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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 6578BC433EF for ; Thu, 16 Sep 2021 07:07:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3638461029 for ; Thu, 16 Sep 2021 07:07:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234539AbhIPHI4 (ORCPT ); Thu, 16 Sep 2021 03:08:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58656 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234532AbhIPHIz (ORCPT ); Thu, 16 Sep 2021 03:08:55 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EBE96C061574 for ; Thu, 16 Sep 2021 00:07:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=j8G0Qw1OqMPcWgsI54a+i3ZvID2rz/bU9IASzI7zYTw=; b=X4ysEW3QH+tcsL2bcXnH5F0XUI xw4tpFZaAFk6Bmp0W/hiUZM5TPTZaiLB1QkB/Q2Qq/dNQwT7cqMPAvNs9DS6tSZtNpNknGq7w1ehq YH+vBSAd7m0ipLoQ5FeMgLvO6/X2GtptppMOjRLZyXvE+3Uhgrdl35mMevcsX+m8ZYZ2UikpngUeX cKOgGW4WSmOPViWQDJt3TQFB8dWPgk+WvmB/eyZPblFsOp4PdHFco4LOocrk8DYJD9s7KZyx7rzRn 7V6DKf6R8CWulKwCXVtB7veO8vpuuP+a3oYQHDu3t9x/s/wW8CrEQdcBddN++RKuq7SUWHmtaYQjv hTuTQfGQ==; Received: from [2001:4bb8:184:72db:6d44:b004:a9fa:2cf3] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1mQlUB-00GP6z-5c; Thu, 16 Sep 2021 07:07:13 +0000 From: Christoph Hellwig To: Geert Uytterhoeven , Greg Ungerer Cc: Michael Schmitz , Linus Torvalds , linux-m68k@lists.linux-m68k.org Subject: [PATCH 5/6] m68k: provide __{get,put}_kernel_nofault Date: Thu, 16 Sep 2021 09:04:04 +0200 Message-Id: <20210916070405.52750-6-hch@lst.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210916070405.52750-1-hch@lst.de> References: <20210916070405.52750-1-hch@lst.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: linux-m68k@vger.kernel.org Allow non-faulting access to kernel addresses without overriding the address space. Implemented by passing the instruction name to the low-level assembly macros as an argument, and force the use of the normal move instructions for kernel access. Signed-off-by: Christoph Hellwig --- arch/m68k/include/asm/uaccess.h | 105 +++++++++++++++++++++++++------- 1 file changed, 84 insertions(+), 21 deletions(-) diff --git a/arch/m68k/include/asm/uaccess.h b/arch/m68k/include/asm/uaccess.h index 288ef7d11a7a3..65581a7874d4d 100644 --- a/arch/m68k/include/asm/uaccess.h +++ b/arch/m68k/include/asm/uaccess.h @@ -39,9 +39,9 @@ static inline int access_ok(const void __user *addr, #define MOVES "move" #endif -#define __put_user_asm(res, x, ptr, bwl, reg, err) \ +#define __put_user_asm(inst, res, x, ptr, bwl, reg, err) \ asm volatile ("\n" \ - "1: "MOVES"."#bwl" %2,%1\n" \ + "1: "inst"."#bwl" %2,%1\n" \ "2:\n" \ " .section .fixup,\"ax\"\n" \ " .even\n" \ @@ -57,13 +57,13 @@ asm volatile ("\n" \ : "+d" (res), "=m" (*(ptr)) \ : #reg (x), "i" (err)) -#define __put_user_asm8(res, x, ptr) \ +#define __put_user_asm8(inst, res, x, ptr) \ do { \ const void *__pu_ptr = (const void __force *)(ptr); \ \ asm volatile ("\n" \ - "1: "MOVES".l %2,(%1)+\n" \ - "2: "MOVES".l %R2,(%1)\n" \ + "1: "inst".l %2,(%1)+\n" \ + "2: "inst".l %R2,(%1)\n" \ "3:\n" \ " .section .fixup,\"ax\"\n" \ " .even\n" \ @@ -94,16 +94,16 @@ do { \ __chk_user_ptr(ptr); \ switch (sizeof (*(ptr))) { \ case 1: \ - __put_user_asm(__pu_err, __pu_val, ptr, b, d, -EFAULT); \ + __put_user_asm(MOVES, __pu_err, __pu_val, ptr, b, d, -EFAULT); \ break; \ case 2: \ - __put_user_asm(__pu_err, __pu_val, ptr, w, r, -EFAULT); \ + __put_user_asm(MOVES, __pu_err, __pu_val, ptr, w, r, -EFAULT); \ break; \ case 4: \ - __put_user_asm(__pu_err, __pu_val, ptr, l, r, -EFAULT); \ + __put_user_asm(MOVES, __pu_err, __pu_val, ptr, l, r, -EFAULT); \ break; \ case 8: \ - __put_user_asm8(__pu_err, __pu_val, ptr); \ + __put_user_asm8(MOVES, __pu_err, __pu_val, ptr); \ break; \ default: \ BUILD_BUG(); \ @@ -113,10 +113,10 @@ do { \ #define put_user(x, ptr) __put_user(x, ptr) -#define __get_user_asm(res, x, ptr, type, bwl, reg, err) ({ \ +#define __get_user_asm(inst, res, x, ptr, type, bwl, reg, err) ({ \ type __gu_val; \ asm volatile ("\n" \ - "1: "MOVES"."