From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1SclPC-0007QB-UV for user-mode-linux-devel@lists.sourceforge.net; Thu, 07 Jun 2012 22:42:14 +0000 Received: from mail-lpp01m010-f47.google.com ([209.85.215.47]) by sog-mx-3.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1SclPC-0002wg-6X for user-mode-linux-devel@lists.sourceforge.net; Thu, 07 Jun 2012 22:42:14 +0000 Received: by lags15 with SMTP id s15so955034lag.34 for ; Thu, 07 Jun 2012 15:42:07 -0700 (PDT) Message-ID: <4FD12E3D.7050401@gmail.com> Date: Fri, 08 Jun 2012 01:42:05 +0300 From: =?ISO-8859-1?Q?Martin_P=E4rtel?= MIME-Version: 1.0 References: <4FD1164B.6060307@gmail.com> <4FD11C88.6090308@nod.at> <4FD11F90.5080407@gmail.com> <4FD1263B.5070208@nod.at> In-Reply-To: <4FD1263B.5070208@nod.at> List-Id: The user-mode Linux development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Errors-To: user-mode-linux-devel-bounces@lists.sourceforge.net Subject: Re: [uml-devel] [PATCH] um: pass siginfo to guest process To: Richard Weinberger Cc: "user-mode-linux-devel@lists.sourceforge.net" On 06/08/2012 01:07 AM, Richard Weinberger wrote: > Am 07.06.2012 23:39, schrieb Martin P=E4rtel: >> On 06/08/2012 12:26 AM, Richard Weinberger wrote: >> >>> Am 07.06.2012 22:59, schrieb Martin P=E4rtel: >>>> Signal handlers in UML guest processes now get correct siginfo_t fields >>>> for SIGTRAP, SIGFPE, SIGILL and SIGBUS. Specifically, si_addr and si_c= ode >>>> are now correct where previously they were si_addr =3D NULL and si_cod= e =3D 128. >>> >>> What exactly is broken? >>> In my SIGSEGV test case si_addr is not NULL, it contains the correct fa= ulting address. >>> >> >> >> SIGSEGV is probably fine. At least SIGFPE is not. Test program below. >> >>>> + >>>> + ptrace(PTRACE_GETSIGINFO, pid, 0,&si); >>>> + >>> >>> Doesn't this leak the host siginfo_t into the guest? >>> >> >> >> Docs for PTRACE_GETSIGINFO say `si' gets a copy. After that, `si' is not= used for anything other than giving it to the guest. But I really can't sa= y I >> understand the surrounding code too well so please review carefully :) > > I was not talking about a memory leak. > What I meant was a information leak. > Using the host siginfo_t a guest process may get it's UID, PID, memory lo= cation, etc... on the host side. > Oh, darn, indeed. Well, getting si_code right fixed my immediate = problem, but I might look at this again some time next week unless = you've fixed it yourself by then. Thanks! ---------------------------------------------------------------------------= --- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and = threat landscape has changed and how IT managers can respond. Discussions = will include endpoint security, mobile security and the latest in malware = threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel