From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yw0-f198.google.com (mail-yw0-f198.google.com [209.85.161.198]) by kanga.kvack.org (Postfix) with ESMTP id 92F746B0277 for ; Wed, 9 Nov 2016 19:38:23 -0500 (EST) Received: by mail-yw0-f198.google.com with SMTP id a10so90040046ywa.6 for ; Wed, 09 Nov 2016 16:38:23 -0800 (PST) Received: from NAM02-CY1-obe.outbound.protection.outlook.com (mail-cys01nam02on0060.outbound.protection.outlook.com. [104.47.37.60]) by mx.google.com with ESMTPS id g9si929516otd.217.2016.11.09.16.38.22 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 09 Nov 2016 16:38:22 -0800 (PST) From: Tom Lendacky Subject: [RFC PATCH v3 18/20] x86: Access the setup data through debugfs un-encrypted Date: Wed, 9 Nov 2016 18:38:15 -0600 Message-ID: <20161110003814.3280.56548.stgit@tlendack-t1.amdoffice.net> In-Reply-To: <20161110003426.3280.2999.stgit@tlendack-t1.amdoffice.net> References: <20161110003426.3280.2999.stgit@tlendack-t1.amdoffice.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: linux-arch@vger.kernel.org, linux-efi@vger.kernel.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, linux-mm@kvack.org, iommu@lists.linux-foundation.org Cc: Rik van Riel , Radim =?utf-8?b?S3LEjW3DocWZ?= , Arnd Bergmann , Jonathan Corbet , Matt Fleming , Joerg Roedel , Konrad Rzeszutek Wilk , Paolo Bonzini , Larry Woodman , Ingo Molnar , Borislav Petkov , Andy Lutomirski , "H. Peter Anvin" , Andrey Ryabinin , Alexander Potapenko , Thomas Gleixner , Dmitry Vyukov Since the setup data is in memory in the clear, it must be accessed as un-encrypted. Always use ioremap (similar to sysfs setup data support) to map the data. Signed-off-by: Tom Lendacky --- arch/x86/kernel/kdebugfs.c | 30 +++++++++++------------------- 1 file changed, 11 insertions(+), 19 deletions(-) diff --git a/arch/x86/kernel/kdebugfs.c b/arch/x86/kernel/kdebugfs.c index bdb83e4..a58a82e 100644 --- a/arch/x86/kernel/kdebugfs.c +++ b/arch/x86/kernel/kdebugfs.c @@ -48,17 +48,13 @@ static ssize_t setup_data_read(struct file *file, char __user *user_buf, pa = node->paddr + sizeof(struct setup_data) + pos; pg = pfn_to_page((pa + count - 1) >> PAGE_SHIFT); - if (PageHighMem(pg)) { - p = ioremap_cache(pa, count); - if (!p) - return -ENXIO; - } else - p = __va(pa); + p = ioremap_cache(pa, count); + if (!p) + return -ENXIO; remain = copy_to_user(user_buf, p, count); - if (PageHighMem(pg)) - iounmap(p); + iounmap(p); if (remain) return -EFAULT; @@ -127,15 +123,12 @@ static int __init create_setup_data_nodes(struct dentry *parent) } pg = pfn_to_page((pa_data+sizeof(*data)-1) >> PAGE_SHIFT); - if (PageHighMem(pg)) { - data = ioremap_cache(pa_data, sizeof(*data)); - if (!data) { - kfree(node); - error = -ENXIO; - goto err_dir; - } - } else - data = __va(pa_data); + data = ioremap_cache(pa_data, sizeof(*data)); + if (!data) { + kfree(node); + error = -ENXIO; + goto err_dir; + } node->paddr = pa_data; node->type = data->type; @@ -143,8 +136,7 @@ static int __init create_setup_data_nodes(struct dentry *parent) error = create_setup_data_node(d, no, node); pa_data = data->next; - if (PageHighMem(pg)) - iounmap(data); + iounmap(data); if (error) goto err_dir; no++; -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org