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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 EBD3BC433E6 for ; Tue, 16 Mar 2021 08:33:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B5D8264FF9 for ; Tue, 16 Mar 2021 08:33:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234923AbhCPIcv (ORCPT ); Tue, 16 Mar 2021 04:32:51 -0400 Received: from pegase1.c-s.fr ([93.17.236.30]:49887 "EHLO pegase1.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234888AbhCPIcm (ORCPT ); Tue, 16 Mar 2021 04:32:42 -0400 Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 4F063n3w10z9v02D; Tue, 16 Mar 2021 09:32:37 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id l5wHRkQBPkSS; Tue, 16 Mar 2021 09:32:37 +0100 (CET) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 4F063n0rlPz9v02C; Tue, 16 Mar 2021 09:32:37 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id E4E128B789; Tue, 16 Mar 2021 09:32:37 +0100 (CET) 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 jhvqrq-uzdBC; Tue, 16 Mar 2021 09:32:37 +0100 (CET) Received: from [192.168.4.90] (unknown [192.168.4.90]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 3ADBD8B782; Tue, 16 Mar 2021 09:32:37 +0100 (CET) Subject: Re: [PATCH mm] kfence: fix printk format for ptrdiff_t To: Alexander Potapenko , Marco Elver , Segher Boessenkool Cc: Andrew Morton , Dmitriy Vyukov , Andrey Konovalov , Jann Horn , LKML , Linux Memory Management List , kasan-dev References: <20210303121157.3430807-1-elver@google.com> From: Christophe Leroy Message-ID: Date: Tue, 16 Mar 2021 09:32:32 +0100 User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.8.0 MIME-Version: 1.0 In-Reply-To: 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 +segher Le 03/03/2021 à 13:27, Alexander Potapenko a écrit : > On Wed, Mar 3, 2021 at 1:12 PM Marco Elver wrote: >> >> Use %td for ptrdiff_t. >> >> Link: https://lkml.kernel.org/r/3abbe4c9-16ad-c168-a90f-087978ccd8f7@csgroup.eu >> Reported-by: Christophe Leroy >> Signed-off-by: Marco Elver > Reviewed-by: Alexander Potapenko > Still a problem. I don't understand, gcc bug ? The offending argument is 'const ptrdiff_t object_index' We have: arch/powerpc/include/uapi/asm/posix_types.h:typedef long __kernel_ptrdiff_t; include/linux/types.h:typedef __kernel_ptrdiff_t ptrdiff_t; And get: CC mm/kfence/report.o In file included from ./include/linux/printk.h:7, from ./include/linux/kernel.h:16, from mm/kfence/report.c:10: mm/kfence/report.c: In function 'kfence_report_error': ./include/linux/kern_levels.h:5:18: warning: format '%td' expects argument of type 'ptrdiff_t', but argument 6 has type 'long int' [-Wformat=] 5 | #define KERN_SOH "\001" /* ASCII Start Of Header */ | ^~~~~~ ./include/linux/kern_levels.h:11:18: note: in expansion of macro 'KERN_SOH' 11 | #define KERN_ERR KERN_SOH "3" /* error conditions */ | ^~~~~~~~ ./include/linux/printk.h:343:9: note: in expansion of macro 'KERN_ERR' 343 | printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__) | ^~~~~~~~ mm/kfence/report.c:213:3: note: in expansion of macro 'pr_err' 213 | pr_err("Out-of-bounds %s at 0x%p (%luB %s of kfence-#%td):\n", | ^~~~~~ ./include/linux/kern_levels.h:5:18: warning: format '%td' expects argument of type 'ptrdiff_t', but argument 4 has type 'long int' [-Wformat=] 5 | #define KERN_SOH "\001" /* ASCII Start Of Header */ | ^~~~~~ ./include/linux/kern_levels.h:11:18: note: in expansion of macro 'KERN_SOH' 11 | #define KERN_ERR KERN_SOH "3" /* error conditions */ | ^~~~~~~~ ./include/linux/printk.h:343:9: note: in expansion of macro 'KERN_ERR' 343 | printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__) | ^~~~~~~~ mm/kfence/report.c:222:3: note: in expansion of macro 'pr_err' 222 | pr_err("Use-after-free %s at 0x%p (in kfence-#%td):\n", | ^~~~~~ ./include/linux/kern_levels.h:5:18: warning: format '%td' expects argument of type 'ptrdiff_t', but argument 2 has type 'long int' [-Wformat=] 5 | #define KERN_SOH "\001" /* ASCII Start Of Header */ | ^~~~~~ ./include/linux/kern_levels.h:24:19: note: in expansion of macro 'KERN_SOH' 24 | #define KERN_CONT KERN_SOH "c" | ^~~~~~~~ ./include/linux/printk.h:385:9: note: in expansion of macro 'KERN_CONT' 385 | printk(KERN_CONT fmt, ##__VA_ARGS__) | ^~~~~~~~~ mm/kfence/report.c:229:3: note: in expansion of macro 'pr_cont' 229 | pr_cont(" (in kfence-#%td):\n", object_index); | ^~~~~~~ ./include/linux/kern_levels.h:5:18: warning: format '%td' expects argument of type 'ptrdiff_t', but argument 3 has type 'long int' [-Wformat=] 5 | #define KERN_SOH "\001" /* ASCII Start Of Header */ | ^~~~~~ ./include/linux/kern_levels.h:11:18: note: in expansion of macro 'KERN_SOH' 11 | #define KERN_ERR KERN_SOH "3" /* error conditions */ | ^~~~~~~~ ./include/linux/printk.h:343:9: note: in expansion of macro 'KERN_ERR' 343 | printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__) | ^~~~~~~~ mm/kfence/report.c:239:3: note: in expansion of macro 'pr_err' 239 | pr_err("Invalid free of 0x%p (in kfence-#%td):\n", (void *)address, | ^~~~~~ Christophe