311 lines
6.8 KiB
C
311 lines
6.8 KiB
C
|
// SPDX-License-Identifier: GPL-2.0
|
||
|
|
|
||
|
|
#define _GNU_SOURCE
|
||
|
|
#include <assert.h>
|
||
|
|
#include <errno.h>
|
||
|
|
#include <fcntl.h>
|
||
|
|
#include <linux/types.h>
|
||
|
|
#include <sched.h>
|
||
|
|
#include <signal.h>
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <string.h>
|
||
|
|
#include <syscall.h>
|
||
|
|
#include <sys/wait.h>
|
||
|
|
#include <sys/mman.h>
|
||
|
|
|
||
|
|
#include "pidfd.h"
|
||
|
|
#include "../kselftest.h"
|
||
|
|
|
||
|
|
struct error {
|
||
|
|
int code;
|
||
|
|
char msg[512];
|
||
|
|
};
|
||
|
|
|
||
|
|
static int error_set(struct error *err, int code, const char *fmt, ...)
|
||
|
|
{
|
||
|
|
va_list args;
|
||
|
|
int r;
|
||
|
|
|
||
|
|
if (code == PIDFD_PASS || !err || err->code != PIDFD_PASS)
|
||
|
|
return code;
|
||
|
|
|
||
|
|
err->code = code;
|
||
|
|
va_start(args, fmt);
|
||
|
|
r = vsnprintf(err->msg, sizeof(err->msg), fmt, args);
|
||
|
|
assert((size_t)r < sizeof(err->msg));
|
||
|
|
va_end(args);
|
||
|
|
|
||
|
|
return code;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void error_report(struct error *err, const char *test_name)
|
||
|
|
{
|
||
|
|
switch (err->code) {
|
||
|
|
case PIDFD_ERROR:
|
||
|
|
ksft_exit_fail_msg("%s test: Fatal: %s\n", test_name, err->msg);
|
||
|
|
break;
|
||
|
|
|
||
|
|
case PIDFD_FAIL:
|
||
|
|
/* will be: not ok %d # error %s test: %s */
|
||
|
|
ksft_test_result_error("%s test: %s\n", test_name, err->msg);
|
||
|
|
break;
|
||
|
|
|
||
|
|
case PIDFD_SKIP:
|
||
|
|
/* will be: not ok %d # SKIP %s test: %s */
|
||
|
|
ksft_test_result_skip("%s test: %s\n", test_name, err->msg);
|
||
|
|
break;
|
||
|
|
|
||
|
|
case PIDFD_XFAIL:
|
||
|
|
ksft_test_result_pass("%s test: Expected failure: %s\n",
|
||
|
|
test_name, err->msg);
|
||
|
|
break;
|
||
|
|
|
||
|
|
case PIDFD_PASS:
|
||
|
|
ksft_test_result_pass("%s test: Passed\n");
|
||
|
|
break;
|
||
|
|
|
||
|
|
default:
|
||
|
|
ksft_exit_fail_msg("%s test: Unknown code: %d %s\n",
|
||
|
|
test_name, err->code, err->msg);
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int error_check(struct error *err, const char *test_name)
|
||
|
|
{
|
||
|
|
/* In case of error we bail out and terminate the test program */
|
||
|
|
if (err->code == PIDFD_ERROR)
|
||
|
|
error_report(err, test_name);
|
||
|
|
|
||
|
|
return err->code;
|
||
|
|
}
|
||
|
|
|
||
|
|
#define CHILD_STACK_SIZE 8192
|
||
|
|
|
||
|
|
struct child {
|
||
|
|
char *stack;
|
||
|
|
pid_t pid;
|
||
|
|
int fd;
|
||
|
|
};
|
||
|
|
|
||
|
|
static struct child clone_newns(int (*fn)(void *), void *args,
|
||
|
|
struct error *err)
|
||
|
|
{
|
||
|
|
static int flags = CLONE_PIDFD | CLONE_NEWPID | CLONE_NEWNS | SIGCHLD;
|
||
|
|
struct child ret;
|
||
|
|
|
||
|
|
if (!(flags & CLONE_NEWUSER) && geteuid() != 0)
|
||
|
|
flags |= CLONE_NEWUSER;
|
||
|
|
|
||
|
|
ret.stack = mmap(NULL, CHILD_STACK_SIZE, PROT_READ | PROT_WRITE,
|
||
|
|
MAP_PRIVATE | MAP_ANONYMOUS | MAP_STACK, -1, 0);
|
||
|
|
if (ret.stack == MAP_FAILED) {
|
||
|
|
