Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756178AbaFPVn4 (ORCPT ); Mon, 16 Jun 2014 17:43:56 -0400 Received: from mx1.redhat.com ([209.132.183.28]:13292 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751521AbaFPVnz (ORCPT ); Mon, 16 Jun 2014 17:43:55 -0400 Date: Mon, 16 Jun 2014 17:43:13 -0400 From: Vivek Goyal To: "H. Peter Anvin" Cc: Borislav Petkov , WANG Chao , Dave Young , mjg59@srcf.ucam.org, bhe@redhat.com, jkosina@suse.cz, greg@kroah.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, ebiederm@xmission.com, akpm@linux-foundation.org Subject: Re: [PATCH 07/13] kexec: Implementation of new syscall kexec_file_load Message-ID: <20140616214313.GB1870@redhat.com> References: <20140609053538.GA2874@dhcp-17-89.nay.redhat.com> <20140609154137.GD22049@redhat.com> <20140613075011.GA4751@pd.tnic> <20140613124609.GC5871@redhat.com> <20140613153620.GG4751@pd.tnic> <20140616173823.GC4515@redhat.com> <20140616200526.GF8170@pd.tnic> <20140616205331.GA13257@redhat.com> <20140616210927.GJ8170@pd.tnic> <539F60B3.1040509@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <539F60B3.1040509@zytor.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 16, 2014 at 02:25:07PM -0700, H. Peter Anvin wrote: > On 06/16/2014 02:09 PM, Borislav Petkov wrote: > > > > Nah, I don't feel strongly about it - I just don't trust userspace and > > think that every value we get from it should be "sanitized". > > > > Borislav and I talked about this briefly over IRC. A key part of that > is that if userspace could manipulate this system call to consume an > unreasonable amount of memory, we would have a problem, for example if > this code used vzalloc() instead of kzalloc(). However, since > kmalloc/kzalloc implies a relatively restrictive limit on the memory > allocation size anyway, well short of anything that could cause OOM > problems, that pretty much solves the problem. Actually currently I am using vzalloc() for command line buffer allocation. image->cmdline_buf = vzalloc(cmdline_len); if (!image->cmdline_buf) goto out; Should I switch to using kzalloc() instead? Thanks Vivek -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/