From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ua0-f200.google.com (mail-ua0-f200.google.com [209.85.217.200]) by kanga.kvack.org (Postfix) with ESMTP id E20176B0266 for ; Mon, 22 Aug 2016 18:39:04 -0400 (EDT) Received: by mail-ua0-f200.google.com with SMTP id u13so265091829uau.2 for ; Mon, 22 Aug 2016 15:39:04 -0700 (PDT) Received: from NAM02-BL2-obe.outbound.protection.outlook.com (mail-bl2nam02on0054.outbound.protection.outlook.com. [104.47.38.54]) by mx.google.com with ESMTPS id m189si256204qkd.39.2016.08.22.15.39.04 for (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 22 Aug 2016 15:39:04 -0700 (PDT) From: Tom Lendacky Subject: [RFC PATCH v2 19/20] x86: Access the setup data through debugfs un-encrypted Date: Mon, 22 Aug 2016 17:38:59 -0500 Message-ID: <20160822223859.29880.60652.stgit@tlendack-t1.amdoffice.net> In-Reply-To: <20160822223529.29880.50884.stgit@tlendack-t1.amdoffice.net> References: <20160822223529.29880.50884.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: Radim =?utf-8?b?S3LEjW3DocWZ?= , Arnd Bergmann , Jonathan Corbet , Matt Fleming , Joerg Roedel , Konrad Rzeszutek Wilk , Andrey Ryabinin , Ingo Molnar , Borislav Petkov , Andy Lutomirski , "H. Peter Anvin" , Paolo Bonzini , 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