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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8DCB1C433EF for ; Fri, 25 Feb 2022 04:28:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235620AbiBYE3R (ORCPT ); Thu, 24 Feb 2022 23:29:17 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57364 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229702AbiBYE3O (ORCPT ); Thu, 24 Feb 2022 23:29:14 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7D6CA1AAA77; Thu, 24 Feb 2022 20:28:43 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 00B44B82AC2; Fri, 25 Feb 2022 04:28:42 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 905E7C340E8; Fri, 25 Feb 2022 04:28:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1645763320; bh=7SThN/utKX/p0lzUCmG6ocQvEAx3lLFOHF56GsXqmkg=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=QDYtR8NlrGKuoQjmYA8kyhZOE9M5T1r29vrwrzKtqeW8ZEboLFyE9tpTLIHZrIsc2 nruqaf44dOGvL9m0YF8yy/0GnP7bjsDnUbUqIRzmMJPfXE0DXeAhxVhfed4IaeshxM 3dBB3rRybvVICiYVW2EwE6UiyRp2P0hHIB0n0MePLyot8SwYrU2i+wAnXsNlJLOQZg JdbB1DfWOrhGY/Jb/JrlNhbdzjO74CuLFiFEukShPqlCb0VjpFFv/dEFsnilhkTnnf /2HYT2lkEsKGxWybS9oRJ8pGnuvkqQGXNVQBnHCXm5s98tF2QqOVujOWC0O/sTxEOf zPy8zKCde1DGg== Message-ID: Date: Thu, 24 Feb 2022 22:28:32 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Subject: Re: [PATCH v2 02/18] uaccess: fix nios2 and microblaze get_user_8() Content-Language: en-US To: Arnd Bergmann , Linus Torvalds , Christoph Hellwig , linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-api@vger.kernel.org, arnd@arndb.de, linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk Cc: linux@armlinux.org.uk, will@kernel.org, guoren@kernel.org, bcain@codeaurora.org, geert@linux-m68k.org, monstr@monstr.eu, tsbogend@alpha.franken.de, nickhu@andestech.com, green.hu@gmail.com, shorne@gmail.com, deller@gmx.de, mpe@ellerman.id.au, peterz@infradead.org, mingo@redhat.com, mark.rutland@arm.com, hca@linux.ibm.com, dalias@libc.org, davem@davemloft.net, richard@nod.at, x86@kernel.org, jcmvbkbc@gmail.com, ebiederm@xmission.com, akpm@linux-foundation.org, ardb@kernel.org, linux-alpha@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, openrisc@lists.librecores.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, linux-xtensa@linux-xtensa.org References: <20220216131332.1489939-1-arnd@kernel.org> <20220216131332.1489939-3-arnd@kernel.org> From: Dinh Nguyen In-Reply-To: <20220216131332.1489939-3-arnd@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org On 2/16/22 07:13, Arnd Bergmann wrote: > From: Arnd Bergmann > > These two architectures implement 8-byte get_user() through > a memcpy() into a four-byte variable, which won't fit. > > Use a temporary 64-bit variable instead here, and use a double > cast the way that risc-v and openrisc do to avoid compile-time > warnings. > > Fixes: 6a090e97972d ("arch/microblaze: support get_user() of size 8 bytes") > Fixes: 5ccc6af5e88e ("nios2: Memory management") > Signed-off-by: Arnd Bergmann > --- > arch/microblaze/include/asm/uaccess.h | 18 +++++++++--------- > arch/nios2/include/asm/uaccess.h | 26 ++++++++++++++++---------- > 2 files changed, 25 insertions(+), 19 deletions(-) > > diff --git a/arch/microblaze/include/asm/uaccess.h b/arch/microblaze/include/asm/uaccess.h > index 5b6e0e7788f4..3fe96979d2c6 100644 > --- a/arch/microblaze/include/asm/uaccess.h > +++ b/arch/microblaze/include/asm/uaccess.h > @@ -130,27 +130,27 @@ extern long __user_bad(void); > > #define __get_user(x, ptr) \ > ({ \ > - unsigned long __gu_val = 0; \ > long __gu_err; \ > switch (sizeof(*(ptr))) { \ > case 1: \ > - __get_user_asm("lbu", (ptr), __gu_val, __gu_err); \ > + __get_user_asm("lbu", (ptr), x, __gu_err); \ > break; \ > case 2: \ > - __get_user_asm("lhu", (ptr), __gu_val, __gu_err); \ > + __get_user_asm("lhu", (ptr), x, __gu_err); \ > break; \ > case 4: \ > - __get_user_asm("lw", (ptr), __gu_val, __gu_err); \ > + __get_user_asm("lw", (ptr), x, __gu_err); \ > break; \ > - case 8: \ > - __gu_err = __copy_from_user(&__gu_val, ptr, 8); \ > - if (__gu_err) \ > - __gu_err = -EFAULT; \ > + case 8: { \ > + __u64 __x = 0; \ > + __gu_err = raw_copy_from_user(&__x, ptr, 8) ? \ > + -EFAULT : 0; \ > + (x) = (typeof(x))(typeof((x) - (x)))__x; \ > break; \ > + } \ > default: \ > /* __gu_val = 0; __gu_err = -EINVAL;*/ __gu_err = __user_bad();\ > } \ > - x = (__force __typeof__(*(ptr))) __gu_val; \ > __gu_err; \ > }) > > diff --git a/arch/nios2/include/asm/uaccess.h b/arch/nios2/include/asm/uaccess.h > index ba9340e96fd4..ca9285a915ef 100644 > --- a/arch/nios2/include/asm/uaccess.h > +++ b/arch/nios2/include/asm/uaccess.h > @@ -88,6 +88,7 @@ extern __must_check long strnlen_user(const char __user *s, long n); > /* Optimized macros */ > #define __get_user_asm(val, insn, addr, err) \ > { \ > + unsigned long __gu_val; \ > __asm__ __volatile__( \ > " movi %0, %3\n" \ > "1: " insn " %1, 0(%2)\n" \ > @@ -96,14 +97,20 @@ extern __must_check long strnlen_user(const char __user *s, long n); > " .section __ex_table,\"a\"\n" \ > " .word 1b, 2b\n" \ > " .previous" \ > - : "=&r" (err), "=r" (val) \ > + : "=&r" (err), "=r" (__gu_val) \ > : "r" (addr), "i" (-EFAULT)); \ > + val = (__force __typeof__(*(addr)))__gu_val; \ > } > > -#define __get_user_unknown(val, size, ptr, err) do { \ > +extern void __get_user_unknown(void); > + > +#define __get_user_8(val, ptr, err) do { \ > + u64 __val = 0; \ > err = 0; \ > - if (__copy_from_user(&(val), ptr, size)) { \ > + if (raw_copy_from_user(&(__val), ptr, sizeof(val))) { \ > err = -EFAULT; \ > + } else { \ > + val = (typeof(val))(typeof((val) - (val)))__val; \ > } \ > } while (0) > > @@ -119,8 +126,11 @@ do { \ > case 4: \ > __get_user_asm(val, "ldw", ptr, err); \ > break; \ > + case 8: \ > + __get_user_8(val, ptr, err); \ > + break; \ > default: \ > - __get_user_unknown(val, size, ptr, err); \ > + __get_user_unknown(); \ > break; \ > } \ > } while (0) > @@ -129,9 +139,7 @@ do { \ > ({ \ > long __gu_err = -EFAULT; \ > const __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \ > - unsigned long __gu_val = 0; \ > - __get_user_common(__gu_val, sizeof(*(ptr)), __gu_ptr, __gu_err);\ > - (x) = (__force __typeof__(x))__gu_val; \ > + __get_user_common(x, sizeof(*(ptr)), __gu_ptr, __gu_err); \ > __gu_err; \ > }) > > @@ -139,11 +147,9 @@ do { \ > ({ \ > long __gu_err = -EFAULT; \ > const __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \ > - unsigned long __gu_val = 0; \ > if (access_ok( __gu_ptr, sizeof(*__gu_ptr))) \ > - __get_user_common(__gu_val, sizeof(*__gu_ptr), \ > + __get_user_common(x, sizeof(*__gu_ptr), \ > __gu_ptr, __gu_err); \ > - (x) = (__force __typeof__(x))__gu_val; \ > __gu_err; \ > }) > Acked-by: Dinh Nguyen