From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E4E39C433B4 for ; Tue, 11 May 2021 04:54:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B0C2A61554 for ; Tue, 11 May 2021 04:54:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230016AbhEKEzW (ORCPT ); Tue, 11 May 2021 00:55:22 -0400 Received: from pegase2.c-s.fr ([93.17.235.10]:49725 "EHLO pegase2.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229885AbhEKEzV (ORCPT ); Tue, 11 May 2021 00:55:21 -0400 Received: from localhost (mailhub3.si.c-s.fr [172.26.127.67]) by localhost (Postfix) with ESMTP id 4FfQYx566Pz9sdc; Tue, 11 May 2021 06:54:13 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from pegase2.c-s.fr ([172.26.127.65]) by localhost (pegase2.c-s.fr [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id nHqyZRKRWhrq; Tue, 11 May 2021 06:54:13 +0200 (CEST) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase2.c-s.fr (Postfix) with ESMTP id 4FfQYx48Qgz9sdb; Tue, 11 May 2021 06:54:13 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 6C0208B79E; Tue, 11 May 2021 06:54:13 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id rTdXQYM9Q2Zd; Tue, 11 May 2021 06:54:13 +0200 (CEST) Received: from [192.168.4.90] (unknown [192.168.4.90]) by messagerie.si.c-s.fr (Postfix) with ESMTP id E958C8B766; Tue, 11 May 2021 06:54:12 +0200 (CEST) Subject: Re: [PATCH] powerpc/legacy_serial: Fix UBSAN: array-index-out-of-bounds To: Michael Ellerman , Segher Boessenkool Cc: Benjamin Herrenschmidt , Paul Mackerras , pmenzel@molgen.mpg.de, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org References: <20210510211444.GE10366@gate.crashing.org> <87sg2uxe7h.fsf@mpe.ellerman.id.au> From: Christophe Leroy Message-ID: Date: Tue, 11 May 2021 06:54:14 +0200 User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: <87sg2uxe7h.fsf@mpe.ellerman.id.au> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: fr Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le 11/05/2021 à 03:16, Michael Ellerman a écrit : > Segher Boessenkool writes: > >> On Sat, May 08, 2021 at 06:36:21AM +0000, Christophe Leroy wrote: >>> UBSAN complains when a pointer is calculated with invalid >>> 'legacy_serial_console' index, allthough the index is verified >>> before dereferencing the pointer. >> >> Addressing like this is UB already. >> >> You could just move this: >> >>> - if (legacy_serial_console < 0) >>> - return 0; >> >> to before >> >>> - struct legacy_serial_info *info = &legacy_serial_infos[legacy_serial_console]; >>> - struct plat_serial8250_port *port = &legacy_serial_ports[legacy_serial_console]; >> >> and no other change is necessary. > > Yeah I sent a v2 doing that, thanks. > I wanted something looking similar to setup_legacy_serial_console(), but of course this also works. Christophe From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0CC8DC433B4 for ; Tue, 11 May 2021 04:54:47 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 377D961554 for ; Tue, 11 May 2021 04:54:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 377D961554 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=csgroup.eu Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4FfQZX5kMfz307n for ; Tue, 11 May 2021 14:54:44 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=csgroup.eu (client-ip=93.17.235.10; helo=pegase2.c-s.fr; envelope-from=christophe.leroy@csgroup.eu; receiver=) Received: from pegase2.c-s.fr (pegase2.c-s.fr [93.17.235.10]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4FfQZ65BJ6z2yQw for ; Tue, 11 May 2021 14:54:19 +1000 (AEST) Received: from localhost (mailhub3.si.c-s.fr [172.26.127.67]) by localhost (Postfix) with ESMTP id 4FfQYx566Pz9sdc; Tue, 11 May 2021 06:54:13 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from pegase2.c-s.fr ([172.26.127.65]) by localhost (pegase2.c-s.fr [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id nHqyZRKRWhrq; Tue, 11 May 2021 06:54:13 +0200 (CEST) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase2.c-s.fr (Postfix) with ESMTP id 4FfQYx48Qgz9sdb; Tue, 11 May 2021 06:54:13 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 6C0208B79E; Tue, 11 May 2021 06:54:13 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id rTdXQYM9Q2Zd; Tue, 11 May 2021 06:54:13 +0200 (CEST) Received: from [192.168.4.90] (unknown [192.168.4.90]) by messagerie.si.c-s.fr (Postfix) with ESMTP id E958C8B766; Tue, 11 May 2021 06:54:12 +0200 (CEST) Subject: Re: [PATCH] powerpc/legacy_serial: Fix UBSAN: array-index-out-of-bounds To: Michael Ellerman , Segher Boessenkool References: <20210510211444.GE10366@gate.crashing.org> <87sg2uxe7h.fsf@mpe.ellerman.id.au> From: Christophe Leroy Message-ID: Date: Tue, 11 May 2021 06:54:14 +0200 User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: <87sg2uxe7h.fsf@mpe.ellerman.id.au> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: fr Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paul Mackerras , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, pmenzel@molgen.mpg.de Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Le 11/05/2021 à 03:16, Michael Ellerman a écrit : > Segher Boessenkool writes: > >> On Sat, May 08, 2021 at 06:36:21AM +0000, Christophe Leroy wrote: >>> UBSAN complains when a pointer is calculated with invalid >>> 'legacy_serial_console' index, allthough the index is verified >>> before dereferencing the pointer. >> >> Addressing like this is UB already. >> >> You could just move this: >> >>> - if (legacy_serial_console < 0) >>> - return 0; >> >> to before >> >>> - struct legacy_serial_info *info = &legacy_serial_infos[legacy_serial_console]; >>> - struct plat_serial8250_port *port = &legacy_serial_ports[legacy_serial_console]; >> >> and no other change is necessary. > > Yeah I sent a v2 doing that, thanks. > I wanted something looking similar to setup_legacy_serial_console(), but of course this also works. Christophe