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 2A32FC433F5 for ; Wed, 11 May 2022 02:30:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241549AbiEKCaw (ORCPT ); Tue, 10 May 2022 22:30:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50800 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241267AbiEKC3p (ORCPT ); Tue, 10 May 2022 22:29:45 -0400 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4DDD721AABC for ; Tue, 10 May 2022 19:29:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1652236184; x=1683772184; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=tVhiT6aKeF/Rpr/dJksjmlkONreh2kMGvoLBNiaVHv4=; b=E032CCyWLsZ6zZQXqH4b94PYGQ8IAR13GteQ5ZPd6vKWxRzzWi997eZT 7BICAZUNV/bSZlngp/luXJ9CUKzTmJa8u8WZFiuVOuJnM2Tmt8CSikFFU J+OFxIbUvrWD/wYoTrFQLMpMpUPfoqtlR9pffeoNkT2x3cnF0o9vkJk9g Sd73qGk0Xkunfm8XVuCKdtgqKC1eJsE7Uw09b6sblXuvKSnGxfXujNrLz qE9TKqLZD17/syHM/xxH+jKQOUPN7pH7ljDdhj6lX+SaNaNV/dGSQF9oc nWbw1xOriSAZLnpD6XKSPBgt9vwvx6MwMAg2K9gyflaG2+m0p2Bfe8bQi A==; X-IronPort-AV: E=McAfee;i="6400,9594,10343"; a="294798606" X-IronPort-AV: E=Sophos;i="5.91,215,1647327600"; d="scan'208";a="294798606" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 May 2022 19:29:43 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.91,215,1647327600"; d="scan'208";a="553112425" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga002.jf.intel.com with ESMTP; 10 May 2022 19:29:40 -0700 Received: by black.fi.intel.com (Postfix, from userid 1000) id 495565C1; Wed, 11 May 2022 05:28:01 +0300 (EEST) From: "Kirill A. Shutemov" To: Dave Hansen , Andy Lutomirski , Peter Zijlstra Cc: x86@kernel.org, Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , "H . J . Lu" , Andi Kleen , Rick Edgecombe , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Subject: [RFCv2 06/10] x86/uaccess: Remove tags from the address before checking Date: Wed, 11 May 2022 05:27:47 +0300 Message-Id: <20220511022751.65540-8-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220511022751.65540-1-kirill.shutemov@linux.intel.com> References: <20220511022751.65540-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The tags must not be included into check whether it's okay to access the userspace address. Strip tags in access_ok(). get_user() and put_user() don't use access_ok(), but check access against TASK_SIZE directly in assembly. Strip tags, before calling into the assembly helper. Signed-off-by: Kirill A. Shutemov --- arch/x86/include/asm/uaccess.h | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index f78e2b3501a1..0f5bf7db4ec9 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -40,7 +40,7 @@ static inline bool pagefault_disabled(void); #define access_ok(addr, size) \ ({ \ WARN_ON_IN_IRQ(); \ - likely(__access_ok(addr, size)); \ + likely(__access_ok(untagged_addr(addr), size)); \ }) #include @@ -125,7 +125,12 @@ extern int __get_user_bad(void); * Return: zero on success, or -EFAULT on error. * On error, the variable @x is set to zero. */ -#define get_user(x,ptr) ({ might_fault(); do_get_user_call(get_user,x,ptr); }) +#define get_user(x,ptr) \ +({ \ + __typeof__(*(ptr)) __user *__ptr_clean = untagged_ptr(ptr); \ + might_fault(); \ + do_get_user_call(get_user,x,__ptr_clean); \ +}) /** * __get_user - Get a simple variable from user space, with less checking. @@ -222,7 +227,11 @@ extern void __put_user_nocheck_8(void); * * Return: zero on success, or -EFAULT on error. */ -#define put_user(x, ptr) ({ might_fault(); do_put_user_call(put_user,x,ptr); }) +#define put_user(x, ptr) ({ \ + __typeof__(*(ptr)) __user *__ptr_clean = untagged_ptr(ptr); \ + might_fault(); \ + do_put_user_call(put_user,x,__ptr_clean); \ +}) /** * __put_user - Write a simple value into user space, with less checking. -- 2.35.1