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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 1A4E3C5517A for ; Fri, 30 Oct 2020 15:50:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BC0AA22245 for ; Fri, 30 Oct 2020 15:50:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604073005; bh=dw+FNOj9rldGYjGgvqnlK7d2jveyytjZONsX8DAT/q4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=KRzA2VSmyipXaHJAIt7EIFk1H3rtH4juLTWc/qzqV6IxA6HIDbYYUNXKGN6EbOqTG bSQiD/QTjoOQmDNQ/Xg76+dZcfPCP9cpyVGCEzm+tJUv/fe0O5ValLw+DlcD6yNLGW xHSmCV6VtArZqoVfM70Cino/+am9Ql+MUMNZNZvw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727291AbgJ3PuF (ORCPT ); Fri, 30 Oct 2020 11:50:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:42410 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727231AbgJ3Pts (ORCPT ); Fri, 30 Oct 2020 11:49:48 -0400 Received: from localhost.localdomain (HSI-KBW-46-223-126-90.hsi.kabel-badenwuerttemberg.de [46.223.126.90]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5308F22253; Fri, 30 Oct 2020 15:49:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604072986; bh=dw+FNOj9rldGYjGgvqnlK7d2jveyytjZONsX8DAT/q4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=R0a5HNrBIRQUBu6ig7nuv+MepNXNQ24+T16k0PcALBnQZR4OF92jeVXmuZSrRVNd6 XZ5W5D//tVylebaXnmmw2zHAt37AnRO8154mQwRo1xA0cfvtRiA++v20bomKsCI+V5 yyEMPB23AsmMXSFWEGc+XVUndufFs2TfKX+nvOUg= From: Arnd Bergmann To: Russell King , Christoph Hellwig Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, viro@zeniv.linux.org.uk, linus.walleij@linaro.org, arnd@arndb.de Subject: [PATCH 8/9] ARM: uaccess: add __{get,put}_kernel_nofault Date: Fri, 30 Oct 2020 16:49:18 +0100 Message-Id: <20201030154919.1246645-8-arnd@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201030154919.1246645-1-arnd@kernel.org> References: <20201030154519.1245983-1-arnd@kernel.org> <20201030154919.1246645-1-arnd@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arnd Bergmann These mimic the behavior of get_user and put_user, except for domain switching, address limit checking and handling of mismatched sizes, none of which are relevant here. To work with pre-Armv6 kernels, this has to avoid TUSER() inside of the new macros, the new approach passes the "t" string along with the opcode, which is a bit uglier but avoids duplicating more code. As there is no __get_user_asm_dword(), I work around it by copying 32 bit at a time, which is possible because the output size is known. Signed-off-by: Arnd Bergmann --- arch/arm/include/asm/uaccess.h | 123 ++++++++++++++++++++++----------- 1 file changed, 83 insertions(+), 40 deletions(-) diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h index a13d90206472..4f60638755c4 100644 --- a/arch/arm/include/asm/uaccess.h +++ b/arch/arm/include/asm/uaccess.h @@ -308,11 +308,11 @@ static inline void set_fs(mm_segment_t fs) #define __get_user(x, ptr) \ ({ \ long __gu_err = 0; \ - __get_user_err((x), (ptr), __gu_err); \ + __get_user_err((x), (ptr), __gu_err, TUSER()); \ __gu_err; \ }) -#define __get_user_err(x, ptr, err) \ +#define __get_user_err(x, ptr, err, __t) \ do { \ unsigned long __gu_addr = (unsigned long)(ptr); \ unsigned long __gu_val; \ @@ -321,18 +321,19 @@ do { \ might_fault(); \ __ua_flags = uaccess_save_and_enable(); \ switch (sizeof(*(ptr))) { \ - case 1: __get_user_asm_byte(__gu_val, __gu_addr, err); break; \ - case 2: __get_user_asm_half(__gu_val, __gu_addr, err); break; \ - case 4: __get_user_asm_word(__gu_val, __gu_addr, err); break; \ + case 1: __get_user_asm_byte(__gu_val, __gu_addr, err, __t); break; \ + case 2: __get_user_asm_half(__gu_val, __gu_addr, err, __t); break; \ + case 4: __get_user_asm_word(__gu_val, __gu_addr, err, __t); break; \ default: (__gu_val) = __get_user_bad(); \ } \ uaccess_restore(__ua_flags); \ (x) = (__typeof__(*(ptr)))__gu_val; \ } while (0) +#endif #define __get_user_asm(x, addr, err, instr) \ __asm__ __volatile__( \ - "1: " TUSER(instr) " %1, [%2], #0\n" \ + "1: " instr " %1, [%2], #0\n" \ "2:\n" \ " .pushsection .text.fixup,\"ax\"\n" \ " .align 2\n" \ @@ -348,40 +349,38 @@ do { \ : "r" (addr), "i" (-EFAULT) \ : "cc") -#define __get_user_asm_byte(x, addr, err) \ - __get_user_asm(x, addr, err, ldrb) +#define __get_user_asm_byte(x, addr, err, __t) \ + __get_user_asm(x, addr, err, "ldrb" __t) #if __LINUX_ARM_ARCH__ >= 6 -#define __get_user_asm_half(x, addr, err) \ - __get_user_asm(x, addr, err, ldrh) +#define __get_user_asm_half(x, addr, err, __t) \ + __get_user_asm(x, addr, err, "ldrh" __t) #else #ifndef __ARMEB__ -#define __get_user_asm_half(x, __gu_addr, err) \ +#define __get_user_asm_half(x, __gu_addr, err, __t) \ ({ \ unsigned long __b1, __b2; \ - __get_user_asm_byte(__b1, __gu_addr, err); \ - __get_user_asm_byte(__b2, __gu_addr + 1, err); \ + __get_user_asm_byte(__b1, __gu_addr, err, __t); \ + __get_user_asm_byte(__b2, __gu_addr + 1, err, __t); \ (x) = __b1 | (__b2 << 8); \ }) #else -#define __get_user_asm_half(x, __gu_addr, err) \ +#define __get_user_asm_half(x, __gu_addr, err, __t) \ ({ \ unsigned long __b1, __b2; \ - __get_user_asm_byte(__b1, __gu_addr, err); \ - __get_user_asm_byte(__b2, __gu_addr + 1, err); \ + __get_user_asm_byte(__b1, __gu_addr, err, __t); \ + __get_user_asm_byte(__b2, __gu_addr + 1, err, __t); \ (x) = (__b1 << 8) | __b2; \ }) #endif #endif /* __LINUX_ARM_ARCH__ >= 6 */ -#define __get_user_asm_word(x, addr, err) \ - __get_user_asm(x, addr, err, ldr) -#endif - +#define __get_user_asm_word(x, addr, err, __t) \ + __get_user_asm(x, addr, err, "ldr" __t) #define __put_user_switch(x, ptr, __err, __fn) \ do { \ @@ -425,7 +424,7 @@ do { \ #define __put_user_nocheck(x, __pu_ptr, __err, __size) \ do { \ unsigned long __pu_addr = (unsigned long)__pu_ptr; \ - __put_user_nocheck_##__size(x, __pu_addr, __err); \ + __put_user_nocheck_##__size(x, __pu_addr, __err, TUSER());\ } while (0) #define __put_user_nocheck_1 __put_user_asm_byte @@ -433,9 +432,11 @@ do { \ #define __put_user_nocheck_4 __put_user_asm_word #define __put_user_nocheck_8 __put_user_asm_dword +#endif /* !CONFIG_CPU_SPECTRE */ + #define __put_user_asm(x, __pu_addr, err, instr) \ __asm__ __volatile__( \ - "1: " TUSER(instr) " %1, [%2], #0\n" \ + "1: " instr " %1, [%2], #0\n" \ "2:\n" \ " .pushsection .text.fixup,\"ax\"\n" \ " .align 2\n" \ @@ -450,36 +451,36 @@ do { \ : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \ : "cc") -#define __put_user_asm_byte(x, __pu_addr, err) \ - __put_user_asm(x, __pu_addr, err, strb) +#define __put_user_asm_byte(x, __pu_addr, err, __t) \ + __put_user_asm(x, __pu_addr, err, "strb" __t) #if __LINUX_ARM_ARCH__ >= 6 -#define __put_user_asm_half(x, __pu_addr, err) \ - __put_user_asm(x, __pu_addr, err, strh) +#define __put_user_asm_half(x, __pu_addr, err, __t) \ + __put_user_asm(x, __pu_addr, err, "strh" __t) #else #ifndef __ARMEB__ -#define __put_user_asm_half(x, __pu_addr, err) \ +#define __put_user_asm_half(x, __pu_addr, err, __t) \ ({ \ unsigned long __temp = (__force unsigned long)(x); \ - __put_user_asm_byte(__temp, __pu_addr, err); \ - __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \ + __put_user_asm_byte(__temp, __pu_addr, err, __t); \ + __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err, __t);\ }) #else -#define __put_user_asm_half(x, __pu_addr, err) \ +#define __put_user_asm_half(x, __pu_addr, err, __t) \ ({ \ unsigned long __temp = (__force unsigned long)(x); \ - __put_user_asm_byte(__temp >> 8, __pu_addr, err); \ - __put_user_asm_byte(__temp, __pu_addr + 1, err); \ + __put_user_asm_byte(__temp >> 8, __pu_addr, err, __t); \ + __put_user_asm_byte(__temp, __pu_addr + 1, err, __t); \ }) #endif #endif /* __LINUX_ARM_ARCH__ >= 6 */ -#define __put_user_asm_word(x, __pu_addr, err) \ - __put_user_asm(x, __pu_addr, err, str) +#define __put_user_asm_word(x, __pu_addr, err, __t) \ + __put_user_asm(x, __pu_addr, err, "str" __t) #ifndef __ARMEB__ #define __reg_oper0 "%R2" @@ -489,12 +490,12 @@ do { \ #define __reg_oper1 "%R2" #endif -#define __put_user_asm_dword(x, __pu_addr, err) \ +#define __put_user_asm_dword(x, __pu_addr, err, __t) \ __asm__ __volatile__( \ - ARM( "1: " TUSER(str) " " __reg_oper1 ", [%1], #4\n" ) \ - ARM( "2: " TUSER(str) " " __reg_oper0 ", [%1]\n" ) \ - THUMB( "1: " TUSER(str) " " __reg_oper1 ", [%1]\n" ) \ - THUMB( "2: " TUSER(str) " " __reg_oper0 ", [%1, #4]\n" ) \ + ARM( "1: str" __t " " __reg_oper1 ", [%1], #4\n" ) \ + ARM( "2: str" __t " " __reg_oper0 ", [%1]\n" ) \ + THUMB( "1: str" __t " " __reg_oper1 ", [%1]\n" ) \ + THUMB( "2: str" __t " " __reg_oper0 ", [%1, #4]\n" ) \ "3:\n" \ " .pushsection .text.fixup,\"ax\"\n" \ " .align 2\n" \ @@ -510,7 +511,49 @@ do { \ : "r" (x), "i" (-EFAULT) \ : "cc") -#endif /* !CONFIG_CPU_SPECTRE */ +#define HAVE_GET_KERNEL_NOFAULT + +#define __get_kernel_nofault(dst, src, type, err_label) \ +do { \ + const type *__pk_ptr = (src); \ + unsigned long __src = (unsigned long)(__pk_ptr); \ + type __val; \ + int __err = 0; \ + switch (sizeof(type)) { \ + case 1: __get_user_asm_byte(__val, __src, __err, ""); break; \ + case 2: __get_user_asm_half(__val, __src, __err, ""); break; \ + case 4: __get_user_asm_word(__val, __src, __err, ""); break; \ + case 8: { \ + u32 *__v32 = (u32*)&__val; \ + __get_user_asm_word(__v32[0], __src, __err, ""); \ + if (__err) \ + break; \ + __get_user_asm_word(__v32[1], __src+4, __err, ""); \ + break; \ + } \ + default: __err = __get_user_bad(); break; \ + } \ + *(type *)(dst) = __val; \ + if (__err) \ + goto err_label; \ +} while (0) + +#define __put_kernel_nofault(dst, src, type, err_label) \ +do { \ + const type *__pk_ptr = (dst); \ + unsigned long __dst = (unsigned long)__pk_ptr; \ + int __err = 0; \ + type __val = *(type *)src; \ + switch (sizeof(type)) { \ + case 1: __put_user_asm_byte(__val, __dst, __err, ""); break; \ + case 2: __put_user_asm_half(__val, __dst, __err, ""); break; \ + case 4: __put_user_asm_word(__val, __dst, __err, ""); break; \ + case 8: __put_user_asm_dword(__val, __dst, __err, ""); break; \ + default: __err = __put_user_bad(); break; \ + } \ + if (__err) \ + goto err_label; \ +} while (0) #ifdef CONFIG_MMU extern unsigned long __must_check -- 2.27.0