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// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2021 Facebook */
#define _GNU_SOURCE
#include <pthread.h>
#include <sched.h>
#include <sys/syscall.h>
#include <unistd.h>
#include <test_progs.h>
#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);
}
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