// SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2021 Facebook */ #define _GNU_SOURCE #include #include #include #include #include #include "test_bpf_cookie.skel.h" static void kprobe_subtest(struct test_bpf_cookie *skel) { DECLARE_LIBBPF_OPTS(bpf_kprobe_opts, opts); struct bpf_link *link1 = NULL, *link2 = NULL; struct bpf_link *retlink1 = NULL, *retlink2 = NULL; /* attach two kprobes */ opts.bpf_cookie = 0x1; opts.retprobe = false; link1 = bpf_program__attach_kprobe_opts(skel->progs.handle_kprobe, SYS_NANOSLEEP_KPROBE_NAME, &opts); if (!ASSERT_OK_PTR(link1, "link1")) goto cleanup; opts.bpf_cookie = 0x2; opts.retprobe = false; link2 = bpf_program__attach_kprobe_opts(skel->progs.handle_kprobe, SYS_NANOSLEEP_KPROBE_NAME, &opts); if (!ASSERT_OK_PTR(link2, "link2")) goto cleanup; /* attach two kretprobes */ opts.bpf_cookie = 0x10; opts.retprobe = true; retlink1 = bpf_program__attach_kprobe_opts(skel->progs.handle_kretprobe, SYS_NANOSLEEP_KPROBE_NAME, &opts); if (!ASSERT_OK_PTR(retlink1, "retlink1")) goto cleanup; opts.bpf_cookie = 0x20; opts.retprobe = true; retlink2 = bpf_program__attach_kprobe_opts(skel->progs.handle_kretprobe, SYS_NANOSLEEP_KPROBE_NAME, &opts); if (!ASSERT_OK_PTR(retlink2, "retlink2")) goto cleanup; /* trigger kprobe && kretprobe */ usleep(1); ASSERT_EQ(skel->bss->kprobe_res, 0x1 | 0x2, "kprobe_res"); ASSERT_EQ(skel->bss->kretprobe_res, 0x10 | 0x20, "kretprobe_res"); cleanup: bpf_link__destroy(link1); bpf_link__destroy(link2); bpf_link__destroy(retlink1); bpf_link__destroy(retlink2); } static void uprobe_subtest(struct test_bpf_cookie *skel) { DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, opts); struct bpf_link *link1 = NULL, *link2 = NULL; struct bpf_link *retlink1 = NULL, *retlink2 = NULL; size_t uprobe_offset; ssize_t base_addr; base_addr = get_base_addr(); uprobe_offset = get_uprobe_offset(&get_base_addr, base_addr); /* attach two uprobes */ opts.bpf_cookie = 0x100; opts.retprobe = false; link1 = bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe, 0 /* self pid */, "/proc/self/exe", uprobe_offset, &opts); if (!ASSERT_OK_PTR(link1, "link1")) goto cleanup; opts.bpf_cookie = 0x200; opts.retprobe = false; link2 = bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe, -1 /* any pid */, "/proc/self/exe", uprobe_offset, &opts); if (!ASSERT_OK_PTR(link2, "link2")) goto cleanup; /* attach two uretprobes */ opts.bpf_cookie = 0x1000; opts.retprobe = true; retlink1 = bpf_program__attach_uprobe_opts(skel->progs.handle_uretprobe, -1 /* any pid */, "/proc/self/exe", uprobe_offset, &opts); if (!ASSERT_OK_PTR(retlink1, "retlink1")) goto cleanup; opts.bpf_cookie = 0x2000; opts.retprobe = true; retlink2 = bpf_program__attach_uprobe_opts(skel->progs.handle_uretprobe, 0 /* self pid */, "/proc/self/exe", uprobe_offset, &opts); if (!ASSERT_OK_PTR(retlink2, "retlink2")) goto cleanup; /* trigger uprobe && uretprobe */ get_base_addr(); ASSERT_EQ(skel->bss->uprobe_res, 0x100 | 0x200, "uprobe_res"); ASSERT_EQ(skel->bss->uretprobe_res, 0x1000 | 0x2000, "uretprobe_res"); cleanup: bpf_link__destroy(link1); bpf_link__destroy(link2); bpf_link__destroy(retlink1); bpf_link__destroy(retlink2); } static void tp_subtest(struct test_bpf_cookie *skel) { DECLARE_LIBBPF_OPTS(bpf_tracepoint_opts, opts); struct bpf_link *link1 = NULL, *link2 = NULL, *link3 = NULL; /* attach