Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756660AbcJZAUO (ORCPT ); Tue, 25 Oct 2016 20:20:14 -0400 Received: from sub5.mail.dreamhost.com ([208.113.200.129]:50422 "EHLO homiemail-a79.g.dreamhost.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753364AbcJZAUM (ORCPT ); Tue, 25 Oct 2016 20:20:12 -0400 Date: Tue, 25 Oct 2016 17:20:10 -0700 From: Krister Johansen To: Arnaldo Carvalho de Melo Cc: Namhyung Kim , Masami Hiramatsu , =?utf-8?B?RnLDqWTDqXJpYw==?= Weisbecker , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 perf/core] perf script: fix a use after free crash. Message-ID: <20161026002010.GD2525@templeofstupid.com> References: <20161007022200.GB31113@sejong> <20161011092839.GC7837@templeofstupid.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161011092839.GC7837@templeofstupid.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 632 Lines: 15 On Tue, Oct 11, 2016 at 02:28:39AM -0700, Krister Johansen wrote: > If dso__load_kcore frees all of the existing maps, but one has already > been attached to a callchain cursor node, then we can get a SIGSEGV in > any function that happens to try to use this invalid cursor. Use the > existing map refcount mechanism to forestall cleanup of a map until the > cursor iterates past the node. It has been a couple of weeks since I sent out v2 of this patch. I understand that folks here have plenty of irons in the fire, but I wanted to double-check that nobody was waiting on me for additional information or changes. Thanks, -K