diff options
Diffstat (limited to 'tools/testing/selftests/bpf/prog_tests/attach_probe.c')
-rw-r--r-- | tools/testing/selftests/bpf/prog_tests/attach_probe.c | 228 |
1 files changed, 228 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/attach_probe.c b/tools/testing/selftests/bpf/prog_tests/attach_probe.c new file mode 100644 index 000000000..9566d9d2f --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/attach_probe.c @@ -0,0 +1,228 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <test_progs.h> +#include "test_attach_probe.skel.h" + +/* this is how USDT semaphore is actually defined, except volatile modifier */ +volatile unsigned short uprobe_ref_ctr __attribute__((unused)) __attribute((section(".probes"))); + +/* uprobe attach point */ +static noinline void trigger_func(void) +{ + asm volatile (""); +} + +/* attach point for byname uprobe */ +static noinline void trigger_func2(void) +{ + asm volatile (""); +} + +/* attach point for byname sleepable uprobe */ +static noinline void trigger_func3(void) +{ + asm volatile (""); +} + +static char test_data[] = "test_data"; + +void test_attach_probe(void) +{ + DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, uprobe_opts); + struct bpf_link *kprobe_link, *kretprobe_link; + struct bpf_link *uprobe_link, *uretprobe_link; + struct test_attach_probe* skel; + ssize_t uprobe_offset, ref_ctr_offset; + struct bpf_link *uprobe_err_link; + bool legacy; + char *mem; + + /* Check if new-style kprobe/uprobe API is supported. + * Kernels that support new FD-based kprobe and uprobe BPF attachment + * through perf_event_open() syscall expose + * /sys/bus/event_source/devices/kprobe/type and + * /sys/bus/event_source/devices/uprobe/type files, respectively. They + * contain magic numbers that are passed as "type" field of + * perf_event_attr. Lack of such file in the system indicates legacy + * kernel with old-style kprobe/uprobe attach interface through + * creating per-probe event through tracefs. For such cases + * ref_ctr_offset feature is not supported, so we don't test it. + */ + legacy = access("/sys/bus/event_source/devices/kprobe/type", F_OK) != 0; + + uprobe_offset = get_uprobe_offset(&trigger_func); + if (!ASSERT_GE(uprobe_offset, 0, "uprobe_offset")) + return; + + ref_ctr_offset = get_rel_offset((uintptr_t)&uprobe_ref_ctr); + if (!ASSERT_GE(ref_ctr_offset, 0, "ref_ctr_offset")) + return; + + skel = test_attach_probe__open(); + if (!ASSERT_OK_PTR(skel, "skel_open")) + return; + + /* sleepable kprobe test case needs flags set before loading */ + if (!ASSERT_OK(bpf_program__set_flags(skel->progs.handle_kprobe_sleepable, + BPF_F_SLEEPABLE), "kprobe_sleepable_flags")) + goto cleanup; + + if (!ASSERT_OK(test_attach_probe__load(skel), "skel_load")) + goto cleanup; + if (!ASSERT_OK_PTR(skel->bss, "check_bss")) + goto cleanup; + + /* manual-attach kprobe/kretprobe */ + kprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kprobe, + false /* retprobe */, + SYS_NANOSLEEP_KPROBE_NAME); + if (!ASSERT_OK_PTR(kprobe_link, "attach_kprobe")) + goto cleanup; + skel->links.handle_kprobe = kprobe_link; + + kretprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kretprobe, + true /* retprobe */, + SYS_NANOSLEEP_KPROBE_NAME); + if (!ASSERT_OK_PTR(kretprobe_link, "attach_kretprobe")) + goto cleanup; + skel->links.handle_kretprobe = kretprobe_link; + + /* auto-attachable kprobe and kretprobe */ + skel->links.handle_kprobe_auto = bpf_program__attach(skel->progs.handle_kprobe_auto); + ASSERT_OK_PTR(skel->links.handle_kprobe_auto, "attach_kprobe_auto"); + + skel->links.handle_kretprobe_auto = bpf_program__attach(skel->progs.handle_kretprobe_auto); + ASSERT_OK_PTR(skel->links.handle_kretprobe_auto, "attach_kretprobe_auto"); + + if (!legacy) + ASSERT_EQ(uprobe_ref_ctr, 0, "uprobe_ref_ctr_before"); + + uprobe_opts.retprobe = false; + uprobe_opts.ref_ctr_offset = legacy ? 0 : ref_ctr_offset; + uprobe_link = bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe, + 0 /* self pid */, + "/proc/self/exe", + uprobe_offset, + &uprobe_opts); + if (!ASSERT_OK_PTR(uprobe_link, "attach_uprobe")) + goto cleanup; + skel->links.handle_uprobe = uprobe_link; + + if (!legacy) + ASSERT_GT(uprobe_ref_ctr, 0, "uprobe_ref_ctr_after"); + + /* if uprobe uses ref_ctr, uretprobe has to use ref_ctr as well */ + uprobe_opts.retprobe = true; + uprobe_opts.ref_ctr_offset = legacy ? 