diff options
Diffstat (limited to 'tools/testing/selftests/bpf/test_current_pid_tgid_new_ns.c')
| -rw-r--r-- | tools/testing/selftests/bpf/test_current_pid_tgid_new_ns.c | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/test_current_pid_tgid_new_ns.c b/tools/testing/selftests/bpf/test_current_pid_tgid_new_ns.c new file mode 100644 index 000000000000..ed253f252cd0 --- /dev/null +++ b/tools/testing/selftests/bpf/test_current_pid_tgid_new_ns.c @@ -0,0 +1,159 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020 Carlos Neira cneirabustos@gmail.com */ +#define _GNU_SOURCE +#include <sys/stat.h> +#include <sys/types.h> +#include <unistd.h> +#include <sys/syscall.h> +#include <sched.h> +#include <sys/wait.h> +#include <sys/mount.h> +#include "test_progs.h" + +#define CHECK_NEWNS(condition, tag, format...) ({ \ + int __ret = !!(condition); \ + if (__ret) { \ + printf("%s:FAIL:%s ", __func__, tag); \ + printf(format); \ + } else { \ + printf("%s:PASS:%s\n", __func__, tag); \ + } \ + __ret; \ +}) + +struct bss { + __u64 dev; + __u64 ino; + __u64 pid_tgid; + __u64 user_pid_tgid; +}; + +int main(int argc, char **argv) +{ + pid_t pid; + int exit_code = 1; + struct stat st; + + printf("Testing bpf_get_ns_current_pid_tgid helper in new ns\n"); + + if (stat("/proc/self/ns/pid", &st)) { + perror("stat failed on /proc/self/ns/pid ns\n"); + printf("%s:FAILED\n", argv[0]); + return exit_code; + } + + if (CHECK_NEWNS(unshare(CLONE_NEWPID | CLONE_NEWNS), + "unshare CLONE_NEWPID | CLONE_NEWNS", "error errno=%d\n", errno)) + return exit_code; + + pid = fork(); + if (pid == -1) { + perror("Fork() failed\n"); + printf("%s:FAILED\n", argv[0]); + return exit_code; + } + + if (pid > 0) { + int status; + + usleep(5); + waitpid(pid, &status, 0); + return 0; + } else { + + pid = fork(); + if (pid == -1) { + perror("Fork() failed\n"); + printf("%s:FAILED\n", argv[0]); + return exit_code; + } + + if (pid > 0) { + int status; + waitpid(pid, &status, 0); + return 0; + } else { + if (CHECK_NEWNS(mount("none", "/proc", NULL, MS_PRIVATE|MS_REC, NULL), + "Unmounting proc", "Cannot umount proc! errno=%d\n", errno)) + return exit_code; + + if (CHECK_NEWNS(mount("proc", "/proc", "proc", MS_NOSUID|MS_NOEXEC|MS_NODEV, NULL), + "Mounting proc", "Cannot mount proc! errno=%d\n", errno)) + return exit_code; + + const char *probe_name = "raw_tracepoint/sys_enter"; + const char *file = "test_ns_current_pid_tgid.o"; + struct bpf_link *link = NULL; + struct bpf_program *prog; + struct bpf_map *bss_map; + struct bpf_object *obj; + int exit_code = 1; + int err, key = 0; + struct bss bss; + struct stat st; + __u64 id; + + obj = bpf_object__open_file(file, NULL); + if (CHECK_NEWNS(IS_ERR(obj), "obj_open", "err %ld\n", PTR_ERR(obj))) + return exit_code; + + err = bpf_object__load(obj); + if (CHECK_NEWNS(err, "obj_load", "err %d errno %d\n", err, errno)) + goto cleanup; + + bss_map = bpf_object__find_map_by_name(obj, "test_ns_.bss"); + if (CHECK_NEWNS(!bss_map, "find_bss_map", "failed\n")) + goto cleanup; + + prog = bpf_object__find_program_by_title(obj, probe_name); + if (CHECK_NEWNS(!prog, "find_prog", "prog '%s' not found\n", + probe_name)) + goto cleanup; + + memset(&bss, 0, sizeof(bss)); + pid_t tid = syscall(SYS_gettid); + pid_t pid = getpid(); + + id = (__u64) tid << 32 | pid; + bss.user_pid_tgid = id; + + if (CHECK_NEWNS(stat("/proc/self/ns/pid", &st), + "stat new ns", "Failed to stat /proc/self/ns/pid errno=%d\n", errno)) + goto cleanup; + + bss.dev = st.st_dev; + bss.ino = st.st_ino; + + err = bpf_map_update_elem(bpf_map__fd(bss_map), &key, &bss, 0); + if (CHECK_NEWNS(err, "setting_bss", "failed to set bss : %d\n", err)) + goto cleanup; + + link = bpf_program__attach_raw_tracepoint(prog, "sys_enter"); + if (CHECK_NEWNS(IS_ERR(link), "attach_raw_tp", "err %ld\n", + PTR_ERR(link))) { + link = NULL; + goto cleanup; + } + + /* trigger some syscalls */ + usleep(1); + + err = bpf_map_lookup_elem(bpf_map__fd(bss_map), &key, &bss); + if (CHECK_NEWNS(err, "set_bss", "failed to get bss : %d\n", err)) + goto cleanup; + + if (CHECK_NEWNS(id != bss.pid_tgid, "Compare user pid/tgid vs. bpf pid/tgid", + "User pid/tgid %llu BPF pid/tgid %llu\n", id, bss.pid_tgid)) + goto cleanup; + + exit_code = 0; + printf("%s:PASS\n", argv[0]); +cleanup: + if (!link) { + bpf_link__destroy(link); + link = NULL; + } + bpf_object__close(obj); + } + } +} |