From patchwork Fri Aug 11 02:36:46 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yafang Shao X-Patchwork-Id: 13350018 X-Patchwork-Delegate: bpf@iogearbox.net Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9E16DA56 for ; Fri, 11 Aug 2023 02:36:53 +0000 (UTC) Received: from mail-pl1-x633.google.com (mail-pl1-x633.google.com [IPv6:2607:f8b0:4864:20::633]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D6C4C171D for ; Thu, 10 Aug 2023 19:36:52 -0700 (PDT) Received: by mail-pl1-x633.google.com with SMTP id d9443c01a7336-1bc73a2b0easo12202055ad.0 for ; Thu, 10 Aug 2023 19:36:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1691721412; x=1692326212; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=aAkB65ONeLsMWB23KHwLn60dL+jIuhAkmjChTCR+Vjg=; b=i558YXIcAN5tpSNbhZU+v56V5h5KiWAkglcv+rEyLXB5FjKHAioL/cGc30wgsapWuZ eZoLCj49e6Xi9E2tvp/YHrkit6r8smHcIntAq0pMhaVCpmdQ+w/YDY5A44GD8319GOzv PufUinG3mr54Ku0vB1rvPY3uBqnWTv/0yIOfZ6+MTYDgvxNQU0RzA1mcWuSO7SJxfHc1 UD1BgVsSVaE7IEgb/m36CZUQQAz+ZDqkTPwAOzehaxwlrVsz/hGVRvkDNyWSzCT28FEl 1v1fuXq52U9NRh74KhQAe6X/G88Erk2B+Fzronr7pt7WZZyufzUIeErUxoeptPV40iHs dUeg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691721412; x=1692326212; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=aAkB65ONeLsMWB23KHwLn60dL+jIuhAkmjChTCR+Vjg=; b=WkugsOQGBqwyrCepCNWT2kBjYVx5i9uUF98i10YyUN4nPqG8OjNP+KRkudTObC5ZpG TDvAAA1GIaiNtL4D3+c5QfVxVdVSEJmujjOlw/zBTAlF+rk4Zs/1fjnUMjMUTvRKI7IU tr60L+Ya0TrlZDXs5mjdVKwIKL4PiuUFpaG4F+slAwMryK8rUblrvwYJ2QKpaiVD2uf2 bKuw6qSEB+9zggeBJHOrfDrxewH1ugc/L6h9FxycsGt0wx6H2goE24ej/L6QExWI3QbD 6Fcn5m9rjKFgHL+GCZzNZvRe9K4kUXdVptMlqHWXYCXJq6y1vRb3AnlpI8pjmrz/ri/m M+6Q== X-Gm-Message-State: AOJu0Ywoj9fS+5Rnp8JmcN/J6BXol6TGCEvoKT3QgNOCunaHO4Pky7rZ pfa6iz2x8muGgZmNGTZQ6Fb9XFw5KXADWA== X-Google-Smtp-Source: AGHT+IG9R2lSpVPvHVHkJsvsGSBGYFUYtPfBToK9qCm5EEyOPDJtrwxZX7pECTxeM0wbyQC9CUBoDg== X-Received: by 2002:a17:902:b58f:b0:1bb:c7e1:b43 with SMTP id a15-20020a170902b58f00b001bbc7e10b43mr532233pls.14.1691721412223; Thu, 10 Aug 2023 19:36:52 -0700 (PDT) Received: from vultr.guest ([2001:19f0:ac02:925:5400:4ff:fe89:58d6]) by smtp.gmail.com with ESMTPSA id ju17-20020a170903429100b001bdb0483e65sm1038304plb.265.2023.08.10.19.36.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 10 Aug 2023 19:36:51 -0700 (PDT) From: Yafang Shao To: ast@kernel.org, daniel@iogearbox.net, john.fastabend@gmail.com, andrii@kernel.org, martin.lau@linux.dev, song@kernel.org, yonghong.song@linux.dev, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org Cc: bpf@vger.kernel.org, Yafang Shao , Dan Carpenter Subject: [PATCH bpf-next v5 1/2] bpf: Fix uninitialized symbol in bpf_perf_link_fill_kprobe() Date: Fri, 11 Aug 2023 02:36:46 +0000 Message-Id: <20230811023647.3711-2-laoar.shao@gmail.