From patchwork Fri Feb 4 00:55:19 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matteo Croce X-Patchwork-Id: 12734743 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 E01A6C433EF for ; Fri, 4 Feb 2022 00:55:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356322AbiBDAzo (ORCPT ); Thu, 3 Feb 2022 19:55:44 -0500 Received: from mail-wr1-f48.google.com ([209.85.221.48]:41494 "EHLO mail-wr1-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1356316AbiBDAzn (ORCPT ); Thu, 3 Feb 2022 19:55:43 -0500 Received: by mail-wr1-f48.google.com with SMTP id j16so8240033wrd.8; Thu, 03 Feb 2022 16:55:43 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=kU7g6tMkpTj/AU6TPU7JxrwuE+kJFMbSckL9QL5y1sU=; b=CfLkkVekrqcfQk26cIQ1Dv9Qzr+8NC16IUlXGGZxR9duwsfygShQiz7Gyn3oCcIcjh WsZ1crzXJBevtbQXXEpFbP3aIU35Xmn4BoYd6vjzxEjZMMiOplqyY9IzulJ9XCnvf/vS hgsTDa/nCT3zu+nfCnH9mWeTQICqlJeWVJNYp3aVGpLw1pm5YZCX3xcGdmE7okvgXRPB szeaJi6O/2CQY6X4iQPkD2bWaak9ROFzho6Eg2AmzjezzCNhhkkTMZ2kkaMSWF2xA7Ou TrkOORY24REw65mcMPWifPTfaXuacdwXkGQZeCWYE9IZCe1l7FmGZQxQj32IS433RO9h tv/g== X-Gm-Message-State: AOAM531XXtrGFwJkN7YCRR5i42xbx+2PLgoiqv0mtMzR+xJqO5WJV92v 0Wxr53Xo1dII3HxDQqnYas8= X-Google-Smtp-Source: ABdhPJzUphLNSqiWTFVE+GQLHIt9Jj+F9GZyf0Xlq3ZdZ6955J1HL85BRrSGwqzrhWn9SGXQRHkzwQ== X-Received: by 2002:adf:f90c:: with SMTP id b12mr372663wrr.97.1643936142393; Thu, 03 Feb 2022 16:55:42 -0800 (PST) Received: from t490s.teknoraver.net (net-2-35-22-35.cust.vodafonedsl.it. [2.35.22.35]) by smtp.gmail.com with ESMTPSA id c8sm240391wmq.34.2022.02.03.16.55.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 03 Feb 2022 16:55:41 -0800 (PST) From: Matteo Croce To: Alexei Starovoitov , bpf@vger.kernel.org Cc: Daniel Borkmann , Andrii Nakryiko , linux-kernel@vger.kernel.org Subject: [PATCH bpf-next v3 2/2] selftests/bpf: test maximum recursion depth for bpf_core_types_are_compat() Date: Fri, 4 Feb 2022 01:55:19 +0100 Message-Id: <20220204005519.60361-3-mcroce@linux.microsoft.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220204005519.60361-1-mcroce@linux.microsoft.com> References: <20220204005519.60361-1-mcroce@linux.microsoft.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net From: Matteo Croce bpf_core_types_are_compat() was limited to 2 recursion levels, which are enough to parse a function prototype. Add a test which checks the existence of a function prototype, so to test the bpf_core_types_are_compat() code path. The test for the recursion limit being hit is done in a separate object, because the kernel failure makes the whole load to fail. Sample run log with extra prints: [ 5689.913751] bpf_core_apply_relo_insn:1200 cands->len: 2 [ 5689.913902] bpf_core_types_are_compat:6896: ret: 1 [ 5689.913994] bpf_core_types_are_compat:6896: ret: 0 [ 5689.914025] bpf_core_apply_relo_insn:1200 cands->len: 2 [ 5689.914141] bpf_core_types_are_compat:6896: ret: 0 [ 5689.914246] bpf_core_types_are_compat:6896: ret: 0 test_core_kern_lskel:PASS:open_and_load 0 nsec test_core_kern_lskel:PASS:attach(core_relo_proto) 0 nsec test_core_kern_lskel:PASS:bpf_core_type_exists 0 nsec test_core_kern_lskel:PASS:!bpf_core_type_exists 0 nsec #41 core_kern_lskel:OK [ 5689.915267] bpf_core_apply_relo_insn:1200 cands->len: 2 [ 5689.915399] bpf_core_types_are_compat:6896: ret: 0 [ 5689.915504] bpf_core_types_are_compat:6896: ret: -22 test_core_kern_overflow_lskel:PASS:open_and_load 0 nsec #42 core_kern_overflow_lskel:OK Summary: 2/0 PASSED, 0 SKIPPED, 0 FAILED Successfully unloaded bpf_testmod.ko. Signed-off-by: Matteo Croce --- tools/testing/selftests/bpf/Makefile | 2 +- .../selftests/bpf/bpf_testmod/bpf_testmod.c | 5 +++++ .../selftests/bpf/prog_tests/core_kern.c | 15 ++++++++++++- .../bpf/prog_tests/core_kern_overflow.c | 13 ++++++++++++ tools/testing/selftests/bpf/progs/core_kern.c | 14 +++++++++++++ .../selftests/bpf/progs/core_kern_overflow.c | 21 +++++++++++++++++++ 6 files changed, 68 insertions(+), 2 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/core_kern_overflow.c create mode 100644 