0 : ref_ctr_offset; + uretprobe_link = bpf_program__attach_uprobe_opts(skel->progs.handle_uretprobe, + -1 /* any pid */, + "/proc/self/exe", + uprobe_offset, &uprobe_opts); + if (!ASSERT_OK_PTR(uretprobe_link, "attach_uretprobe")) + goto cleanup; + skel->links.handle_uretprobe = uretprobe_link; + + /* verify auto-attach fails for old-style uprobe definition */ + uprobe_err_link = bpf_program__attach(skel->progs.handle_uprobe_byname); + if (!ASSERT_EQ(libbpf_get_error(uprobe_err_link), -EOPNOTSUPP, + "auto-attach should fail for old-style name")) + goto cleanup; + + uprobe_opts.func_name = "trigger_func2"; + uprobe_opts.retprobe = false; + uprobe_opts.ref_ctr_offset = 0; + skel->links.handle_uprobe_byname = + bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe_byname, + 0 /* this pid */, + "/proc/self/exe", + 0, &uprobe_opts); + if (!ASSERT_OK_PTR(skel->links.handle_uprobe_byname, "attach_uprobe_byname")) + goto cleanup; + + /* verify auto-attach works */ + skel->links.handle_uretprobe_byname = + bpf_program__attach(skel->progs.handle_uretprobe_byname); + if (!ASSERT_OK_PTR(skel->links.handle_uretprobe_byname, "attach_uretprobe_byname")) + goto cleanup; + + /* test attach by name for a library function, using the library + * as the binary argument. libc.so.6 will be resolved via dlopen()/dlinfo(). + */ + uprobe_opts.func_name = "malloc"; + uprobe_opts.retprobe = false; + skel->links.handle_uprobe_byname2 = + bpf_program__attach_uprobe_opts(skel->progs.handle_uprobe_byname2, + 0 /* this pid */, + "libc.so.6", + 0, &uprobe_opts); + if (!ASSERT_OK_PTR(skel->links.handle_uprobe_byname2, "attach_uprobe_byname2")) + goto cleanup; + + uprobe_opts.func_name = "free"; + uprobe_opts.retprobe = true; + skel->links.handle_uretprobe_byname2 = + bpf_program__attach_uprobe_opts(skel->progs.handle_uretprobe_byname2, + -1 /* any pid */, + "libc.so.6", + 0, &uprobe_opts); + if (!ASSERT_OK_PTR(skel->links.handle_uretprobe_byname2, "attach_uretprobe_byname2")) + goto cleanup; + + /* sleepable kprobes should not attach successfully */ + skel->links.handle_kprobe_sleepable = bpf_program__attach(skel->progs.handle_kprobe_sleepable); + if (!ASSERT_ERR_PTR(skel->links.handle_kprobe_sleepable, "attach_kprobe_sleepable")) + goto cleanup; + + /* test sleepable uprobe and uretprobe variants */ + skel->links.handle_uprobe_byname3_sleepable = bpf_program__attach(skel->progs.handle_uprobe_byname3_sleepable); + if (!ASSERT_OK_PTR(skel->links.handle_uprobe_byname3_sleepable, "attach_uprobe_byname3_sleepable")) + goto cleanup; + + skel->links.handle_uprobe_byname3 = bpf_program__attach(skel->progs.handle_uprobe_byname3); + if (!ASSERT_OK_PTR(skel->links.handle_uprobe_byname3, "attach_uprobe_byname3")) + goto cleanup; + + skel->links.handle_uretprobe_byname3_sleepable = bpf_program__attach(skel->progs.handle_uretprobe_byname3_sleepable); + if (!ASSERT_OK_PTR(skel->links.handle_uretprobe_byname3_sleepable, "attach_uretprobe_byname3_sleepable")) + goto cleanup; + + skel->links.handle_uretprobe_byname3 = bpf_program__attach(skel->progs.handle_uretprobe_byname3); + if (!ASSERT_OK_PTR(skel->links.handle_uretprobe_byname3, "attach_uretprobe_byname3")) + goto cleanup; + + skel->bss->user_ptr = test_data; + + /* trigger & validate kprobe && kretprobe */ + usleep(1); + + /* trigger & validate shared library u[ret]probes attached by name */ + mem = malloc(1); + free(mem); + + /* trigger & validate uprobe & uretprobe */ + trigger_func(); + + /* trigger & validate uprobe attached by name */ + trigger_func2(); + + /* trigger & validate sleepable uprobe attached by name */ + trigger_func3(); + + ASSERT_EQ(skel->bss->kprobe_res, 1, "check_kprobe_res"); + ASSERT_EQ(skel->bss->kprobe2_res, 11, "check_kprobe_auto_res"); + ASSERT_EQ(skel->bss->kretprobe_res, 2, "check_kretprobe_res"); + ASSERT_EQ(skel->bss->kretprobe2_res, 22, "check_kretprobe_auto_res"); + ASSERT_EQ(skel->bss->uprobe_res, 3, "check_uprobe_res"); + ASSERT_EQ(skel->bss->uretprobe_res, 4, "check_uretprobe_res"); + ASSERT_EQ(skel->bss->uprobe_byname_res, 5, "check_uprobe_byname_res"); + ASSERT_EQ(skel->bss->uretprobe_byname_res, 6, "check_uretprobe_byname_res"); + ASSERT_EQ(skel->bss->uprobe_byname2_res, 7, "check_uprobe_byname2_res"); + ASSERT_EQ(skel->bss->uretprobe_byname2_res, 8, "check_uretprobe_byname2_res"); + ASSERT_EQ(skel->bss->uprobe_byname3_sleepable_res, 9, "check_uprobe_byname3_sleepable_res"); + ASSERT_EQ(skel->bss->uprobe_byname3_res, 10, "check_uprobe_byname3_res"); + ASSERT_EQ(skel->bss->uretprobe_byname3_sleepable_res, 11, "check_uretprobe_byname3_sleepable_res"); + ASSERT_EQ(skel->bss->uretprobe_byname3_res, 12, "check_uretprobe_byname3_res"); + +cleanup: + test_attach_probe__destroy(skel); + ASSERT_EQ(uprobe_ref_ctr, 0, "uprobe_ref_ctr_cleanup"); +} |