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20230811023647.3711-1-laoar.shao@gmail.com> References: <20230811023647.3711-1-laoar.shao@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM, RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: bpf@iogearbox.net The patch 1b715e1b0ec5: "bpf: Support ->fill_link_info for perf_event" from Jul 9, 2023, leads to the following Smatch static checker warning: kernel/bpf/syscall.c:3416 bpf_perf_link_fill_kprobe() error: uninitialized symbol 'type'. That can happens when uname is NULL. So fix it by verifying the uname when we really need to fill it. Fixes: 1b715e1b0ec5 ("bpf: Support ->fill_link_info for perf_event") Reported-by: Dan Carpenter Closes: https://lore.kernel.org/bpf/85697a7e-f897-4f74-8b43-82721bebc462@kili.mountain/ Signed-off-by: Yafang Shao Acked-by: Yonghong Song Acked-by: Jiri Olsa --- kernel/bpf/syscall.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 7f4e8c3..166390f 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -3378,14 +3378,14 @@ static int bpf_perf_link_fill_common(const struct perf_event *event, if (!ulen ^ !uname) return -EINVAL; - if (!uname) - return 0; err = bpf_get_perf_event_info(event, &prog_id, fd_type, &buf, probe_offset, probe_addr); if (err) return err; + if (!uname) + return 0; if (buf) { len = strlen(buf); err = bpf_copy_to_user(uname, buf, ulen, len); From patchwork Fri Aug 11 02:36:47 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yafang Shao X-Patchwork-Id: 13350019 X-Patchwork-Delegate: bpf@iogearbox.net Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E8FEDEA9 for ; Fri, 11 Aug 2023 02:36:55 +0000 (UTC) Received: from mail-pg1-x530.google.com (mail-pg1-x530.google.com [IPv6:2607:f8b0:4864:20::530]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4411F171D for ; Thu, 10 Aug 2023 19:36:54 -0700 (PDT) Received: by mail-pg1-x530.google.com with SMTP id 41be03b00d2f7-563f752774fso1014598a12.1 for ; Thu, 10 Aug 2023 19:36:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1691721414; x=1692326214; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=txHdwRA6CmFO169hbAMxW9lYuqVfmYVhpA70RC0DeFg=; b=iaPh6NQlo5ehWihyDc/usuWb6fDuYFMU2u+UIHfnQ4pAcLlWYsxjTGmN81+B9IRtpK d8XtOZT1T38omBv4ULLMmYcXhvEaixQlDl5OYsAdSqnsxxUtDnjP0rIK2ggqE2PXEf08 JRW6m9LHys9fWi2icuTDSIHbKUlzroDLxxrVEI8+RAlP9PBFr/wdWB/1iWuvUEQ1RN4f 2liARaUFZgS7YkJuUhYBR/C5NVgThVXwfWI8cknj/NEXuigl8eS6Gmjx9G9/JRlC8hNy 4uI8nlGS15E+j7UnM47Q6C622AhtHRH9tJmgBXTLd+QuiXXHeZDWMPm688aesS+8bcSF j8pw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1691721414; x=1692326214; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=txHdwRA6CmFO169hbAMxW9lYuqVfmYVhpA70RC0DeFg=; b=I7twRQkrK3ruklu5eECX6jJhcX769WIdllrpdAa6j6oD1dXTXHKRpLUv87bJbSd1Kn vboWJQ+oJkv/3IPKsz+cVvhfbFRelekd6rF/smgJeF7ntjnYwg6h+AheXe0eZKAWPxcy 2EHykZYdq9t2jCftn1NEiV5o3YE0cczyseJejmUWHf63dwBlQTNgc9Wp+q5engPHPlQa GRF7CXn5RTXmyWfHiMtdNUBOoA0HEgsamzLvw7WWBNjBiP+5NVcZvIjIocrBwgFG2Ge8 fBKyXSkBg++8w48qnZViKPN7lNibxr/xZwweHYh+OX5IGnyMeQpCJe+VJAeuCLCQarWU 8jUg== X-Gm-Message-State: AOJu0YyBM5lL4+S/uxcIRvG2GeNHjU5km7I41AIpUSNYeedaoR9X0YMI