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// SPDX-License-Identifier: GPL-2.0
#define _GNU_SOURCE
#include <pthread.h>
#include <sched.h>
#include <sys/socket.h>
#include <test_progs.h>
#define MAX_CNT_RAWTP 10ull
#define MAX_STACK_RAWTP 100
static int duration = 0;
struct get_stack_trace_t {
int pid;
int kern_stack_size;
int user_stack_size;
int user_stack_buildid_size;
__u64 kern_stack[MAX_STACK_RAWTP];
__u64 user_stack[MAX_STACK_RAWTP];
struct bpf_stack_build_id user_stack_buildid[MAX_STACK_RAWTP];
};
static void get_stack_print_output(void *ctx, int cpu, void *data, __u32 size)
{
bool good_kern_stack = false, good_user_stack = false;
const char *nonjit_func = "___bpf_prog_run";
/* perfbuf-submitted data is 4-byte aligned, but we need 8-byte
* alignment, so copy data into a local variable, for simplicity
*/
struct get_stack_trace_t e;
int i, num_stack;
struct ksym *ks;
memset(&e, 0, sizeof(e));
memcpy(&e, data, size <= sizeof(e) ? size : sizeof(e));
if (size < sizeof(struct get_stack_trace_t)) {
__u64 *raw_data = data;
bool found = false;
num_stack = size / sizeof(__u64);
/* If jit is enabled, we do not have a good way to
* verify the sanity of the kernel stack. So we
* just assume it is good if the stack is not empty.
* This could be improved in the future.
*/
if (env.jit_enabled) {
found = num_stack > 0;
} else {
for (i = 0; i < num_stack; i++) {
ks = ksym_search(raw_data[i]);
if (ks && (strcmp(ks->name, nonjit_func) == 0)) {
found = true;
break;
}
}
}
if (found) {
good_kern_stack = true;
good_user_stack = true;
}
} else {
num_stack = e.kern_stack_size / sizeof(__u64);
if (env.jit_enabled) {
good_kern_stack = num_stack > 0;
} else {
for (i = 0; i < num_stack; i++) {
ks = ksym_search(e.kern_stack[i]);
if (ks && (strcmp(ks->name, nonjit_func) == 0)) {
good_kern_stack = true;
break;
}
}
}
if (e.user_stack_size > 0 && e.user_stack_buildid_size > 0)
good_user_stack = true;
}
if (!good_kern_stack)
CHECK(!good_kern_stack, "kern_stack", "corrupted kernel stack\n");
if (!good_user_stack)
CHECK(!good_user_stack, "user_stack", "corrupted user stack\n");
}
void test_get_stack_raw_tp(void)
{
const char *file = "./test_get_stack_rawtp.bpf.o";
const char *file_err = "./test_get_stack_rawtp_err.bpf.o";
const char *prog_name = "bpf_prog1";
int i, err, prog_fd, exp_cnt = MAX_CNT_RAWTP;
struct perf_buffer *pb = NULL;
struct bpf_link *link = NULL;
struct timespec tv = {0, 10};
struct bpf_program *prog;
struct bpf_object *obj;
struct bpf_map *map;
cpu_set_t cpu_set;
err = bpf_prog_test_load(file_err, BPF_PROG_TYPE_RAW_TRACEPOINT, &obj, &prog_fd);
if (CHECK(err >= 0, "prog_load raw tp", "err %d errno %d\n", err, errno))
return;
err = bpf_prog_test_load(file, BPF_PROG_TYPE_RAW_TRACEPOINT, &obj, &prog_fd);
if (CHECK(err, "prog_load raw tp", "err %d errno %d\n", err, errno))
return;
prog = bpf_object__find_program_by_name(obj, prog_name);
if (CHECK(!prog, "find_probe", "prog '%s' not found\n", prog_name))
goto close_prog;
map = bpf_object__find_map_by_name(obj, "perfmap");
if (CHECK(!map, "bpf_find_map", "not found\n"))
goto close_prog;
err = load_kallsyms();
if (CHECK(err < 0, "load_kallsyms", "err %d errno %d\n", err, errno))
goto close_prog;
CPU_ZERO(&cpu_set);
CPU_SET(0, &cpu_set);
err = pthread_setaffinity_np(pthread_self(), sizeof(cpu_set), &cpu_set);
if (CHECK(err, "set_affinity", "err %d, errno %d\n", err, errno))
goto close_prog;
link = bpf_program__attach_raw_tracepoint(prog, "sys_enter");
if (!ASSERT_OK_PTR(link, "attach_raw_tp"))
goto close_prog;
pb = perf_buffer__new(bpf_map__fd(map), 8, get_stack_print_output,
NULL, NULL, NULL);
if (!ASSERT_OK_PTR(pb, "perf_buf__new"))
goto close_prog;
/* trigger some syscall action */
for (i = 0; i < MAX_CNT_RAWTP; i++)
nanosleep(&tv, NULL);
while (exp_cnt > 0) {
err = perf_buffer__poll(pb, 100);
if (err < 0 && CHECK(err < 0, "pb__poll", "err %d\n", err))
goto close_prog;
exp_cnt -= err;
}
close_prog:
bpf_link__destroy(link);
perf_buffer__free(pb);
bpf_object__close(obj);
}
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