From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966519AbcCPKwc (ORCPT ); Wed, 16 Mar 2016 06:52:32 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:34715 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965768AbcCPKw3 (ORCPT ); Wed, 16 Mar 2016 06:52:29 -0400 Date: Wed, 16 Mar 2016 11:52:26 +0100 From: Pavel Machek To: Chris Bainbridge Cc: bp@alien8.de, x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] x86/microcode: Change checksum to u32 Message-ID: <20160316105226.GB21259@amd> References: <1456570907-5344-1-git-send-email-chris.bainbridge@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1456570907-5344-1-git-send-email-chris.bainbridge@gmail.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi! > Checksum should be unsigned 32-bit otherwise the calculation overflows > resulting in undefined behaviour: > @@ -49,7 +49,7 @@ int microcode_sanity_check(void *mc, int print_err) > unsigned long total_size, data_size, ext_table_size; > struct microcode_header_intel *mc_header = mc; > struct extended_sigtable *ext_header = NULL; > - int sum, orig_sum, ext_sigcount = 0, i; > + u32 sum, orig_sum, ext_sigcount = 0, i; Ok, but what about i and ext_sigcount? Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html