From: "H. Peter Anvin" <hpa@zytor.com>
To: castet.matthieu@free.fr
Cc: Ingo Molnar <mingo@elte.hu>,
Linux Kernel list <linux-kernel@vger.kernel.org>,
linux-security-module@vger.kernel.org,
Matthias Hopf <mhopf@suse.de>,
rjw@sisk.pl, Andrew Morton <akpm@linux-foundation.org>,
Suresh Siddha <suresh.b.siddha@intel.com>
Subject: Re: [PATCH] NX protection for kernel data : fix 32 bits S3 suspend
Date: Mon, 07 Feb 2011 12:04:45 -0800 [thread overview]
Message-ID: <4D50505D.2070402@zytor.com> (raw)
In-Reply-To: <1297108754.4d504f1281802@imp.free.fr>
On 02/07/2011 11:59 AM, castet.matthieu@free.fr wrote:
> For .39 I hope we could remove most of the RWX rights after init (This means
> make low memory trampoline NX or !RW).
> This should be possible on :
> - 32 bit if wakeup use trampoline_32 [1] that doesn't enable paging in low
> memory (can be NX)
> - trampoline_64 need fix to support NX on data section. It tries to read data
> section before enabling NX. A possible fix is to use its own page table [2]. And
> the kernel one can be NX.
No, you're really barking down the wrong path on this. The trampoline
code is tiny; I don't think it is really worth trying to NX-ify it. The
additional complexity caused by not being able to execute in this space
will really damage some other incoming code, so it isn't an option as
far as I'm concerned.
-hpa
next prev parent reply other threads:[~2011-02-07 20:06 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-01-31 23:03 [PATCH] NX protection for kernel data : fix 32 bits S3 suspend matthieu castet
2011-02-01 8:02 ` Ingo Molnar
2011-02-01 13:25 ` castet.matthieu
2011-02-01 16:30 ` H. Peter Anvin
2011-02-02 6:26 ` Ingo Molnar
2011-02-03 22:11 ` H. Peter Anvin
2011-02-05 1:12 ` H. Peter Anvin
2011-02-05 16:46 ` castet.matthieu
2011-02-06 23:41 ` H. Peter Anvin
2011-02-07 7:40 ` Ingo Molnar
2011-02-07 19:59 ` castet.matthieu
2011-02-07 20:04 ` H. Peter Anvin [this message]
2011-02-12 16:10 ` matthieu castet
2011-02-14 20:55 ` H. Peter Anvin
2011-02-26 3:58 ` Pavel Machek
2011-02-07 20:07 ` H. Peter Anvin
2011-02-14 21:19 ` H. Peter Anvin
2011-02-14 22:50 ` Rafael J. Wysocki
2011-02-07 3:56 ` H. Peter Anvin
2011-02-07 5:16 ` H. Peter Anvin
2011-02-07 9:24 ` [tip:x86/urgent] x86, nx: Mark the ACPI resume trampoline code as +x tip-bot for H. Peter Anvin
2011-02-07 14:50 ` [tip:x86/urgent] x86, nx: Mark the ACPI resume trampoline code as +x - fixed Marc Koschewski
2011-02-07 15:04 ` Ingo Molnar
2011-02-07 13:16 ` [PATCH] NX protection for kernel data : fix 32 bits S3 suspend Matthias Hopf
[not found] <ghb2G-3tw-7@gated-at.bofh.it>
[not found] ` <ghjtg-WV-5@gated-at.bofh.it>
[not found] ` <ghosV-TN-9@gated-at.bofh.it>
[not found] ` <ghEo1-2IF-1@gated-at.bofh.it>
[not found] ` <gifGW-7eL-13@gated-at.bofh.it>
2011-02-06 10:30 ` Bodo Eggert
2011-02-06 23:32 ` H. Peter Anvin
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=4D50505D.2070402@zytor.com \
--to=hpa@zytor.com \
--cc=akpm@linux-foundation.org \
--cc=castet.matthieu@free.fr \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=mhopf@suse.de \
--cc=mingo@elte.hu \
--cc=rjw@sisk.pl \
--cc=suresh.b.siddha@intel.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox