From patchwork Thu Oct 10 22:55:27 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 11184549 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0898418B7 for ; Thu, 10 Oct 2019 22:55:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DE1C120B7C for ; Thu, 10 Oct 2019 22:55:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726671AbfJJWzj (ORCPT ); Thu, 10 Oct 2019 18:55:39 -0400 Received: from mga06.intel.com ([134.134.136.31]:20137 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726559AbfJJWzj (ORCPT ); Thu, 10 Oct 2019 18:55:39 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 10 Oct 2019 15:55:38 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.67,281,1566889200"; d="scan'208";a="197400448" Received: from sjchrist-coffee.jf.intel.com ([10.54.74.41]) by orsmga003.jf.intel.com with ESMTP; 10 Oct 2019 15:55:38 -0700 From: Sean Christopherson To: Jarkko Sakkinen Cc: linux-sgx@vger.kernel.org Subject: [PATCH for_v23 1/4] x86/sgx: Pass EADD the kernel's virtual address for the source page Date: Thu, 10 Oct 2019 15:55:27 -0700 Message-Id: <20191010225530.26400-2-sean.j.christopherson@intel.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20191010225530.26400-1-sean.j.christopherson@intel.com> References: <20191010225530.26400-1-sean.j.christopherson@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 Use the kernel's virtual address to reference the source page when EADDing a page to the enclave. gup() "does not guarantee that the page exists in the user mappings", i.e. EADD can still fault and deadlock due to mmap_sem contention if it consumes the userspace address. Signed-off-by: Sean Christopherson --- arch/x86/kernel/cpu/sgx/ioctl.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c index eeed919ed3e2..62965d003fda 100644 --- a/arch/x86/kernel/cpu/sgx/ioctl.c +++ b/arch/x86/kernel/cpu/sgx/ioctl.c @@ -328,16 +328,14 @@ static int __sgx_encl_add_page(struct sgx_encl *encl, if (ret < 1) return ret; - __uaccess_begin(); - pginfo.secs = (unsigned long)sgx_epc_addr(encl->secs.epc_page); pginfo.addr = SGX_ENCL_PAGE_ADDR(encl_page); pginfo.metadata = (unsigned long)secinfo; - pginfo.contents = (unsigned long)src; + pginfo.contents = (unsigned long)kmap_atomic(src_page); ret = __eadd(&pginfo, sgx_epc_addr(epc_page)); - __uaccess_end(); + kunmap_atomic((void *)pginfo.contents); put_page(src_page); return ret ? -EFAULT : 0;