From patchwork Tue Aug 9 10:53:17 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Artem Savkov X-Patchwork-Id: 12939532 X-Patchwork-Delegate: bpf@iogearbox.net 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 0292FC19F2D for ; Tue, 9 Aug 2022 10:53:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242622AbiHIKx3 (ORCPT ); Tue, 9 Aug 2022 06:53:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59654 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237765AbiHIKx1 (ORCPT ); Tue, 9 Aug 2022 06:53:27 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 362985F63 for ; Tue, 9 Aug 2022 03:53:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1660042404; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=t3awSX3Tq4QpWeUfA1tbizxgPGHJw6AQeDWWE3eaTyI=; b=gxbeOaAx2fXwUt9wlBe+YypRB60huAA/sa4ja5WZQmUbZR6sdZ/OMPbtcDbwF4HdUyL3Za o+bkAjDWtqYd6cGQmEWS3LxVrhKdxzSd43FEDpLIAVefDWLle1CoZ3R3o/zQ5/4v+bdAdk eDSwcze7dl7cGJOAvclsU3kk9bdjk2M= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-651-PjBZ2mGmOIS8ho1mtfhAmg-1; Tue, 09 Aug 2022 06:53:19 -0400 X-MC-Unique: PjBZ2mGmOIS8ho1mtfhAmg-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 2F551811E87; Tue, 9 Aug 2022 10:53:19 +0000 (UTC) Received: from shodan.usersys.redhat.com (unknown [10.43.17.22]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E7862492C3B; Tue, 9 Aug 2022 10:53:18 +0000 (UTC) Received: by shodan.usersys.redhat.com (Postfix, from userid 1000) id 028C91C031E; Tue, 9 Aug 2022 12:53:18 +0200 (CEST) From: Artem Savkov To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , bpf@vger.kernel.org, netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Andrea Arcangeli , Daniel Vacek , Jiri Olsa , Song Liu , Daniel Xu , Kumar Kartikeya Dwivedi , Artem Savkov Subject: [PATCH bpf-next v4 3/3] selftests/bpf: add destructive kfunc test Date: Tue, 9 Aug 2022 12:53:17 +0200 Message-Id: <20220809105317.436682-4-asavkov@redhat.com> In-Reply-To: <20220809105317.436682-1-asavkov@redhat.com> References: <20220809105317.436682-1-asavkov@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.85 on 10.11.54.9 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Add a test checking that programs calling destructive kfuncs can only do so if they have CAP_SYS_BOOT capabilities. Signed-off-by: Artem Savkov --- net/bpf/test_run.c | 5 +++ .../selftests/bpf/prog_tests/kfunc_call.c | 36 +++++++++++++++++++ .../bpf/progs/kfunc_call_destructive.c | 14 ++++++++ 3 files changed, 55 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/kfunc_call_destructive.c diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index cbc9cd5058cb..afa7125252f6 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -695,6 +695,10 @@ noinline void bpf_kfunc_call_test_ref(struct prog_test_ref_kfunc *p) { } +noinline void bpf_kfunc_call_test_destructive(void) +{ +} + __diag_pop(); ALLOW_ERROR_INJECTION(bpf_modify_return_test, ERRNO); @@ -719,6 +723,7 @@ BTF_ID_FLAGS(func, bpf_kfunc_call_test_mem_len_pass1) BTF_ID_FLAGS(func, bpf_kfunc_call_test_mem_len_fail1) BTF_ID_FLAGS(func, bpf_kfunc_call_test_mem_len_fail2) BTF_ID_FLAGS(func, bpf_kfunc_call_test_ref, KF_TRUSTED_ARGS) +BTF_ID_FLAGS(func, bpf_kfunc_call_test_destructive, KF_DESTRUCTIVE) BTF_SET8_END(test_sk_check_kfunc_ids) static void *bpf_test_init(const union bpf_attr *kattr, u32 user_size, diff --git a/tools/testing/selftests/bpf/prog_tests/kfunc_call.c b/tools/testing/selftests/bpf/prog_tests/kfunc_call.c index c00eb974eb85..351fafa006fb 100644 --- a/tools/testing/selftests/bpf/prog_tests/kfunc_call.c +++ b/tools/testing/selftests/bpf/prog_tests/kfunc_call.c @@ -5,6 +5,9 @@ #include "kfunc_call_test.lskel.h" #include "kfunc_call_test_subprog.skel.h" #include "kfunc_call_test_subprog.lskel.h" +#include "kfunc_call_destructive.skel.h" + +#include "cap_helpers.h" static void test_main(void) { @@ -86,6 +89,36 @@ static void test_subprog_lskel(void) kfunc_call_test_subprog_lskel__destroy(skel); } +static int test_destructive_open_and_load(void) +{ + struct kfunc_call_destructive *skel; + int err; + + skel = kfunc_call_destructive__open(); + if (!ASSERT_OK_PTR(skel, "prog_open")) + return -1; + + err = kfunc_call_destructive__load(skel); + + kfunc_call_destructive__destroy(skel); + + return err; +} + +static void test_destructive(void) +{ + __u64 save_caps = 0; + + ASSERT_OK(test_destructive_open_and_load(), "succesful_load"); + + if (!ASSERT_OK(cap_disable_effective(1ULL << CAP_SYS_BOOT, &save_caps), "drop_caps")) + return; + + ASSERT_EQ(test_destructive_open_and_load(), -13, "no_caps_failure"); + + cap_enable_effective(save_caps, NULL); +} + void test_kfunc_call(void) { if (test__start_subtest("main")) @@ -96,4 +129,7 @@ void test_kfunc_call(void) if (test__start_subtest("subprog_lskel")) test_subprog_lskel(); + + if (test__start_subtest("destructive")) + test_destructive(); } diff --git a/tools/testing/selftests/bpf/progs/kfunc_call_destructive.c b/tools/testing/selftests/bpf/progs/kfunc_call_destructive.c new file mode 100644 index 000000000000..767472bc5a97 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/kfunc_call_destructive.c @@ -0,0 +1,14 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include + +extern void bpf_kfunc_call_test_destructive(void) __ksym; + +SEC("tc") +int kfunc_destructive_test(void) +{ + bpf_kfunc_call_test_destructive(); + return 0; +} + +char _license[] SEC("license") = "GPL";