linux-kernel - Re: [RFC] situation with csum_and_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: <20141119.161744.1661940121298888832.davem@davemloft.net>
Date:	Wed, 19 Nov 2014 16:17:44 -0500 (EST)
From:	David Miller <davem@...emloft.net>
To:	torvalds@...ux-foundation.org
Cc:	viro@...iv.linux.org.uk, netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [RFC] situation with csum_and_copy_... API

From: Linus Torvalds <torvalds@...ux-foundation.org>
Date: Wed, 19 Nov 2014 12:40:53 -0800

> On Wed, Nov 19, 2014 at 12:31 PM, David Miller <davem@...emloft.net> wrote:
>>
>> But that is just my opinion, and yes I do acknowledge that we've had
>> serious holes in this area in the past.
> 
> The serious holes have generally been exactly in the "upper layers
> already check" camp, and then it turns out that some odd ioctl or
> other thing ends up doing something odd and interesting.
> 
> If Al has actual performance profiles showing that the access_ok() is
> a real problem, then fine. As a low-level optimization, I agree with
> it. But not as a "let's just drop them, and make the security rules be
> non-local and subtle, and require people to know the details of the
> whole call-chain".
> 
> Seeing a "__get_user()" and just being able to glance up in the same
> function and seeing the "access_ok()" is just a good safety net. And
> means that people don't have to waste time thinking about or looking
> for where the hell the security net really is.

Fair enough.
--
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/