.com
Subject: Re: binfmt_elf: use ELF_ET_DYN_BASE only for PIE breaks asan
Date: Mon, 07 Aug 2017 14:45:56 -0400 [thread overview]
Message-ID: <1502131556.1803.10.camel@gmail.com> (raw)
In-Reply-To: <1502131092.1803.8.camel@gmail.com>
> There are currently other issues. Try:
>
> sysctl vm.mmap_rnd_bits=32
> sysctl vm.mmap_rnd_compat_bits=16
>
> IIRC that breaks some sanitizers at least for 32-bit executables.
Also, stack mapping rand isn't yet tied to that sysctl but is rather
hard-wired to 11 bits on 32-bit and 20 bits (IIRC) on 64-bit. Once it's
tied to the sysctl (or a different sysctl, if keeping the same defaults
is desired) that will be able to use significantly more address space.
It might be setting it to the maximum + better stack rand that breaks
sanitizers, rather than just setting the entropy higher.
If anyone wants to test some other changes though...
https://github.com/copperhead/linux-hardened/commit/31ebed471d31a437cc551b1bfae03c9e7f58117d.patch
https://github.com/copperhead/linux-hardened/commit/073329e7b541b89172833f61fb84d81f32389d6e.patch
They haven't been submitted for inclusion upstream, but that's the plan:
reaching parity with the ASLR PaX has provided for years when the
entropy values are set to max.
--
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>
next prev parent reply other threads:[~2017-08-07 18:45 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-07 17:24 binfmt_elf: use ELF_ET_DYN_BASE only for PIE breaks asan Dmitry Vyukov
2017-08-07 17:33 ` Kostya Serebryany
2017-08-07 17:33 ` Kees Cook
2017-08-07 18:26 ` Kostya Serebryany
2017-08-07 18:36 ` Evgenii Stepanov
2017-08-07 18:40 ` Kees Cook
2017-08-07 18:51 ` Evgenii Stepanov
2017-08-07 18:57 ` Kees Cook
2017-08-07 19:03 ` Kostya Serebryany
2017-08-07 19:06 ` Kees Cook
2017-08-07 19:10 ` Kostya Serebryany
2017-08-07 19:24 ` Kees Cook
2017-08-07 19:32 ` Kostya Serebryany
2017-08-07 19:12 ` Evgenii Stepanov
2017-08-07 18:38 ` Daniel Micay
2017-08-07 18:45 ` Daniel Micay [this message]
2017-08-07 18:39 ` Kees Cook
2017-08-07 18:48 ` Daniel Micay
2017-08-07 18:52 ` Kees Cook
2017-08-07 18:56 ` Kostya Serebryany
2017-08-07 18:59 ` Kees Cook
2017-08-07 19:01 ` Daniel Micay
2017-08-07 19:05 ` Kostya Serebryany
2017-08-07 19:12 ` Kees Cook
2017-08-07 19:16 ` Kostya Serebryany
2017-08-07 19:21 ` Kees Cook
2017-08-07 19:26 ` Kostya Serebryany
2017-08-07 19:34 ` Kees Cook
2017-08-07 19:40 ` Kostya Serebryany
2017-08-07 19:42 ` Daniel Micay
2017-08-07 19:46 ` Kees Cook
2017-08-07 18:21 ` Daniel Micay
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=1502131556.1803.10.camel@gmail.com \
--to=danielmicay@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=dvyukov@google.com \
--cc=eugenis@google.com \
--cc=kcc@google.com \
--cc=keescook@google.com \
--cc=linux-mm@kvack.org \
--cc=mhocko@kernel.org \
--cc=pcc@google.com \
--cc=riel@redhat.com \
--cc=rnk@google.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.