Snw5kfy8N8FN0fhXX+Mr8+I= X-Google-Smtp-Source: AGHT+IHmOXm0LhLYvkstQkjENHNWjglYKcLIz9K/x6ZziObYyV1LKzQr0aKpOngkBI5LXZVysRniSg== X-Received: by 2002:a05:6a20:5499:b0:11f:2714:f6f3 with SMTP id i25-20020a056a20549900b0011f2714f6f3mr913541pzk.11.1691721413626; Thu, 10 Aug 2023 19:36:53 -0700 (PDT) Received: from vultr.guest ([2001:19f0:ac02:925:5400:4ff:fe89:58d6]) by smtp.gmail.com with ESMTPSA id ju17-20020a170903429100b001bdb0483e65sm1038304plb.265.2023.08.10.19.36.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 10 Aug 2023 19:36:53 -0700 (PDT) From: Yafang Shao To: ast@kernel.org, daniel@iogearbox.net, john.fastabend@gmail.com, andrii@kernel.org, martin.lau@linux.dev, song@kernel.org, yonghong.song@linux.dev, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org Cc: bpf@vger.kernel.org, Yafang Shao Subject: [PATCH bpf-next v5 2/2] selftests/bpf: Add selftest for fill_link_info Date: Fri, 11 Aug 2023 02:36:47 +0000 Message-Id: <20230811023647.3711-3-laoar.shao@gmail.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20230811023647.3711-1-laoar.shao@gmail.com> References: <20230811023647.3711-1-laoar.shao@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: bpf@iogearbox.net Add selftest for the fill_link_info of uprobe, kprobe and tracepoint. The result: $ tools/testing/selftests/bpf/test_progs --name=fill_link_info #79/1 fill_link_info/kprobe_link_info:OK #79/2 fill_link_info/kretprobe_link_info:OK #79/3 fill_link_info/kprobe_invalid_ubuff:OK #79/4 fill_link_info/tracepoint_link_info:OK #79/5 fill_link_info/uprobe_link_info:OK #79/6 fill_link_info/uretprobe_link_info:OK #79/7 fill_link_info/kprobe_multi_link_info:OK #79/8 fill_link_info/kretprobe_multi_link_info:OK #79/9 fill_link_info/kprobe_multi_invalid_ubuff:OK #79 fill_link_info:OK Summary: 1/9 PASSED, 0 SKIPPED, 0 FAILED The test case for kprobe_multi won't be run on aarch64, as it is not supported. Signed-off-by: Yafang Shao Acked-by: Yonghong Song Acked-by: Jiri Olsa --- tools/testing/selftests/bpf/DENYLIST.aarch64 | 3 + .../selftests/bpf/prog_tests/fill_link_info.c | 342 +++++++++++++++++++++ .../selftests/bpf/progs/test_fill_link_info.c | 42 +++ 3 files changed, 387 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/fill_link_info.c create mode 100644 tools/testing/selftests/bpf/progs/test_fill_link_info.c diff --git a/tools/testing/selftests/bpf/DENYLIST.aarch64 b/tools/testing/selftests/bpf/DENYLIST.aarch64 index 3b61e8b..b2f46b6 100644 --- a/tools/testing/selftests/bpf/DENYLIST.aarch64 +++ b/tools/testing/selftests/bpf/DENYLIST.aarch64 @@ -12,3 +12,6 @@ kprobe_multi_test/skel_api # libbpf: failed to load BPF sk module_attach # prog 'kprobe_multi': failed to auto-attach: -95 fentry_test/fentry_many_args # fentry_many_args:FAIL:fentry_many_args_attach unexpected error: -524 fexit_test/fexit_many_args # fexit_many_args:FAIL:fexit_many_args_attach unexpected error: -524 +fill_link_info/kprobe_multi_link_info # bpf_program__attach_kprobe_multi_opts unexpected error: -95 +fill_link_info/kretprobe_multi_link_info # bpf_program__attach_kprobe_multi_opts unexpected error: -95 +fill_link_info/kprobe_multi_ubuff # bpf_program__attach_kprobe_multi_opts unexpected error: -95 diff --git a/tools/testing/selftests/bpf/prog_tests/fill_link_info.c b/tools/testing/selftests/bpf/prog_tests/fill_link_info.c new file mode 100644 index 0000000..9d768e0 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/fill_link_info.c @@ -0,0 +1,342 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2023 Yafang Shao */ + +#include +#include +#include +#include +#include "trace_helpers.h" +#include "test_fill_link_info.skel.h" + +#define TP_CAT "sched" +#define TP_NAME "sched_switch" + +static const char *kmulti_syms[] = { + "bpf_fentry_test2", + "bpf_fentry_test1", + "bpf_fentry_test3", +}; +#define KMULTI_CNT ARRAY_SIZE(kmulti_syms) +static __u64 kmulti_addrs[KMULTI_CNT]; + +#define KPROBE_FUNC "bpf_fentry_test1" +static __u64 kprobe_addr; + +#define UPROBE_FILE "/proc/self/exe" +static ssize_t uprobe_offset; +/* uprobe attach point */ +static noinline void uprobe_func(void) +{ + asm volatile (""); +} + +static int verify_perf_link_info(int fd, enum bpf_perf_event_type type, long addr, + ssize_t offset, ssize_t entry_offset) +{ + struct bpf_link_info info; + __u32 len = sizeof(info); + char buf[PATH_MAX]; + int err; + + memset(&info, 0, sizeof(info)); + buf[0] = '\0'; + +again: + err = bpf_link_get_info_by_fd(fd, &info, &len); + if (!ASSERT_OK(err, "get_link_info")) + return -1; + + if (!ASSERT_EQ(info.type, BPF_LINK_TYPE_PERF_EVENT, "link_type")) + return -1; + if (!ASSERT_EQ(info.perf_event.type, type, "perf_type_match")) + return -1; + + switch (info.perf_event.type) { + case BPF_PERF_EVENT_KPROBE: + case BPF_PERF_EVENT_KRETPROBE: + ASSERT_EQ(info.perf_event.kprobe.offset, offset, "kprobe_offset"); + + /* In case kernel.kptr_restrict is not permitted or MAX_SYMS is reached */ + if (addr) + ASSERT_EQ(info.perf_event.kprobe.addr, addr + entry_offset, + "kprobe_addr"); + + if (!info.perf_event.kprobe.func_name) { + ASSERT_EQ(info.perf_event.kprobe.name_len, 0, "name_len"); + info.perf_event.kprobe.func_name = ptr_to_u64(&buf); + info.perf_event.kprobe.name_len = sizeof(buf); + goto again; + } + + err = strncmp(u64_to_ptr(info.perf_event.kprobe.func_name), KPROBE_FUNC, + strlen(KPROBE_FUNC)); + ASSERT_EQ(err, 0, "cmp_kprobe_func_name"); + break; + case BPF_PERF_EVENT_TRACEPOINT: + if (!info.perf_event.tracepoint.tp_name) { + ASSERT_EQ(info.perf_event.tracepoint.name_len, 0, "name_len"); + info.perf_event.tracepoint.tp_name = ptr_to_u64(&buf); + info.perf_event.tracepoint.name_len = sizeof(buf); + goto again; + } + + err = strncmp(u64_to_ptr(info.perf_event.tracepoint.tp_name), TP_NAME, + strlen(TP_NAME)); + ASSERT_EQ(err, 0, "cmp_tp_name"); + break; + case