tools/testing/selftests/bpf/progs/core_kern_overflow.c diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 945f92d71db3..91ea729990da 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -330,7 +330,7 @@ LINKED_SKELS := test_static_linked.skel.h linked_funcs.skel.h \ LSKELS := kfunc_call_test.c fentry_test.c fexit_test.c fexit_sleep.c \ test_ringbuf.c atomics.c trace_printk.c trace_vprintk.c \ - map_ptr_kern.c core_kern.c + map_ptr_kern.c core_kern.c core_kern_overflow.c # Generate both light skeleton and libbpf skeleton for these LSKELS_EXTRA := test_ksyms_module.c test_ksyms_weak.c kfunc_call_test_subprog.c SKEL_BLACKLIST += $$(LSKELS) diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c index 595d32ab285a..e5ba8d8a17da 100644 --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c @@ -13,6 +13,11 @@ #define CREATE_TRACE_POINTS #include "bpf_testmod-events.h" +typedef int (*func_proto_typedef___match)(long); +typedef int (*func_proto_typedef___overflow)(func_proto_typedef___match); +func_proto_typedef___match funcp = NULL; +func_proto_typedef___overflow funcp_of = NULL; + DEFINE_PER_CPU(int, bpf_testmod_ksym_percpu) = 123; noinline void diff --git a/tools/testing/selftests/bpf/prog_tests/core_kern.c b/tools/testing/selftests/bpf/prog_tests/core_kern.c index 561c5185d886..91493f5836ff 100644 --- a/tools/testing/selftests/bpf/prog_tests/core_kern.c +++ b/tools/testing/selftests/bpf/prog_tests/core_kern.c @@ -7,8 +7,21 @@ void test_core_kern_lskel(void) { struct core_kern_lskel *skel; + int link_fd; skel = core_kern_lskel__open_and_load(); - ASSERT_OK_PTR(skel, "open_and_load"); + if (!ASSERT_OK_PTR(skel, "open_and_load")) + return; + + link_fd = core_kern_lskel__core_relo_proto__attach(skel); + if (!ASSERT_GT(link_fd, 0, "attach(core_relo_proto)")) + goto cleanup; + + /* trigger tracepoints */ + usleep(1); + ASSERT_TRUE(skel->bss->proto_out[0], "bpf_core_type_exists"); + ASSERT_FALSE(skel->bss->proto_out[1], "!bpf_core_type_exists"); + +cleanup: core_kern_lskel__destroy(skel); } diff --git a/tools/testing/selftests/bpf/prog_tests/core_kern_overflow.c b/tools/testing/selftests/bpf/prog_tests/core_kern_overflow.c new file mode 100644 index 000000000000..04cc145bc26a --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/core_kern_overflow.c @@ -0,0 +1,13 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include "test_progs.h" +#include "core_kern_overflow.lskel.h" + +void test_core_kern_overflow_lskel(void) +{ + struct core_kern_overflow_lskel *skel; + + skel = core_kern_overflow_lskel__open_and_load(); + if (!ASSERT_NULL(skel, "open_and_load")) + core_kern_overflow_lskel__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/core_kern.c b/tools/testing/selftests/bpf/progs/core_kern.c index 13499cc15c7d..acabe4cb0480 100644 --- a/tools/testing/selftests/bpf/progs/core_kern.c +++ b/tools/testing/selftests/bpf/progs/core_kern.c @@ -101,4 +101,18 @@ int balancer_ingress(struct __sk_buff *ctx) return 0; } +typedef int (*func_proto_typedef___match)(long); +typedef void (*func_proto_typedef___doesnt_match)(char*); + +int proto_out[2]; + +SEC("raw_tracepoint/sys_enter") +int core_relo_proto(void *ctx) +{ + proto_out[0] = bpf_core_type_exists(func_proto_typedef___match); + proto_out[1] = bpf_core_type_exists(func_proto_typedef___doesnt_match); + + return 0; +} + char LICENSE[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/core_kern_overflow.c b/tools/testing/selftests/bpf/progs/core_kern_overflow.c new file mode 100644 index 000000000000..70417413af55 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/core_kern_overflow.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "vmlinux.h" + +#include +#include +#include + +typedef int (*func_proto_typedef___match)(long); +typedef int (*func_proto_typedef___overflow)(func_proto_typedef___match); + +int proto_out; + +SEC("raw_tracepoint/sys_enter") +int core_relo_proto(void *ctx) +{ + proto_out = bpf_core_type_exists(func_proto_typedef___overflow); + + return 0; +} + +char LICENSE[] SEC("license") = "GPL";