From patchwork Mon Dec 10 23:21:39 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 10722757 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 85F9618E8 for ; Mon, 10 Dec 2018 23:22:16 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 762742A710 for ; Mon, 10 Dec 2018 23:22:16 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6A39D2A711; Mon, 10 Dec 2018 23:22:16 +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 1210A2A71B for ; Mon, 10 Dec 2018 23:22:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729868AbeLJXWA (ORCPT ); Mon, 10 Dec 2018 18:22:00 -0500 Received: from mga04.intel.com ([192.55.52.120]:11277 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727852AbeLJXV7 (ORCPT ); Mon, 10 Dec 2018 18:21:59 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 10 Dec 2018 15:21:57 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,340,1539673200"; d="scan'208";a="117684777" Received: from sjchrist-coffee.jf.intel.com ([10.54.74.154]) by orsmga001.jf.intel.com with ESMTP; 10 Dec 2018 15:21:57 -0800 From: Sean Christopherson To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, Jarkko Sakkinen , Sean Christopherson , Dave Hansen , Andy Lutomirski , Peter Zijlstra Cc: "H. Peter Anvin" , linux-kernel@vger.kernel.org, linux-sgx@vger.kernel.org, Andy Lutomirski , Josh Triplett , Haitao Huang , Jethro Beekman , "Dr . Greg Wettstein" Subject: [RFC PATCH v3 2/4] x86/fault: Attempt to fixup unhandled #PF on ENCLU before signaling Date: Mon, 10 Dec 2018 15:21:39 -0800 Message-Id: <20181210232141.5425-3-sean.j.christopherson@intel.com> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181210232141.5425-1-sean.j.christopherson@intel.com> References: <20181210232141.5425-1-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 X-Virus-Scanned: ClamAV using ClamSMTP Call fixup_sgx_enclu_exception() in the SIGSEGV and SIGBUS paths of the page fault handler immediately prior to signaling. If the fault is fixed, return cleanly and do not generate a signal. In the SIGSEGV flow, make sure the error code passed to userspace has been sanitized. Cc: Andy Lutomirski Cc: Jarkko Sakkinen Cc: Dave Hansen Cc: Josh Triplett Signed-off-by: Sean Christopherson --- arch/x86/mm/fault.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 7e8a7558ca07..d3903965334c 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -28,6 +28,7 @@ #include /* vma_pkey() */ #include /* efi_recover_from_page_fault()*/ #include /* store_idt(), ... */ +#include /* fixup_sgx_enclu_exception() */ #define CREATE_TRACE_POINTS #include @@ -928,6 +929,9 @@ __bad_area_nosemaphore(struct pt_regs *regs, unsigned long error_code, if (address >= TASK_SIZE_MAX) error_code |= X86_PF_PROT; + if (fixup_sgx_enclu_exception(regs, X86_TRAP_PF, error_code, address)) + return; + if (likely(show_unhandled_signals)) show_signal_msg(regs, error_code, address, tsk); @@ -1045,6 +1049,9 @@ do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address, if (is_prefetch(regs, error_code, address)) return; + if (fixup_sgx_enclu_exception(regs, X86_TRAP_PF, error_code, address)) + return; + set_signal_archinfo(address, error_code); #ifdef CONFIG_MEMORY_FAILURE