From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934331Ab3JPMrl (ORCPT ); Wed, 16 Oct 2013 08:47:41 -0400 Received: from e39.co.us.ibm.com ([32.97.110.160]:42335 "EHLO e39.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932406Ab3JPMrk (ORCPT ); Wed, 16 Oct 2013 08:47:40 -0400 Date: Wed, 16 Oct 2013 18:17:33 +0530 From: Srikar Dronamraju To: Oleg Nesterov Cc: Ingo Molnar , Anton Arapov , David Smith , "Frank Ch. Eigler" , Martin Cermak , Peter Zijlstra , linux-kernel@vger.kernel.org Subject: Re: [PATCH 4/5] uprobes: Change uprobe_copy_process() to dup return_instances Message-ID: <20131016124733.GG19729@linux.vnet.ibm.com> Reply-To: Srikar Dronamraju References: <20131013191815.GA32466@redhat.com> <20131013191841.GA32499@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <20131013191841.GA32499@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13101612-9332-0000-0000-000001CA505C Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Oleg Nesterov [2013-10-13 21:18:41]: > uprobe_copy_process() assumes that the new child doesn't need > ->utask, it should be allocated by demand. > > But this is not true if the forking task has the pending ret- > probes, the child should report them as well and thus it needs > the copy of parent's ->return_instances chain. Otherwise the > child crashes when it returns from the probed function. > > Note: this change alone doesn't fix the problem, see the next > change. > > Cc: stable@vger.kernel.org # 3.9+ > Reported-by: Martin Cermak > Reported-by: David Smith > Signed-off-by: Oleg Nesterov Acked-by: Srikar Dronamraju -- Thanks and Regards Srikar Dronamraju