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// 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);
}
}
return 0;
}
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