From patchwork Fri Aug 25 13:32:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jo Van Bulck X-Patchwork-Id: 13365695 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 99994EE49B4 for ; Fri, 25 Aug 2023 13:33:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245114AbjHYNd0 (ORCPT ); Fri, 25 Aug 2023 09:33:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38872 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245085AbjHYNdQ (ORCPT ); Fri, 25 Aug 2023 09:33:16 -0400 Received: from icts-p-cavuit-3.kulnet.kuleuven.be (icts-p-cavuit-3.kulnet.kuleuven.be [134.58.240.133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5D7BF1FDE; Fri, 25 Aug 2023 06:33:14 -0700 (PDT) X-KULeuven-Envelope-From: jo.vanbulck@cs.kuleuven.be X-KULeuven-Scanned: Found to be clean X-KULeuven-ID: 49882201B7.AE660 X-KULeuven-Information: Katholieke Universiteit Leuven Received: from icts-p-ceifnet-smtps-0.kuleuven.be (icts-p-ceifnet-smtps.service.icts.svcd [IPv6:2a02:2c40:0:51:144:242:ac11:2f]) by icts-p-cavuit-3.kulnet.kuleuven.be (Postfix) with ESMTP id 49882201B7; Fri, 25 Aug 2023 15:33:09 +0200 (CEST) BCmilterd-Mark-Subject: no BCmilterd-Errors: BCmilterd-Report: SA-HVU#DKIM_VALID_AU#0.00,SA-HVU#DKIM_SIGNED#0.00,SA-HVU#DKIM_VALID#0.00 X-CAV-Cluster: smtps DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cs.kuleuven.be; s=cav; t=1692970389; bh=vp8fkTfpj2pMBJhMKyDWMekB7qDxhVJsvFbpU7SdwIA=; h=From:To:Cc:Subject:Date; b=Hk8wwfmyaZ+4xbEIESYyXe4X9JkBqz482Q+7M9zBgTvBO51IQLD6dM/FMrGIbA7xr v+W5nXcls31Za+kwNCh6wwYy/BRvdrBDyYeVzWs4aTE52jHWglLjSqGzR2yYakgTmY yzKa+kvG//ChrUdw2NIv7Qf2OVEDC3vlhvyYpsc4= Received: from localhost.localdomain (ptr-82s0fs8e775rpuqrs36.18120a2.ip6.access.telenet.be [IPv6:2a02:1811:d31:8b00:b56b:371:2317:a8f2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by icts-p-ceifnet-smtps-0.kuleuven.be (Postfix) with ESMTPSA id 03C15D4F7F13B; Fri, 25 Aug 2023 15:33:08 +0200 (CEST) X-Kuleuven: This mail passed the K.U.Leuven mailcluster From: Jo Van Bulck To: jarkko@kernel.org, kai.huang@intel.com, linux-sgx@vger.kernel.org, linux-kernel@vger.kernel.org Cc: dave.hansen@linux.intel.com, Jo Van Bulck Subject: [PATCH v4 00/13] selftests/sgx: Fix compilation errors Date: Fri, 25 Aug 2023 15:32:39 +0200 Message-Id: <20230825133252.9056-1-jo.vanbulck@cs.kuleuven.be> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org Hi, This is the fourth iteration of a patch series to ensure that all SGX selftests succeed when compiling with optimizations (as tested with -O{0,1,2,3,s} for both gcc 11.3.0 and clang 14.0.0). The aim of the patches is to avoid reliance on undefined, compiler-specific behavior that can make the test results fragile. This series appends 4 new commits compared to the previous series (do let me know if appending commits to this series is not the preferred way to handle these?): 1. Another fix for possibly uninitialized pointer dereferences in encl_get_entry. Note that this was only brought up as a compiler warning when compiling the loader itself (i.e., not only the enclave) with optimizations. Also not that the uninitialized pointers shouldn't show up for "well-formed" enclave ELF files that properly contain a symbol table section, but I considered it is nevertheless good practice to harden the code against this (unlikely) case. 2. Split off the ".dyn*" and ".gnu.hash" discarding in a separate commit, as suggested by Kay [1]. 3. Split off the removal of the redundant push/pop pair in a separate commit, as suggested by Kai [2]. 4. Remove all (incomplete) CPU register cleansing assembly code on enclave exit, reflecting earlier discussions that highlight that the test enclave should *not* be confused with exemplary, security-hardened enclave code, and in line with Dave's suggestion to make the test enclave more *obviously* insecure [3]. If useful, I can also include an elementary wrapper shell script to compile and run the tests for different compilers (gcc/clang) and optimization levels. Reference output below: .. Testing gcc -O0 [OK] .. Testing gcc -O1 [OK] .. Testing gcc -O2 [OK] .. Testing gcc -O3 [OK] .. Testing gcc -Os [OK] .. Testing gcc -Ofast [OK] .. Testing gcc -Og [OK] .. Testing clang -O0 [OK] .. Testing clang -O1 [OK] .. Testing clang -O2 [OK] .. Testing clang -O3 [OK] .. Testing clang -Os [OK] .. Testing clang -Ofast [OK] .. Testing clang -Og [OK] Changelog --------- v4 - Remove redundant -nostartfiles compiler flag (Jarkko) - Split dynamic symbol table removal in separate commit (Kai) - Split redundant push/pop elimination in separate commit (Kai) - Remove (incomplete) register cleansing on enclave exit - Fix possibly uninitialized pointer dereferences in load.c v3 - Refactor encl_op_array declaration and indexing (Jarkko) - Annotate encl_buffer with "used" attribute (Kai) - Split encl_buffer size and placement commits (Kai) v2 - Add additional check for NULL pointer (Kai) - Refine to produce proper static-pie executable - Fix linker script assertions - Specify memory clobber for inline asm instead of volatile (Kai) - Clarify why encl_buffer non-static (Jarkko, Kai) - Clarify -ffreestanding (Jarkko) References ---------- [1] https://lore.kernel.org/all/90ad8638bc1c26505e33b3f436fdbc22c8d74ba9.camel@intel.com/ [2] https://lore.kernel.org/all/71ad6389da7db8541dada0276db33f98e2a4fdcf.camel@intel.com/ [3] https://lore.kernel.org/all/da0cfb1e-e347-f7f2-ac72-aec0ee0d867d@intel.com/ Best, Jo Jo Van Bulck (13): selftests/sgx: Fix uninitialized pointer dereference in error path selftests/sgx: Produce static-pie executable for test enclave selftests/sgx: Handle relocations in test enclave selftests/sgx: Fix linker script asserts selftests/sgx: Include memory clobber for inline asm in test enclave selftests/sgx: Ensure test enclave buffer is entirely preserved selftests/sgx: Ensure expected location of test enclave buffer selftests/sgx: Separate linker options selftests/sgx: Specify freestanding environment for enclave compilation selftests/sgx: Fix uninitialized pointer dereferences selftests/sgx: Discard unsupported ELF sections selftests/sgx: Remove redundant enclave base address save/restore selftests/sgx: Remove incomplete ABI sanitization code in test enclave tools/testing/selftests/sgx/Makefile | 14 ++-- tools/testing/selftests/sgx/defines.h | 2 + tools/testing/selftests/sgx/load.c | 9 ++- tools/testing/selftests/sgx/sigstruct.c | 5 +- tools/testing/selftests/sgx/test_encl.c | 65 ++++++++++++------- tools/testing/selftests/sgx/test_encl.lds | 10 +-- .../selftests/sgx/test_encl_bootstrap.S | 28 +++----- 7 files changed, 76 insertions(+), 57 deletions(-)