From: Dave Jones <davej@redhat.com>
To: Siarhei Liakh <sliakh.lkml@gmail.com>
Cc: linux-kernel@vger.kernel.org,
linux-security-module@vger.kernel.org,
linux-next@vger.kernel.org,
Arjan van de Ven <arjan@infradead.org>,
James Morris <jmorris@namei.org>,
Andrew Morton <akpm@linux-foundation.org>, Andi Kleen <ak@muc.de>,
Thomas Gleixner <tglx@linutronix.de>,
"H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@elte.hu>,
Rusty Russell <rusty@rustcorp.com.au>,
Stephen Rothwell <sfr@canb.auug.org.au>
Subject: Re: [PATCH v6] RO/NX protection for loadable kernel modules
Date: Mon, 21 Sep 2009 17:40:47 -0400 [thread overview]
Message-ID: <20090921214046.GA17243@redhat.com> (raw)
In-Reply-To: <817ecb6f0909101950v2fc6dc6u5cbc40cd9a9dde77@mail.gmail.com>
On Thu, Sep 10, 2009 at 10:50:47PM -0400, Siarhei Liakh wrote:
> This patch is a logical extension of the protection provided by
> CONFIG_DEBUG_RODATA to LKMs. The protection is provided by splitting
> module_core and module_init into three logical parts each and setting
> appropriate page access permissions for each individual section:
>
> 1. Code: RO+X
> 2. RO data: RO+NX
> 3. RW data: RW+NX
Hi Siarhei,
I tried out this patch on 2.6.31, and got the following trace during bootup..
------------[ cut here ]------------
WARNING: at kernel/trace/ftrace.c:1003 ftrace_bug+0x198/0x27e() (Not tainted)
Hardware name: VGN-Z540N
Modules linked in: output(+)
Pid: 115, comm: modprobe Not tainted 2.6.31-23.fc12.x86_64 #1
Call Trace:
[<ffffffff81064244>] warn_slowpath_common+0x95/0xc3
[<ffffffffa0000193>] ? video_output_register+0x11/0x10a [output]
[<ffffffff81064299>] warn_slowpath_null+0x27/0x3d
[<ffffffff810d4a0e>] ftrace_bug+0x198/0x27e
[<ffffffffa0000193>] ? video_output_register+0x11/0x10a [output]
[<ffffffff810d5c66>] ftrace_convert_nops+0x201/0x2b9
[<ffffffffa0000193>] ? video_output_register+0x11/0x10a [output]
[<ffffffff810d5d6a>] ftrace_module_notify+0x4c/0x7f
[<ffffffff815099c5>] notifier_call_chain+0x72/0xba
[<ffffffff81086db1>] ? __blocking_notifier_call_chain+0x4c/0x8e
[<ffffffff81086dc8>] __blocking_notifier_call_chain+0x63/0x8e
[<ffffffff81086e1a>] blocking_notifier_call_chain+0x27/0x3d
[<ffffffff810a466a>] sys_init_module+0xb7/0x249
[<ffffffff81011f42>] system_call_fastpath+0x16/0x1b
---[ end trace 95b33ebf87286ae6 ]---
ftrace faulted on writing [<ffffffffa0000193>] video_output_register+0x11/0x10a [output]
I guess ftrace is trying to NOP out something in the modules which
are marked read-only ?
Dave
next prev parent reply other threads:[~2009-09-21 21:40 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-09-11 2:50 [PATCH v6] RO/NX protection for loadable kernel modules Siarhei Liakh
2009-09-21 21:40 ` Dave Jones [this message]
2009-09-22 15:49 ` Siarhei Liakh
2009-09-22 15:49 ` Siarhei Liakh
2009-10-05 11:57 ` Siarhei Liakh
2009-10-05 11:57 ` Siarhei Liakh
2009-09-21 23:59 ` Rusty Russell
2009-09-22 15:50 ` Siarhei Liakh
2009-09-22 15:50 ` Siarhei Liakh
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=20090921214046.GA17243@redhat.com \
--to=davej@redhat.com \
--cc=ak@muc.de \
--cc=akpm@linux-foundation.org \
--cc=arjan@infradead.org \
--cc=hpa@zytor.com \
--cc=jmorris@namei.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-next@vger.kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=rusty@rustcorp.com.au \
--cc=sfr@canb.auug.org.au \
--cc=sliakh.lkml@gmail.com \
--cc=tglx@linutronix.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 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.