From patchwork Sat Jul 13 17:07:55 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 11043111 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AE4E1138D for ; Sat, 13 Jul 2019 17:11:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 982CF27816 for ; Sat, 13 Jul 2019 17:11:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8B4202835B; Sat, 13 Jul 2019 17:11:56 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1C0A727816 for ; Sat, 13 Jul 2019 17:11:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728169AbfGMRLz (ORCPT ); Sat, 13 Jul 2019 13:11:55 -0400 Received: from mga07.intel.com ([134.134.136.100]:36880 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728086AbfGMRLz (ORCPT ); Sat, 13 Jul 2019 13:11:55 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 13 Jul 2019 10:11:55 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.63,487,1557212400"; d="scan'208";a="341981518" Received: from hbriegel-mobl.ger.corp.intel.com (HELO localhost) ([10.252.50.48]) by orsmga005.jf.intel.com with ESMTP; 13 Jul 2019 10:11:46 -0700 From: Jarkko Sakkinen To: linux-kernel@vger.kernel.org, x86@kernel.org, linux-sgx@vger.kernel.org Cc: akpm@linux-foundation.org, dave.hansen@intel.com, sean.j.christopherson@intel.com, nhorman@redhat.com, npmccallum@redhat.com, serge.ayoun@intel.com, shay.katz-zamir@intel.com, haitao.huang@intel.com, andriy.shevchenko@linux.intel.com, tglx@linutronix.de, kai.svahn@intel.com, bp@alien8.de, josh@joshtriplett.org, luto@kernel.org, kai.huang@intel.com, rientjes@google.com, cedric.xing@intel.com, Jarkko Sakkinen Subject: [PATCH v21 19/28] x86/sgx: ptrace() support for the SGX driver Date: Sat, 13 Jul 2019 20:07:55 +0300 Message-Id: <20190713170804.2340-20-jarkko.sakkinen@linux.intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190713170804.2340-1-jarkko.sakkinen@linux.intel.com> References: <20190713170804.2340-1-jarkko.sakkinen@linux.intel.com> MIME-Version: 1.0 Sender: linux-sgx-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add VMA callbacks for ptrace() that can be used with debug enclaves. With debug enclaves data can be read and write the memory word at a time by using ENCLS(EDBGRD) and ENCLS(EDBGWR) leaf instructions. Signed-off-by: Jarkko Sakkinen --- arch/x86/kernel/cpu/sgx/encl.c | 98 ++++++++++++++++++++++++++++++++++ 1 file changed, 98 insertions(+) diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c index 6bde020e8cfa..836c55d4352d 100644 --- a/arch/x86/kernel/cpu/sgx/encl.c +++ b/arch/x86/kernel/cpu/sgx/encl.c @@ -329,6 +329,7 @@ int sgx_encl_may_map(struct sgx_encl *encl, unsigned long start, return 0; } + static int sgx_vma_mprotect(struct vm_area_struct *vma, unsigned long start, unsigned long end, unsigned long prot) { @@ -336,10 +337,107 @@ static int sgx_vma_mprotect(struct vm_area_struct *vma, unsigned long start, calc_vm_prot_bits(prot, 0)); } +static int sgx_edbgrd(struct sgx_encl *encl, struct sgx_encl_page *page, + unsigned long addr, void *data) +{ + unsigned long offset; + int ret; + + offset = addr & ~PAGE_MASK; + + if ((page->desc & SGX_ENCL_PAGE_TCS) && + offset > offsetof(struct sgx_tcs, gs_limit)) + return -ECANCELED; + + ret = __edbgrd(sgx_epc_addr(page->epc_page) + offset, data); + if (ret) + return -EIO; + + return 0; +} + +static int sgx_edbgwr(struct sgx_encl *encl, struct sgx_encl_page *page, + unsigned long addr, void *data) +{ + unsigned long offset; + int ret; + + offset = addr & ~PAGE_MASK; + + /* Writing anything else than flags will cause #GP */ + if ((page->desc & SGX_ENCL_PAGE_TCS) && + offset != offsetof(struct sgx_tcs, flags)) + return -ECANCELED; + + ret = __edbgwr(sgx_epc_addr(page->epc_page) + offset, data); + if (ret) + return -EIO; + + return 0; +} + +static int sgx_vma_access(struct vm_area_struct *vma, unsigned long addr, + void *buf, int len, int write) +{ + struct sgx_encl *encl = vma->vm_private_data; + struct sgx_encl_page *entry = NULL; + unsigned long align; + char data[sizeof(unsigned long)]; + int offset; + int cnt; + int ret = 0; + int i; + + /* If process was forked, VMA is still there but vm_private_data is set + * to NULL. + */ + if (!encl) + return -EFAULT; + + if (!(encl->flags & SGX_ENCL_DEBUG) || + !(encl->flags & SGX_ENCL_INITIALIZED) || + (encl->flags & SGX_ENCL_DEAD)) + return -EFAULT; + + for (i = 0; i < len; i += cnt) { + entry = sgx_encl_reserve_page(encl, (addr + i) & PAGE_MASK); + if (IS_ERR(entry)) { + ret = PTR_ERR(entry); + break; + } + + align = ALIGN_DOWN(addr + i, sizeof(unsigned long)); + offset = (addr + i) & (sizeof(unsigned long) - 1); + cnt = sizeof(unsigned long) - offset; + cnt = min(cnt, len - i); + + ret = sgx_edbgrd(encl, entry, align, data); + if (ret) + goto out; + + if (write) { + memcpy(data + offset, buf + i, cnt); + ret = sgx_edbgwr(encl, entry, align, data); + if (ret) + goto out; + } else + memcpy(buf + i, data + offset, cnt); + +out: + mutex_unlock(&encl->lock); + + if (ret) + break; + } + + return ret < 0 ? ret : i; +} + const struct vm_operations_struct sgx_vm_ops = { .open = sgx_vma_open, .fault = sgx_vma_fault, .may_mprotect = sgx_vma_mprotect, + .access = sgx_vma_access, }; /**