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 26E8AC28CC0 for ; Thu, 30 May 2019 03:45:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F1F5724CA5 for ; Thu, 30 May 2019 03:45:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559187941; bh=qydilEWEQqasVCq9cYkBAWbqdN+AQcFoT0hQC5NMJ3g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=KSXjBrzgkGFkB3ionkSNwTlxHVkto1upCKkP/9Bwe1Fhc6TsHuYSLlX+qW9kRix/e fNTUV7eFvD6IXDJlKApMO+ZfxMv2MOxQhhvj6oMAru3COh4KRW+UUpYCQH5IeqomJt i4okHxIotPCWmLD3XJbztNleSH2z1jO4uPZq5t24= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732163AbfE3Dpj (ORCPT ); Wed, 29 May 2019 23:45:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:59924 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732322AbfE3DUr (ORCPT ); Wed, 29 May 2019 23:20:47 -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 DA5032496D; Thu, 30 May 2019 03:20:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559186445; bh=qydilEWEQqasVCq9cYkBAWbqdN+AQcFoT0hQC5NMJ3g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=POtrs3nm9ynx4f5GEUc6Y1cy1y6a1pUcxixIXTWKNzLklLRfXJQEj7b9xu5YQXubM 2rj+i3Q4LGeShFyXSeDBw8WkP46H880jR5JpEb2lxGwnoXINebYEKqG460tnAeAGnL +Kqt40YWBTuOaqR4O7Y+50HmXepbltKnH0cr55dI= 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 4.9 053/128] mm/uaccess: Use unsigned long to placate UBSAN warnings on older GCC versions Date: Wed, 29 May 2019 20:06:25 -0700 Message-Id: <20190530030444.261281524@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190530030432.977908967@linuxfoundation.org> References: <20190530030432.977908967@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@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 7e35fc450c5bb..5a07f19059c36 100644 --- a/lib/strncpy_from_user.c +++ b/lib/strncpy_from_user.c @@ -22,10 +22,11 @@ * 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 8e105ed4df12b..9ff4f3bbb1aae 100644 --- a/lib/strnlen_user.c +++ b/lib/strnlen_user.c @@ -27,7 +27,7 @@ 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; /* @@ -41,7 +41,7 @@ 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