From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp.polymtl.ca (smtp.polymtl.ca [132.207.4.11]) by sourceware.org (Postfix) with ESMTPS id AF3C5386FC03 for ; Fri, 14 May 2021 19:52:51 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org AF3C5386FC03 Received: from simark.ca (simark.ca [158.69.221.121]) (authenticated bits=0) by smtp.polymtl.ca (8.14.7/8.14.7) with ESMTP id 14EJqk1T024458 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 14 May 2021 15:52:50 -0400 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp.polymtl.ca 14EJqk1T024458 Received: from [10.0.0.11] (192-222-157-6.qc.cable.ebox.net [192.222.157.6]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPSA id 2943C1E01F; Fri, 14 May 2021 15:52:46 -0400 (EDT) Subject: Re: Trace/breakpoint trap. To: Jason Long , Eli Zaretskii via Gdb References: <895597245.1533806.1619862429301.ref@mail.yahoo.com> <895597245.1533806.1619862429301@mail.yahoo.com> <79240173-07cd-7ac1-b080-450efbb444b1@polymtl.ca> <2058203102.408071.1621021556704@mail.yahoo.com> From: Simon Marchi Message-ID: <30782f24-62b0-97c8-db48-d798e773fa53@polymtl.ca> Date: Fri, 14 May 2021 15:52:45 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: <2058203102.408071.1621021556704@mail.yahoo.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Poly-FromMTA: (simark.ca [158.69.221.121]) at Fri, 14 May 2021 19:52:46 +0000 X-Spam-Status: No, score=-4.1 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, NICE_REPLY_A, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_PASS, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gdb@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 14 May 2021 19:52:53 -0000 On 2021-05-14 3:45 p.m., Jason Long wrote:> Hello, > Thank you. > The "bt" show me: > > (gdb) bt > #0 0x000055555a7556f3 in ?? () > #1 0x00005555590002e0 in ?? () > #2 0x000055555a75474c in ?? () > #3 0x000055555a75a4a1 in ?? () > #4 0x0000555558fffb7c in ?? () > #5 0x000055555a75addb in ?? () > #6 0x0000555558ffe191 in ?? () > #7 0x000055555742527b in ?? () > #8 0x00007ffff568509b in __libc_start_main (main=0x555557425130, argc=1, > argv=0x7fffffffe288, init=, fini=, > rtld_fini=, stack_end=0x7fffffffe278) > at ../csu/libc-start.c:308 > #9 0x000055555742502a in _start () > > > And "info target" showed me: https://pastebin.ubuntu.com/p/3qT9yhkW3Y/ That tells you you are stopped somewhere in your "atomic" binary, whose .text section is at: 0x0000555557425000 - 0x000055555c440280 is .text It could be useful to have function names, for that you'll need a build with debug information (or install separate debug information, if available). You could try looking at the disassembly just around where you are stopped, see if it looks like an instruction that could have caused a trap, like a breakpoint instruction or a call to the "kill" syscall. It's also possible that this application uses SIGTRAP for its own purpose. For example, there could be multiple threads sending SIGTRAPs to each other. It's also possible that it's an anti-debugging technique. Simon