BPF_PERF_EVENT_UPROBE: + case BPF_PERF_EVENT_URETPROBE: + ASSERT_EQ(info.perf_event.uprobe.offset, offset, "uprobe_offset"); + + if (!info.perf_event.uprobe.file_name) { + ASSERT_EQ(info.perf_event.uprobe.name_len, 0, "name_len"); + info.perf_event.uprobe.file_name = ptr_to_u64(&buf); + info.perf_event.uprobe.name_len = sizeof(buf); + goto again; + } + + err = strncmp(u64_to_ptr(info.perf_event.uprobe.file_name), UPROBE_FILE, + strlen(UPROBE_FILE)); + ASSERT_EQ(err, 0, "cmp_file_name"); + break; + default: + err = -1; + break; + } + return err; +} + +static void kprobe_fill_invalid_user_buffer(int fd) +{ + struct bpf_link_info info; + __u32 len = sizeof(info); + int err; + + memset(&info, 0, sizeof(info)); + + info.perf_event.kprobe.func_name = 0x1; /* invalid address */ + err = bpf_link_get_info_by_fd(fd, &info, &len); + ASSERT_EQ(err, -EINVAL, "invalid_buff_and_len"); + + info.perf_event.kprobe.name_len = 64; + err = bpf_link_get_info_by_fd(fd, &info, &len); + ASSERT_EQ(err, -EFAULT, "invalid_buff"); + + info.perf_event.kprobe.func_name = 0; + err = bpf_link_get_info_by_fd(fd, &info, &len); + ASSERT_EQ(err, -EINVAL, "invalid_len"); + + ASSERT_EQ(info.perf_event.kprobe.addr, 0, "func_addr"); + ASSERT_EQ(info.perf_event.kprobe.offset, 0, "func_offset"); + ASSERT_EQ(info.perf_event.type, 0, "type"); +} + +static void test_kprobe_fill_link_info(struct test_fill_link_info *skel, + enum bpf_perf_event_type type, + bool invalid) +{ + DECLARE_LIBBPF_OPTS(bpf_kprobe_opts, opts, + .attach_mode = PROBE_ATTACH_MODE_LINK, + .retprobe = type == BPF_PERF_EVENT_KRETPROBE, + ); + ssize_t entry_offset = 0; + int link_fd, err; + + skel->links.kprobe_run = bpf_program__attach_kprobe_opts(skel->progs.kprobe_run, + KPROBE_FUNC, &opts); + if (!ASSERT_OK_PTR(skel->links.kprobe_run, "attach_kprobe")) + return; + + link_fd = bpf_link__fd(skel->links.kprobe_run); + if (!invalid) { + /* See also arch_adjust_kprobe_addr(). */ + if (skel->kconfig->CONFIG_X86_KERNEL_IBT) + entry_offset = 4; + err = verify_perf_link_info(link_fd, type, kprobe_addr, 0, entry_offset); + ASSERT_OK(err, "verify_perf_link_info"); + } else { + kprobe_fill_invalid_user_buffer(link_fd); + } + bpf_link__detach(skel->links.kprobe_run); +} + +static void test_tp_fill_link_info(struct test_fill_link_info *skel) +{ + int link_fd, err; + + skel->links.tp_run = bpf_program__attach_tracepoint(skel->progs.tp_run, TP_CAT, TP_NAME); + if (!ASSERT_OK_PTR(skel->links.tp_run, "attach_tp")) + return; + + link_fd = bpf_link__fd(skel->links.tp_run); + err = verify_perf_link_info(link_fd, BPF_PERF_EVENT_TRACEPOINT, 0, 0, 0); + ASSERT_OK(err, "verify_perf_link_info"); + bpf_link__detach(skel->links.tp_run); +} + +static void test_uprobe_fill_link_info(struct test_fill_link_info *skel, + enum bpf_perf_event_type type) +{ + int link_fd, err; + + skel->links.uprobe_run = bpf_program__attach_uprobe(skel->progs.uprobe_run, + type == BPF_PERF_EVENT_URETPROBE, + 