From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-out.m-online.net (mail-out.m-online.net [IPv6:2001:a60:0:28:0:1:25:1]) by sourceware.org (Postfix) with ESMTPS id 000F7393D03B for ; Tue, 13 Apr 2021 10:51:27 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 000F7393D03B Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=linux-m68k.org Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=whitebox@nefkom.net Received: from frontend01.mail.m-online.net (unknown [192.168.8.182]) by mail-out.m-online.net (Postfix) with ESMTP id 4FKMq31cLGz1s4ct; Tue, 13 Apr 2021 12:51:27 +0200 (CEST) Received: from localhost (dynscan1.mnet-online.de [192.168.6.70]) by mail.m-online.net (Postfix) with ESMTP id 4FKMq31Hmfz1sP6T; Tue, 13 Apr 2021 12:51:27 +0200 (CEST) X-Virus-Scanned: amavisd-new at mnet-online.de Received: from mail.mnet-online.de ([192.168.8.182]) by localhost (dynscan1.mail.m-online.net [192.168.6.70]) (amavisd-new, port 10024) with ESMTP id 2nmPuvTNg7FT; Tue, 13 Apr 2021 12:51:26 +0200 (CEST) X-Auth-Info: T4WM/awVXBvoW3eWDBkyNAk2LT2Qp/+SydBUkV80MIpm63vBm6i/Q8DFThMTNBIk Received: from igel.home (ppp-46-244-161-206.dynamic.mnet-online.de [46.244.161.206]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.mnet-online.de (Postfix) with ESMTPSA; Tue, 13 Apr 2021 12:51:26 +0200 (CEST) Received: by igel.home (Postfix, from userid 1000) id C204A2C36B4; Tue, 13 Apr 2021 12:51:25 +0200 (CEST) From: Andreas Schwab To: Szabolcs Nagy Cc: Szabolcs Nagy via Libc-alpha Subject: Re: [PATCH v2 01/14] elf: Fix a DTV setup issue [BZ #27136] References: <87r1jeh98l.fsf@igel.home> <20210413093538.GU23289@arm.com> <87mtu2h4c6.fsf@igel.home> <20210413103450.GW23289@arm.com> X-Yow: Imagine--a WORLD without POODLES... Date: Tue, 13 Apr 2021 12:51:25 +0200 In-Reply-To: <20210413103450.GW23289@arm.com> (Szabolcs Nagy's message of "Tue, 13 Apr 2021 11:34:50 +0100") Message-ID: <87blaih2z6.fsf@igel.home> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Spam-Status: No, score=-2.8 required=5.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, KAM_DMARC_STATUS, RCVD_IN_DNSWL_LOW, SPF_HELO_NONE, 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: 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: Tue, 13 Apr 2021 10:51:29 -0000 On Apr 13 2021, Szabolcs Nagy wrote: > The 04/13/2021 12:22, Andreas Schwab wrote: >> On Apr 13 2021, Szabolcs Nagy wrote: >> >> > The 04/13/2021 10:36, Andreas Schwab wrote: >> >> On Apr 13 2021, Szabolcs Nagy via Libc-alpha wrote: >> >> >> >> > The max modid is a valid index in the dtv, it should not be skipped. >> >> >> >> Does this check in _dl_allocate_tls_init need to be adjusted as well? >> >> >> >> /* Check if the current dtv is big enough. */ >> >> if (dtv[-1].counter < GL(dl_tls_max_dtv_idx)) >> > >> > no, that seems fine because counter is not the dtv length but >> > the maximum valid index (dtv[dtv[-1].counter] is valid, the >> > dtv array size is counter+2 to accomodate for dtv[-1] and [0]) >> >> Since both dtv[-1].counter and GL(dl_tls_max_dtv_idx) are indexes, not >> lengths, I would expect them to be compared with <=. > > but the code is > > /* Check if the current dtv is big enough. */ > if (dtv[-1].counter < GL(dl_tls_max_dtv_idx)) > { > /* Resize the dtv. */ > dtv = _dl_resize_dtv (dtv, GL(dl_tls_max_dtv_idx)); > > in case of == there is no need to resize: the dtv array is > large enough for the observed GL(dl_tls_max_dtv_idx). I think it would be easier to understand if the condition would be written as (GL(dl_tls_max_dtv_idx) > dtv[-1].counter). Andreas. -- Andreas Schwab, schwab@linux-m68k.org GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1 "And now for something completely different."