#bwl" %2,%1\n" \ + "1: "inst"."#bwl" %2,%1\n" \ "2:\n" \ " .section .fixup,\"ax\"\n" \ " .even\n" \ @@ -134,7 +134,7 @@ do { \ (x) = (__force typeof(*(ptr)))(__force unsigned long)__gu_val; \ }) -#define __get_user_asm8(res, x, ptr) \ +#define __get_user_asm8(inst, res, x, ptr) \ do { \ const void *__gu_ptr = (const void __force *)(ptr); \ union { \ @@ -143,8 +143,8 @@ do { \ } __gu_val; \ \ asm volatile ("\n" \ - "1: "MOVES".l (%2)+,%1\n" \ - "2: "MOVES".l (%2),%R1\n" \ + "1: "inst".l (%2)+,%1\n" \ + "2: "inst".l (%2),%R1\n" \ "3:\n" \ " .section .fixup,\"ax\"\n" \ " .even\n" \ @@ -172,16 +172,16 @@ do { \ __chk_user_ptr(ptr); \ switch (sizeof(*(ptr))) { \ case 1: \ - __get_user_asm(__gu_err, x, ptr, u8, b, d, -EFAULT); \ + __get_user_asm(MOVES, __gu_err, x, ptr, u8, b, d, -EFAULT); \ break; \ case 2: \ - __get_user_asm(__gu_err, x, ptr, u16, w, r, -EFAULT); \ + __get_user_asm(MOVES, __gu_err, x, ptr, u16, w, r, -EFAULT); \ break; \ case 4: \ - __get_user_asm(__gu_err, x, ptr, u32, l, r, -EFAULT); \ + __get_user_asm(MOVES, __gu_err, x, ptr, u32, l, r, -EFAULT); \ break; \ case 8: \ - __get_user_asm8(__gu_err, x, ptr); \ + __get_user_asm8(MOVES, __gu_err, x, ptr); \ break; \ default: \ BUILD_BUG(); \ @@ -330,16 +330,19 @@ __constant_copy_to_user(void __user *to, const void *from, unsigned long n) switch (n) { case 1: - __put_user_asm(res, *(u8 *)from, (u8 __user *)to, b, d, 1); + __put_user_asm(MOVES, res, *(u8 *)from, (u8 __user *)to, + b, d, 1); break; case 2: - __put_user_asm(res, *(u16 *)from, (u16 __user *)to, w, r, 2); + __put_user_asm(MOVES, res, *(u16 *)from, (u16 __user *)to, + w, r, 2); break; case 3: __constant_copy_to_user_asm(res, to, from, tmp, 3, w, b,); break; case 4: - __put_user_asm(res, *(u32 *)from, (u32 __user *)to, l, r, 4); + __put_user_asm(MOVES, res, *(u32 *)from, (u32 __user *)to, + l, r, 4); break; case 5: __constant_copy_to_user_asm(res, to, from, tmp, 5, l, b,); @@ -388,6 +391,66 @@ raw_copy_to_user(void __user *to, const void *from, unsigned long n) #define INLINE_COPY_FROM_USER #define INLINE_COPY_TO_USER +#define HAVE_GET_KERNEL_NOFAULT + +#define __get_kernel_nofault(dst, src, type, err_label) \ +do { \ + type *__gk_dst = (type *)(dst); \ + type *__gk_src = (type *)(src); \ + int __gk_err = 0; \ + \ + switch (sizeof(type)) { \ + case 1: \ + __get_user_asm("move", __gk_err, *__gk_dst, __gk_src, \ + u8, b, d, -EFAULT); \ + break; \ + case 2: \ + __get_user_asm("move", __gk_err, *__gk_dst, __gk_src, \ + u16, w, r, -EFAULT); \ + break; \ + case 4: \ + __get_user_asm("move", __gk_err, *__gk_dst, __gk_src, \ + u32, l, r, -EFAULT); \ + break; \ + case 8: \ + __get_user_asm8("move", __gk_err, *__gk_dst, __gk_src); \ + break; \ + default: \ + BUILD_BUG(); \ + } \ + if (unlikely(__gk_err)) \ + goto err_label; \ +} while (0) + +#define __put_kernel_nofault(dst, src, type, err_label) \ +do { \ + type __pk_src = *(type *)(src); \ + type *__pk_dst = (type *)(dst); \ + int __pk_err = 0; \ + \ + switch (sizeof(type)) { \ + case 1: \ + __put_user_asm("move", __pk_err, __pk_src, __pk_dst, \ + b, d, -EFAULT); \ + break; \ + case 2: \ + __put_user_asm("move", __pk_err, __pk_src, __pk_dst, \ + w, r, -EFAULT); \ + break; \ + case 4: \ + __put_user_asm("move", __pk_err, __pk_src, __pk_dst, \ + l, r, -EFAULT); \ + break; \ + case 8: \ + __put_user_asm8("move", __pk_err, __pk_src, __pk_dst); \ + break; \ + default: \ + BUILD_BUG(); \ + } \ + if (unlikely(__pk_err)) \ + goto err_label; \ +} while (0) + #define user_addr_max() \ (uaccess_kernel() ? ~0UL : TASK_SIZE) -- 2.30.2