From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id 9FCC53857C5D for ; Fri, 22 Jul 2022 11:38:09 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 9FCC53857C5D Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-259-BhaKBLucOW2m37BXVVKdjg-1; Fri, 22 Jul 2022 07:38:06 -0400 X-MC-Unique: BhaKBLucOW2m37BXVVKdjg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id BFAA138005E5; Fri, 22 Jul 2022 11:38:05 +0000 (UTC) Received: from oldenburg.str.redhat.com (unknown [10.39.192.94]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2D53C1415118; Fri, 22 Jul 2022 11:38:05 +0000 (UTC) From: Florian Weimer To: Adhemerval Zanella Netto Cc: libc-alpha@sourceware.org Subject: Re: [PATCH] malloc: Simplify implementation of __malloc_assert References: <87a6924uvf.fsf@oldenburg.str.redhat.com> <21e64150-606d-df60-e50f-df09ca5a67ff@linaro.org> <87ilnq38cs.fsf@oldenburg.str.redhat.com> <67d80a43-c65a-b9db-af46-c73562e6c5b2@linaro.org> Date: Fri, 22 Jul 2022 13:38:03 +0200 In-Reply-To: <67d80a43-c65a-b9db-af46-c73562e6c5b2@linaro.org> (Adhemerval Zanella Netto's message of "Thu, 21 Jul 2022 10:40:11 -0300") Message-ID: <871qudfkdg.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.85 on 10.11.54.7 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain X-Spam-Status: No, score=-5.9 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_DNSWL_LOW, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 22 Jul 2022 11:38:10 -0000 * Adhemerval Zanella Netto: >> I think we converted almost all asserts that are reachable through heap >> corruption into malloc_printerr a couple of years ago, so the diagnostic >> value of the line number will be really low. That's why I had to resort >> to GDB to test this. >> >> Do you insist that I add file and line number information? > > I think it should be ok, what bothers me is we need to reimplement the > assert macro for malloc usage. It occurred to me that we do not need to use stderr for internal assert calls. We can use a different implementation based on __libc_message. Then the malloc code does not need its own version anymore. We can also change __libc_message to make it non-catchable (in process), and reset SIGABRT to SIG_DFL earlier. But maybe the last step goes too far. Thanks, Florian