From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9929AFA3728 for ; Wed, 16 Oct 2019 11:19:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 68BF32067B for ; Wed, 16 Oct 2019 11:19:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392759AbfJPLTX (ORCPT ); Wed, 16 Oct 2019 07:19:23 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:40229 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392704AbfJPLTU (ORCPT ); Wed, 16 Oct 2019 07:19:20 -0400 Received: from [213.220.153.21] (helo=localhost.localdomain) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1iKhKo-0003tb-0H; Wed, 16 Oct 2019 11:19:18 +0000 From: Christian Brauner To: christian.brauner@ubuntu.com Cc: ast@kernel.org, bpf@vger.kernel.org, daniel@iogearbox.net, kafai@fb.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, songliubraving@fb.com, yhs@fb.com Subject: [PATCH bpf-next v4 0/3] bpf: switch to new usercopy helpers Date: Wed, 16 Oct 2019 13:18:07 +0200 Message-Id: <20191016111810.1799-1-christian.brauner@ubuntu.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191016034432.4418-1-christian.brauner@ubuntu.com> References: <20191016034432.4418-1-christian.brauner@ubuntu.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hey everyone, This is v4. If you still feel that I should leave this code alone then simply ignore it. I won't send another version. Relevant tests pass and I've verified that other failures were already present without this patch series applied. The misplaced min check has been moved after copy_struct_from_user() so no non-zero bytes can be missed by copy_struct_from_user(). In v5.4-rc2 we added two new helpers check_zeroed_user() and copy_struct_from_user() including selftests (cf. [1]). It is a generic interface designed to copy a struct from userspace. The helpers will be especially useful for structs versioned by size of which we have quite a few. The most obvious benefit is that this helper lets us get rid of duplicate code. We've already switched over sched_setattr(), perf_event_open(), and clone3(). More importantly it will also help to ensure that users implementing versioning-by-size end up with the same core semantics. This point is especially crucial since we have at least one case where versioning-by-size is used but with slighly different semantics: sched_setattr(), perf_event_open(), and clone3() all do do similar checks to copy_struct_from_user() while rt_sigprocmask(2) always rejects differently-sized struct arguments. This little series switches over bpf codepaths that have hand-rolled implementations of these helpers. /* v1 */ Link: https://lore.kernel.org/r/20191009160907.10981-1-christian.brauner@ubuntu.com /* v2 */ Link: https://lore.kernel.org/r/20191016004138.24845-1-christian.brauner@ubuntu.com - rebase onto bpf-next /* v3 */ Link: https://lore.kernel.org/r/20191016034432.4418-1-christian.brauner@ubuntu.com /* Reference */ [1]: f5a1a536fa14 ("lib: introduce copy_struct_from_user() helper") Christian Brauner (3): bpf: use check_zeroed_user() in bpf_check_uarg_tail_zero() bpf: use copy_struct_from_user() in bpf_prog_get_info_by_fd() bpf: use copy_struct_from_user() in bpf() syscall kernel/bpf/syscall.c | 39 ++++++++++++--------------------------- 1 file changed, 12 insertions(+), 27 deletions(-) -- 2.23.0