From patchwork Tue Jun 28 16:19:48 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: KP Singh X-Patchwork-Id: 12898523 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 F185FCCA486 for ; Tue, 28 Jun 2022 16:30:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234688AbiF1QaT (ORCPT ); Tue, 28 Jun 2022 12:30:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46902 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347724AbiF1Q3O (ORCPT ); Tue, 28 Jun 2022 12:29:14 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CC3E23A1A0; Tue, 28 Jun 2022 09:20:06 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 7BAF7B81EF1; Tue, 28 Jun 2022 16:20:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8FF58C385A5; Tue, 28 Jun 2022 16:20:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1656433204; bh=9pchgL8YFP3Hx5Q02p0k2JNpsUBkX+zukfrJ3q2OcKI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=O5fRq5RidSwRGjSy3tClru4NFzOywFU0UFX7DH9LUOrUQsivUbrDr2uT4moov+Kkx KWZvUES4e4R03/T5Uy4dCylqjBtpiBzNRvEuK3KI8e9039f9K97/lLdPsSTtbqexx/ 4+vPwqQ8gSnHBApZIsgu3qVvau8NRIi9Dn5/9x1L2cqqh/+N5OzZ4MnZe/hvKo5Jv9 qJfFZPtGkGKXjZTtjlGTgGxgS2at0UEhleWIItaps/NFm4ZKWBpkMWJkh6ILYBQKj1 cj1c//KDlTwBWma3mZ1YGIZK2Z4YMIh+TGEvzh4Fm6w8CWj5s1amo8A1Wtt0Rdx8yb 4oJYwcD/CGTTA== From: KP Singh To: bpf@vger.kernel.org, linux-security-module@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: KP Singh , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Benjamin Tissoires , Yosry Ahmed Subject: [PATCH v5 bpf-next 5/5] bpf/selftests: Add a selftest for bpf_getxattr Date: Tue, 28 Jun 2022 16:19:48 +0000 Message-Id: <20220628161948.475097-6-kpsingh@kernel.org> X-Mailer: git-send-email 2.37.0.rc0.161.g10f37bed90-goog In-Reply-To: <20220628161948.475097-1-kpsingh@kernel.org> References: <20220628161948.475097-1-kpsingh@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: A simple test that adds an xattr on a copied /bin/ls and reads it back when the copied ls is executed. Signed-off-by: KP Singh --- .../testing/selftests/bpf/prog_tests/xattr.c | 54 +++++++++++++++++++ tools/testing/selftests/bpf/progs/xattr.c | 37 +++++++++++++ 2 files changed, 91 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/xattr.c create mode 100644 tools/testing/selftests/bpf/progs/xattr.c diff --git a/tools/testing/selftests/bpf/prog_tests/xattr.c b/tools/testing/selftests/bpf/prog_tests/xattr.c new file mode 100644 index 000000000000..ef07fa8a1763 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/xattr.c @@ -0,0 +1,54 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Copyright 2022 Google LLC. + */ + +#include +#include +#include "xattr.skel.h" + +#define XATTR_NAME "security.bpf" +#define XATTR_VALUE "test_progs" + +void test_xattr(void) +{ + struct xattr *skel = NULL; + char tmp_dir_path[] = "/tmp/xattrXXXXXX"; + char tmp_exec_path[64]; + char cmd[256]; + int err; + + if (CHECK_FAIL(!mkdtemp(tmp_dir_path))) + goto close_prog; + + snprintf(tmp_exec_path, sizeof(tmp_exec_path), "%s/copy_of_ls", + tmp_dir_path); + snprintf(cmd, sizeof(cmd), "cp /bin/ls %s", tmp_exec_path); + if (CHECK_FAIL(system(cmd))) + goto close_prog_rmdir; + + if (CHECK_FAIL(setxattr(tmp_exec_path, XATTR_NAME, XATTR_VALUE, + sizeof(XATTR_VALUE), 0))) + goto close_prog_rmdir; + + skel = xattr__open_and_load(); + if (!ASSERT_OK_PTR(skel, "skel_load")) + goto close_prog_rmdir; + + err = xattr__attach(skel); + if (!ASSERT_OK(err, "xattr__attach failed")) + goto close_prog_rmdir; + + snprintf(cmd, sizeof(cmd), "%s -l", tmp_exec_path); + if (CHECK_FAIL(system(cmd))) + goto close_prog_rmdir; + + ASSERT_EQ(skel->bss->result, 1, "xattr result"); + +close_prog_rmdir: + snprintf(cmd, sizeof(cmd), "rm -rf %s", tmp_dir_path); + system(cmd); +close_prog: + xattr__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/xattr.c b/tools/testing/selftests/bpf/progs/xattr.c new file mode 100644 index 000000000000..ccc078fb8ebd --- /dev/null +++ b/tools/testing/selftests/bpf/progs/xattr.c @@ -0,0 +1,37 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Copyright 2022 Google LLC. + */ + +#include "vmlinux.h" +#include +#include + +char _license[] SEC("license") = "GPL"; + +#define XATTR_NAME "security.bpf" +#define XATTR_VALUE "test_progs" + +__u64 result = 0; + +extern ssize_t bpf_getxattr(struct dentry *dentry, struct inode *inode, + const char *name, void *value, int size) __ksym; + +SEC("lsm.s/bprm_committed_creds") +void BPF_PROG(bprm_cc, struct linux_binprm *bprm) +{ + struct task_struct *current = bpf_get_current_task_btf(); + char dir_xattr_value[64] = {0}; + int xattr_sz = 0; + + xattr_sz = bpf_getxattr(bprm->file->f_path.dentry, + bprm->file->f_path.dentry->d_inode, XATTR_NAME, + dir_xattr_value, 64); + + if (xattr_sz <= 0) + return; + + if (!bpf_strncmp(dir_xattr_value, sizeof(XATTR_VALUE), XATTR_VALUE)) + result = 1; +}