Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267566AbUIULX0 (ORCPT ); Tue, 21 Sep 2004 07:23:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267568AbUIULX0 (ORCPT ); Tue, 21 Sep 2004 07:23:26 -0400 Received: from gprs214-92.eurotel.cz ([160.218.214.92]:4995 "EHLO amd.ucw.cz") by vger.kernel.org with ESMTP id S267566AbUIULXZ (ORCPT ); Tue, 21 Sep 2004 07:23:25 -0400 Date: Tue, 21 Sep 2004 13:19:00 +0200 From: Pavel Machek To: Stas Sergeev Cc: Denis Vlasenko , linux-kernel@vger.kernel.org Subject: Re: ESP corruption bug - what CPUs are affected? Message-ID: <20040921111900.GA7515@elf.ucw.cz> References: <4149D243.5050501@aknet.ru> <200409162203.17988.vda@port.imtp.ilyichevsk.odessa.ua> <414B2949.700@aknet.ru> <200409180104.09796.vda@port.imtp.ilyichevsk.odessa.ua> <414C14CD.7030200@aknet.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <414C14CD.7030200@aknet.ru> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.5.1+cvs20040105i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 911 Lines: 22 Hi! > >for subsequent push/pop/call/ret operations. > >But if code uses full ESP, thinking that upper 16 bits are zero, > >it will crash badly. Correct me if I'm wrong. > That's correct. But you should note that the > program not just "thinks" that the upper 16 bits > are zero. It writes zero there itself, and a few > instructions later - oops, it is no longer zero... Hmm, perhaps this can also be viewed as a "information leak"? Program running under dosemu is not expected to know high bits of kernel %esp... Pavel -- People were complaining that M$ turns users into beta-testers... ...jr ghea gurz vagb qrirybcref, naq gurl frrz gb yvxr vg gung jnl! - 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/