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=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham 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 B5D5AC2D0CE for ; Tue, 21 Jan 2020 12:05:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8C11C24125 for ; Tue, 21 Jan 2020 12:05:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579608338; bh=Oc19Vg9TpXp44tut/R0V7WO+E7uN3DT2JpxtV2y9qlM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=tq4+frbTZ3l2VOMfnrmM1YG5j2btV3TnuFgxsoaBzkBtdcw0U1pgRWJ9P6NL+NqOc Rdn3oj+DHVVIMtqwu+O/udVWgYiNvtiwQMW2221Vv6Xas7Yakwrg0G1nivyfcumGqb S5XGJznRhb04CDZxydx0cIv9jMSnjsYps5nLCFLE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729431AbgAUMFi convert rfc822-to-8bit (ORCPT ); Tue, 21 Jan 2020 07:05:38 -0500 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:60243 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729541AbgAUMFi (ORCPT ); Tue, 21 Jan 2020 07:05:38 -0500 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-383--M6epoTONQa3a_K_FXLkhA-1; Tue, 21 Jan 2020 07:05:33 -0500 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id AD88CDB60; Tue, 21 Jan 2020 12:05:31 +0000 (UTC) Received: from krava.redhat.com (unknown [10.43.17.48]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5AFB85C28D; Tue, 21 Jan 2020 12:05:29 +0000 (UTC) From: Jiri Olsa To: Alexei Starovoitov , Daniel Borkmann Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, Andrii Nakryiko , Yonghong Song , Martin KaFai Lau , Jakub Kicinski , David Miller , =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= , John Fastabend Subject: [PATCH 6/6] selftest/bpf: Add test for allowed trampolines count Date: Tue, 21 Jan 2020 13:05:12 +0100 Message-Id: <20200121120512.758929-7-jolsa@kernel.org> In-Reply-To: <20200121120512.758929-1-jolsa@kernel.org> References: <20200121120512.758929-1-jolsa@kernel.org> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-MC-Unique: -M6epoTONQa3a_K_FXLkhA-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kernel.org Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: 8BIT Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org There's limit of 40 programs tht can be attached to trampoline for one function. Adding test that tries to attach that many plus one extra that needs to fail. Signed-off-by: Jiri Olsa --- .../bpf/prog_tests/trampoline_count.c | 112 ++++++++++++++++++ .../bpf/progs/test_trampoline_count.c | 21 ++++ 2 files changed, 133 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/trampoline_count.c create mode 100644 tools/testing/selftests/bpf/progs/test_trampoline_count.c diff --git a/tools/testing/selftests/bpf/prog_tests/trampoline_count.c b/tools/testing/selftests/bpf/prog_tests/trampoline_count.c new file mode 100644 index 000000000000..1235f3d1cc50 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/trampoline_count.c @@ -0,0 +1,112 @@ +// SPDX-License-Identifier: GPL-2.0-only +#define _GNU_SOURCE +#include +#include +#include + +#define MAX_TRAMP_PROGS 40 + +struct inst { + struct bpf_object *obj; + struct bpf_link *link_fentry; + struct bpf_link *link_fexit; +}; + +static int test_task_rename(void) +{ + int fd, duration = 0, err; + char buf[] = "test_overhead"; + + fd = open("/proc/self/comm", O_WRONLY|O_TRUNC); + if (CHECK(fd < 0, "open /proc", "err %d", errno)) + return -1; + err = write(fd, buf, sizeof(buf)); + if (err < 0) { + CHECK(err < 0, "task rename", "err %d", errno); + close(fd); + return -1; + } + close(fd); + return 0; +} + +static struct bpf_link *load(struct bpf_object *obj, const char *name) +{ + struct bpf_program *prog; + int duration = 0; + + prog = bpf_object__find_program_by_title(obj, name); + if (CHECK(!prog, "find_probe", "prog '%s' not found\n", name)) + return ERR_PTR(-EINVAL); + return bpf_program__attach_trace(prog); +} + +void test_trampoline_count(void) +{ + const char *fentry_name = "fentry/__set_task_comm"; + const char *fexit_name = "fexit/__set_task_comm"; + const char *object = "test_trampoline_count.o"; + struct inst inst[MAX_TRAMP_PROGS] = { 0 }; + int err, i = 0, duration = 0; + struct bpf_object *obj; + struct bpf_link *link; + char comm[16] = {}; + + /* attach 'allowed' 40 trampoline programs */ + for (i = 0; i < MAX_TRAMP_PROGS; i++) { + obj = bpf_object__open_file(object, NULL); + if (CHECK(IS_ERR(obj), "obj_open_file", "err %ld\n", PTR_ERR(obj))) + goto cleanup; + + err = bpf_object__load(obj); + if (CHECK(err, "obj_load", "err %d\n", err)) + goto cleanup; + inst[i].obj = obj; + + if (rand() % 2) { + link = load(obj, fentry_name); + if (CHECK(IS_ERR(link), "attach prog", "err %ld\n", PTR_ERR(link))) + goto cleanup; + inst[i].link_fentry = link; + } else { + link = load(obj, fexit_name); + if (CHECK(IS_ERR(link), "attach prog", "err %ld\n", PTR_ERR(link))) + goto cleanup; + inst[i].link_fexit = link; + } + } + + /* and try 1 extra.. */ + obj = bpf_object__open_file(object, NULL); + if (CHECK(IS_ERR(obj), "obj_open_file", "err %ld\n", PTR_ERR(obj))) + goto cleanup; + + err = bpf_object__load(obj); + if (CHECK(err, "obj_load", "err %d\n", err)) + goto cleanup_extra; + + /* ..that needs to fail */ + link = load(obj, fentry_name); + if (CHECK(!IS_ERR(link), "cannot attach over the limit", "err %ld\n", PTR_ERR(link))) { + bpf_link__destroy(link); + goto cleanup_extra; + } + + /* with E2BIG error */ + CHECK(PTR_ERR(link) != -E2BIG, "proper error check", "err %ld\n", PTR_ERR(link)); + + /* and finaly execute the probe */ + if (CHECK_FAIL(prctl(PR_GET_NAME, comm, 0L, 0L, 0L))) + goto cleanup_extra; + CHECK_FAIL(test_task_rename()); + CHECK_FAIL(prctl(PR_SET_NAME, comm, 0L, 0L, 0L)); + +cleanup_extra: + bpf_object__close(obj); +cleanup: + while (--i) { + bpf_link__destroy(inst[i].link_fentry); + bpf_link__destroy(inst[i].link_fexit); + bpf_object__close(inst[i].obj); + } +} diff --git a/tools/testing/selftests/bpf/progs/test_trampoline_count.c b/tools/testing/selftests/bpf/progs/test_trampoline_count.c new file mode 100644 index 000000000000..e51e6e3a81c2 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_trampoline_count.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include "bpf_trace_helpers.h" + +struct task_struct; + +SEC("fentry/__set_task_comm") +int BPF_PROG(prog1, struct task_struct *tsk, const char *buf, bool exec) +{ + return 0; +} + +SEC("fexit/__set_task_comm") +int BPF_PROG(prog2, struct task_struct *tsk, const char *buf, bool exec) +{ + return 0; +} + +char _license[] SEC("license") = "GPL"; -- 2.24.1