0, /* self pid */ + UPROBE_FILE, uprobe_offset); + if (!ASSERT_OK_PTR(skel->links.uprobe_run, "attach_uprobe")) + return; + + link_fd = bpf_link__fd(skel->links.uprobe_run); + err = verify_perf_link_info(link_fd, type, 0, uprobe_offset, 0); + ASSERT_OK(err, "verify_perf_link_info"); + bpf_link__detach(skel->links.uprobe_run); +} + +static int verify_kmulti_link_info(int fd, bool retprobe) +{ + struct bpf_link_info info; + __u32 len = sizeof(info); + __u64 addrs[KMULTI_CNT]; + int flags, i, err; + + memset(&info, 0, sizeof(info)); + +again: + err = bpf_link_get_info_by_fd(fd, &info, &len); + if (!ASSERT_OK(err, "get_link_info")) + return -1; + + if (!ASSERT_EQ(info.type, BPF_LINK_TYPE_KPROBE_MULTI, "kmulti_type")) + return -1; + + ASSERT_EQ(info.kprobe_multi.count, KMULTI_CNT, "func_cnt"); + flags = info.kprobe_multi.flags & BPF_F_KPROBE_MULTI_RETURN; + if (!retprobe) + ASSERT_EQ(flags, 0, "kmulti_flags"); + else + ASSERT_NEQ(flags, 0, "kretmulti_flags"); + + if (!info.kprobe_multi.addrs) { + info.kprobe_multi.addrs = ptr_to_u64(addrs); + goto again; + } + for (i = 0; i < KMULTI_CNT; i++) + ASSERT_EQ(addrs[i], kmulti_addrs[i], "kmulti_addrs"); + return 0; +} + +static void verify_kmulti_invalid_user_buffer(int fd) +{ + struct bpf_link_info info; + __u32 len = sizeof(info); + __u64 addrs[KMULTI_CNT]; + int err, i; + + memset(&info, 0, sizeof(info)); + + info.kprobe_multi.count = KMULTI_CNT; + err = bpf_link_get_info_by_fd(fd, &info, &len); + ASSERT_EQ(err, -EINVAL, "no_addr"); + + info.kprobe_multi.addrs = ptr_to_u64(addrs); + info.kprobe_multi.count = 0; + err = bpf_link_get_info_by_fd(fd, &info, &len); + ASSERT_EQ(err, -EINVAL, "no_cnt"); + + for (i = 0; i < KMULTI_CNT; i++) + addrs[i] = 0; + info.kprobe_multi.count = KMULTI_CNT - 1; + err = bpf_link_get_info_by_fd(fd, &info, &len); + ASSERT_EQ(err, -ENOSPC, "smaller_cnt"); + for (i = 0; i < KMULTI_CNT - 1; i++) + ASSERT_EQ(addrs[i], kmulti_addrs[i], "kmulti_addrs"); + ASSERT_EQ(addrs[i], 0, "kmulti_addrs"); + + for (i = 0; i < KMULTI_CNT; i++) + addrs[i] = 0; + info.kprobe_multi.count = KMULTI_CNT + 1; + err = bpf_link_get_info_by_fd(fd, &info, &len); + ASSERT_EQ(err, 0, "bigger_cnt"); + for (i = 0; i < KMULTI_CNT; i++) + ASSERT_EQ(addrs[i], kmulti_addrs[i], "kmulti_addrs"); + + info.kprobe_multi.count = KMULTI_CNT; + info.kprobe_multi.addrs = 0x1; /* invalid addr */ + err = bpf_link_get_info_by_fd(fd, &info, &len); + ASSERT_EQ(err, -EFAULT, "invalid_buff"); +} + +static int symbols_cmp_r(const void *a, const void *b) +{ + const char **str_a = (const char **) a; + const char **str_b = (const char **) b; + + return strcmp(*str_a, *str_b); +} + +static void test_kprobe_multi_fill_link_info(struct test_fill_link_info *skel, + bool retprobe, bool invalid) +{ + LIBBPF_OPTS(bpf_kprobe_multi_opts, opts); + int link_fd, err; + + opts.syms = kmulti_syms; + opts.cnt = KMULTI_CNT; + opts.retprobe = retprobe; + skel->links.kmulti_run = bpf_program__attach_kprobe_multi_opts(skel->progs.kmulti_run, + NULL, &opts); + if (!ASSERT_OK_PTR(skel->links.kmulti_run, "attach_kprobe_multi")) + return; + + link_fd = bpf_link__fd(skel->links.kmulti_run); + if (!invalid) { + err = verify_kmulti_link_info(link_fd, retprobe); + ASSERT_OK(err, "verify_kmulti_link_info"); + } else { + verify_kmulti_invalid_user_buffer(link_fd); + } + bpf_link__detach(skel->links.kmulti_run); +} + +void test_fill_link_info(void) +{ + struct test_fill_link_info *skel; + int i; + + skel = test_fill_link_info__open_and_load(); + if (!ASSERT_OK_PTR(skel, "skel_open")) + return; + + /* load kallsyms to compare the addr */ + if (!ASSERT_OK(load_kallsyms_refresh(), "load_kallsyms_refresh")) + goto cleanup; + + kprobe_addr = ksym_get_addr(KPROBE_FUNC); + if (test__start_subtest("kprobe_link_info")) + test_kprobe_fill_link_info(skel, BPF_PERF_EVENT_KPROBE, false); + if (test__start_subtest("kretprobe_link_info")) + test_kprobe_fill_link_info(skel, BPF_PERF_EVENT_KRETPROBE, false); + if (test__start_subtest("kprobe_invalid_ubuff")) + test_kprobe_fill_link_info(skel, BPF_PERF_EVENT_KPROBE, true); + if (test__start_subtest("tracepoint_link_info")) + test_tp_fill_link_info(skel); + + uprobe_offset = get_uprobe_offset(&uprobe_func); + if (test__start_subtest("uprobe_link_info")) + test_uprobe_fill_link_info(skel, BPF_PERF_EVENT_UPROBE); + if (test__start_subtest("uretprobe_link_info")) + test_uprobe_fill_link_info(skel, BPF_PERF_EVENT_URETPROBE); + + qsort(kmulti_syms, KMULTI_CNT, sizeof(kmulti_syms[0]), symbols_cmp_r); + for (i = 0; i < KMULTI_CNT; i++) + kmulti_addrs[i] = ksym_get_addr(kmulti_syms[i]); + if (test__start_subtest("kprobe_multi_link_info")) + test_kprobe_multi_fill_link_info(skel, false, false); + if (test__start_subtest("kretprobe_multi_link_info")) + test_kprobe_multi_fill_link_info(skel, true, false); + if (test__start_subtest("kprobe_multi_invalid_ubuff")) + test_kprobe_multi_fill_link_info(skel, true, true); + +cleanup: + test_fill_link_info__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/test_fill_link_info.c b/tools/testing/selftests/bpf/progs/test_fill_link_info.c new file mode 100644 index 0000000..564f402 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_fill_link_info.c @@ -0,0 +1,42 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2023 Yafang Shao */ + +#include "vmlinux.h" +#include +#include + +extern bool CONFIG_X86_KERNEL_IBT __kconfig __weak; + +/* This function is here to have CONFIG_X86_KERNEL_IBT + * used and added to object BTF. + */ +int unused(void) +{ + return CONFIG_X86_KERNEL_IBT ? 0 : 1; +} + +SEC("kprobe") +int BPF_PROG(kprobe_run) +{ + return 0; +} + +SEC("uprobe") +int BPF_PROG(uprobe_run) +{ + return 0; +} + +SEC("tracepoint") +int BPF_PROG(tp_run) +{ + return 0; +} + +SEC("kprobe.multi") +int BPF_PROG(kmulti_run) +{ + return 0; +} + +char _license[] SEC("license") = "GPL";