linux-kernel - Re: [PATCH] Consolidate CONFIG_DEBUG_STRICT_USER_COPY

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <512E8ECF.1080307@zytor.com>
Date:	Wed, 27 Feb 2013 14:55:11 -0800
From:	"H. Peter Anvin" <hpa@...or.com>
To:	Stephen Boyd <sboyd@...eaurora.org>
CC:	Arnd Bergmann <arnd@...db.de>,
	Andrew Morton <akpm@...ux-foundation.org>,
	linux-kernel@...r.kernel.org, Ingo Molnar <mingo@...e.hu>,
	linux-parisc@...r.kernel.org, linux-s390@...r.kernel.org,
	Arjan van de Ven <arjan@...ux.intel.com>,
	Helge Deller <deller@....de>,
	Heiko Carstens <heiko.carstens@...ibm.com>,
	Stephen Rothwell <sfr@...b.auug.org.au>,
	Chris Metcalf <cmetcalf@...era.com>
Subject: Re: [PATCH] Consolidate CONFIG_DEBUG_STRICT_USER_COPY_CHECK

On 02/27/2013 02:52 PM, Stephen Boyd wrote:
> On 02/27/13 14:19, H. Peter Anvin wrote:
>> On 02/27/2013 12:42 PM, Stephen Boyd wrote:
>>>> It's fine to do your patch as a first step though, which would not
>>>> change the behavior.
>>> A lot of arches seem to not want to enable it because false positives
>>> are everywhere. It really depends on how good the compiler is at doing
>>> constant propagation and dead code removal.
>>>
>> Although some of the cases I have seen being flagged as "false
>> positives" have been real bugs.
> 
> There were so many false-positives on x86_64 that Andrew eventually
> dropped my patch to add support for this option to the copy_from_user()
> function there.
> 

I would probably have taken it, especially if it came with more x86-64
to i386 unification.

It's an option, though.

	-hpa

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/