first tp prog */ opts.bpf_cookie = 0x10000; link1 = bpf_program__attach_tracepoint_opts(skel->progs.handle_tp1, "syscalls", "sys_enter_nanosleep", &opts); if (!ASSERT_OK_PTR(link1, "link1")) goto cleanup; /* attach second tp prog */ opts.bpf_cookie = 0x20000; link2 = bpf_program__attach_tracepoint_opts(skel->progs.handle_tp2, "syscalls", "sys_enter_nanosleep", &opts); if (!ASSERT_OK_PTR(link2, "link2")) goto cleanup; /* trigger tracepoints */ usleep(1); ASSERT_EQ(skel->bss->tp_res, 0x10000 | 0x20000, "tp_res1"); /* now we detach first prog and will attach third one, which causes * two internal calls to bpf_prog_array_copy(), shuffling * bpf_prog_array_items around. We test here that we don't lose track * of associated bpf_cookies. */ bpf_link__destroy(link1); link1 = NULL; kern_sync_rcu(); skel->bss->tp_res = 0; /* attach third tp prog */ opts.bpf_cookie = 0x40000; link3 = bpf_program__attach_tracepoint_opts(skel->progs.handle_tp3, "syscalls", "sys_enter_nanosleep", &opts); if (!ASSERT_OK_PTR(link3, "link3")) goto cleanup; /* trigger tracepoints */ usleep(1); ASSERT_EQ(skel->bss->tp_res, 0x20000 | 0x40000, "tp_res2"); cleanup: bpf_link__destroy(link1); bpf_link__destroy(link2); bpf_link__destroy(link3); } static void burn_cpu(void) { volatile int j = 0; cpu_set_t cpu_set; int i, err; /* generate some branches on cpu 0 */ CPU_ZERO(&cpu_set); CPU_SET(0, &cpu_set); err = pthread_setaffinity_np(pthread_self(), sizeof(cpu_set), &cpu_set); ASSERT_OK(err, "set_thread_affinity"); /* spin the loop for a while (random high number) */ for (i = 0; i < 1000000; ++i) ++j; } static void pe_subtest(struct test_bpf_cookie *skel) { DECLARE_LIBBPF_OPTS(bpf_perf_event_opts, opts); struct bpf_link *link = NULL; struct perf_event_attr attr; int pfd = -1; /* create perf event */ memset(&attr, 0, sizeof(attr)); attr.size = sizeof(attr); attr.type = PERF_TYPE_SOFTWARE; attr.config = PERF_COUNT_SW_CPU_CLOCK; attr.freq = 1; attr.sample_freq = 4000; pfd = syscall(__NR_perf_event_open, &attr, -1, 0, -1, PERF_FLAG_FD_CLOEXEC); if (!ASSERT_GE(pfd, 0, "perf_fd")) goto cleanup; opts.bpf_cookie = 0x100000; link = bpf_program__attach_perf_event_opts(skel->progs.handle_pe, pfd, &opts); if (!ASSERT_OK_PTR(link, "link1")) goto cleanup; burn_cpu(); /* trigger BPF prog */ ASSERT_EQ(skel->bss->pe_res, 0x100000, "pe_res1"); /* prevent bpf_link__destroy() closing pfd itself */ bpf_link__disconnect(link); /* close BPF link's FD explicitly */ close(bpf_link__fd(link)); /* free up memory used by struct bpf_link */ bpf_link__destroy(link); link = NULL; kern_sync_rcu(); skel->bss->pe_res = 0; opts.bpf_cookie = 0x200000; link = bpf_program__attach_perf_event_opts(skel->progs.handle_pe, pfd, &opts); if (!ASSERT_OK_PTR(link, "link2")) goto cleanup; burn_cpu(); /* trigger BPF prog */ ASSERT_EQ(skel->bss->pe_res, 0x200000, "pe_res2"); cleanup: close(pfd); bpf_link__destroy(link); } void test_bpf_cookie(void) { struct test_bpf_cookie *skel; skel = test_bpf_cookie__open_and_load(); if (!ASSERT_OK_PTR(skel, "skel_open")) return; skel->bss->my_tid = syscall(SYS_gettid); if (test__start_subtest("kprobe")) kprobe_subtest(skel); if (test__start_subtest("uprobe")) uprobe_subtest(skel); if (test__start_subtest("tracepoint")) tp_subtest(skel); if (test__start_subtest("perf_event")) pe_subtest(skel); test_bpf_cookie__destroy(skel); }