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=-9.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED,USER_AGENT_GIT 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 58037C28CC1 for ; Thu, 30 May 2019 03:35:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3016D24B47 for ; Thu, 30 May 2019 03:35:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559187300; bh=ktULjbtGiu6USQiIsLXH9WoJV2uliWLQyEHGbCjaLcs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=A/YNTWhsVv9mWEbPluRTdPMOQ8w7XqQnOqa+sHrLuk0EJ6euLaKEHykIQiY3suDPP jqCTmLg2wySOMRhUMVAX8ffAL/iYyNpY/GrAEP+akFS5kFHec2kWFdlsNmqV5VdbbU p6YHQ6fTQNecaUk2vFZq4GFevxdpgw+UFME+91z0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387820AbfE3D1C (ORCPT ); Wed, 29 May 2019 23:27:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:53900 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730890AbfE3DTI (ORCPT ); Wed, 29 May 2019 23:19:08 -0400 Received: from localhost (ip67-88-213-2.z213-88-67.customer.algx.net [67.88.213.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 65F602474A; Thu, 30 May 2019 03:19:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559186347; bh=ktULjbtGiu6USQiIsLXH9WoJV2uliWLQyEHGbCjaLcs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xRReyaqO62nHMc1l6UcizGOGusMwC5uTv7PD9ZYLPKBbno/2ltdmmcWRmlZa6dtyV 0snfoWEtGGQBMycQPfmqe4cI5oS1WQvMkyJElw+OpBTe/bdw0k4cYSzhrJLIdUB7I0 OcsS4xbLWauETMrShMJBzqLpSjoPd4bZ5OQ0Kpjk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Randy Dunlap , "Peter Zijlstra (Intel)" , Linus Torvalds , Thomas Gleixner , luto@kernel.org, Ingo Molnar , Sasha Levin Subject: [PATCH 4.14 082/193] mm/uaccess: Use unsigned long to placate UBSAN warnings on older GCC versions Date: Wed, 29 May 2019 20:05:36 -0700 Message-Id: <20190530030500.276161260@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190530030446.953835040@linuxfoundation.org> References: <20190530030446.953835040@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit 29da93fea3ea39ab9b12270cc6be1b70ef201c9e ] Randy reported objtool triggered on his (GCC-7.4) build: lib/strncpy_from_user.o: warning: objtool: strncpy_from_user()+0x315: call to __ubsan_handle_add_overflow() with UACCESS enabled lib/strnlen_user.o: warning: objtool: strnlen_user()+0x337: call to __ubsan_handle_sub_overflow() with UACCESS enabled This is due to UBSAN generating signed-overflow-UB warnings where it should not. Prior to GCC-8 UBSAN ignored -fwrapv (which the kernel uses through -fno-strict-overflow). Make the functions use 'unsigned long' throughout. Reported-by: Randy Dunlap Signed-off-by: Peter Zijlstra (Intel) Acked-by: Randy Dunlap # build-tested Acked-by: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: luto@kernel.org Link: http://lkml.kernel.org/r/20190424072208.754094071@infradead.org Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- lib/strncpy_from_user.c | 5 +++-- lib/strnlen_user.c | 4 ++-- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/lib/strncpy_from_user.c b/lib/strncpy_from_user.c index b53e1b5d80f42..e304b54c9c7dd 100644 --- a/lib/strncpy_from_user.c +++ b/lib/strncpy_from_user.c @@ -23,10 +23,11 @@ * hit it), 'max' is the address space maximum (and we return * -EFAULT if we hit it). */ -static inline long do_strncpy_from_user(char *dst, const char __user *src, long count, unsigned long max) +static inline long do_strncpy_from_user(char *dst, const char __user *src, + unsigned long count, unsigned long max) { const struct word_at_a_time constants = WORD_AT_A_TIME_CONSTANTS; - long res = 0; + unsigned long res = 0; /* * Truncate 'max' to the user-specified limit, so that diff --git a/lib/strnlen_user.c b/lib/strnlen_user.c index 60d0bbda8f5e5..184f80f7bacfa 100644 --- a/lib/strnlen_user.c +++ b/lib/strnlen_user.c @@ -28,7 +28,7 @@ static inline long do_strnlen_user(const char __user *src, unsigned long count, unsigned long max) { const struct word_at_a_time constants = WORD_AT_A_TIME_CONSTANTS; - long align, res = 0; + unsigned long align, res = 0; unsigned long c; /* @@ -42,7 +42,7 @@ static inline long do_strnlen_user(const char __user *src, unsigned long count, * Do everything aligned. But that means that we * need to also expand the maximum.. */ - align = (sizeof(long) - 1) & (unsigned long)src; + align = (sizeof(unsigned long) - 1) & (unsigned long)src; src -= align; max += align; -- 2.20.1