From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arjan van de Ven Subject: Re: [PATCH] ipvs: Add boundary check on ioctl arguments Date: Thu, 1 Oct 2009 09:22:20 +0200 Message-ID: <20091001092220.2ea81cb2@infradead.org> References: <20090930131109.2b3f71b8@infradead.org> <4AC35F44.60707@google.com> <20090930171833.5ce0011d@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Hannes Eder , Wensong Zhang , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Simon Horman To: Julian Anastasov Return-path: Received: from casper.infradead.org ([85.118.1.10]:53265 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751557AbZJAVvI (ORCPT ); Thu, 1 Oct 2009 17:51:08 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Wed, 30 Sep 2009 22:41:05 +0300 (EEST) Julian Anastasov wrote: > > Hello, > > On Wed, 30 Sep 2009, Arjan van de Ven wrote: > > > fair enough; updated patch below > Later len can be checked > additionally and surely can exceed 128 (include/linux/ip_vs.h has > all user structures). the on-stack structure currently is 128 bytes though... > Can you show the exact cmd and len > used, may be there is error in some command or may be the > provided user structure is wrong? this comes from code inspection using gcc features; this is one of the (few) cases in the kernel where gcc cannot prove that the copy_from_user() length for the copy-to-stack is sufficiently bounds checked. I'm trying to make sure all these cases have complete enough checks, both for the obvious security reasons but also to be able to then make gcc emit a warning to prevent future issues from popping up. -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org