From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 117199 invoked by alias); 21 Dec 2015 16:53:16 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 117190 invoked by uid 89); 21 Dec 2015 16:53:15 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.4 required=5.0 tests=AWL,BAYES_00,KAM_LAZY_DOMAIN_SECURITY,RP_MATCHES_RCVD,SPF_HELO_PASS autolearn=no version=3.3.2 spammy= X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES256-GCM-SHA384 encrypted) ESMTPS; Mon, 21 Dec 2015 16:53:14 +0000 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (Postfix) with ESMTPS id 5D0B48F4F7; Mon, 21 Dec 2015 16:53:13 +0000 (UTC) Received: from [127.0.0.1] (ovpn01.gateway.prod.ext.phx2.redhat.com [10.5.9.1]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id tBLGrCrP005074; Mon, 21 Dec 2015 11:53:12 -0500 Message-ID: <56782E78.8070400@redhat.com> Date: Mon, 21 Dec 2015 16:53:00 -0000 From: Pedro Alves User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Joel Brobecker , gdb-patches@sourceware.org Subject: Re: [RFA] gdbserver crash in gdb/gdbserver/thread.c::thread_search_callback References: <1450710922-29601-1-git-send-email-brobecker@adacore.com> In-Reply-To: <1450710922-29601-1-git-send-email-brobecker@adacore.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-SW-Source: 2015-12/txt/msg00439.txt.bz2 On 12/21/2015 03:15 PM, Joel Brobecker wrote: > Connecting GDB to a LynxOS-178 GDBserver causes GDBserver to crash: > > % gdbserver :4444 simple_main > Process simple_main created; pid = 19 > Listening on port 4444 > Remote debugging from host 205.232.38.10 > Segmentation fault (core dumped) > > We saw this crash on LynxOS and also when using GDBserver on Windows. > > The crash happens in thread_search_callback where the function > calls the_target->thread_stopped (via the thread_stopped macro) > without verifying whether the callback is NULL or not. > > For the record, the regression was introduced by: > > commit a67a9faef0e32886c83611cc7a0ba61e91123063 > Date: Mon Nov 30 16:05:26 2015 +0000 > Subject: gdbserver:prepare_access_memory: pick another thread > Whoops, sorry about that. > gdb/gdbserver/ChangeLog: > > * target.c (thread_search_callback): Add check that > the thread_stopped target callback is not NULL before > calling it. > > Does the fix look good to you? > Tested on both Windows (native gdbserver) and LynxOS using > AdaCore's gdb-testsuite. LGTM. Thanks, Pedro Alves