error_set(err, -1, "mmap of stack failed (errno %d)", errno);
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
#ifdef __ia64__
|
||
|
|
ret.pid = __clone2(fn, ret.stack, CHILD_STACK_SIZE, flags, args, &ret.fd);
|
||
|
|
#else
|
||
|
|
ret.pid = clone(fn, ret.stack + CHILD_STACK_SIZE, flags, args, &ret.fd);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
if (ret.pid < 0) {
|
||
|
|
error_set(err, PIDFD_ERROR, "clone failed (ret %d, errno %d)",
|
||
|
|
ret.fd, errno);
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
ksft_print_msg("New child: %d, fd: %d\n", ret.pid, ret.fd);
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline void child_close(struct child *child)
|
||
|
|
{
|
||
|
|
close(child->fd);
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int child_join(struct child *child, struct error *err)
|
||
|
|
{
|
||
|
|
int r;
|
||
|
|
|
||
|
|
r = wait_for_pid(child->pid);
|
||
|
|
if (r < 0)
|
||
|
|
error_set(err, PIDFD_ERROR, "waitpid failed (ret %d, errno %d)",
|
||
|
|
r, errno);
|
||
|
|
else if (r > 0)
|
||
|
|
error_set(err, r, "child %d reported: %d", child->pid, r);
|
||
|
|
|
||
|
|
if (munmap(child->stack, CHILD_STACK_SIZE)) {
|
||
|
|
error_set(err, -1, "munmap of child stack failed (errno %d)", errno);
|
||
|
|
r = -1;
|
||
|
|
}
|
||
|
|
|
||
|
|
return r;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int child_join_close(struct child *child, struct error *err)
|
||
|
|
{
|
||
|
|
child_close(child);
|
||
|
|
return child_join(child, err);
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline void trim_newline(char *str)
|
||
|
|
{
|
||
|
|
char *pos = strrchr(str, '\n');
|
||
|
|
|
||
|
|
if (pos)
|
||
|
|
*pos = '\0';
|
||
|
|
}
|
||
|
|
|
||
|
|
static int verify_fdinfo(int pidfd, struct error *err, const char *prefix,
|
||
|
|
size_t prefix_len, const char *expect, ...)
|
||
|
|
{
|
||
|
|
char buffer[512] = {0, };
|
||
|
|
char path[512] = {0, };
|
||
|
|
va_list args;
|
||
|
|
FILE *f;
|
||
|
|
char *line = NULL;
|
||
|
|
size_t n = 0;
|
||
|
|
int found = 0;
|
||
|
|
int r;
|
||
|
|
|
||
|
|
va_start(args, expect);
|
||
|
|
r = vsnprintf(buffer, sizeof(buffer), expect, args);
|
||
|
|
assert((size_t)r < sizeof(buffer));
|
||
|
|
va_end(args);
|
||
|
|
|
||
|
|
snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", pidfd);
|
||
|
|
f = fopen(path, "re");
|
||
|
|
if (!f)
|
||
|
|
return error_set(err, PIDFD_ERROR, "fdinfo open failed for %d",
|
||
|
|
pidfd);
|
||
|
|
|
||
|
|
while (getline(&line, &n, f) != -1) {
|
||
|
|
char *val;
|
||
|
|
|
||
|
|
if (strncmp(line, prefix, prefix_len))
|
||
|
|
continue;
|
||
|
|
|
||
|
|
found = 1;
|
||
|
|
|
||
|
|
val = line + prefix_len;
|
||
|
|
r = strcmp(val, buffer);
|
||
|
|
if (r != 0) {
|
||
|
|
trim_newline(line);
|
||
|
|
trim_newline(buffer);
|
||
|
|
error_set(err, PIDFD_FAIL, "%s '%s' != '%s'",
|
||
|
|
prefix, val, buffer);
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
|
||
|
|
free(line);
|
||
|
|
fclose(f);
|
||
|
|
|
||
|
|
if (found == 0)
|
||
|
|
return error_set(err, PIDFD_FAIL, "%s not found for fd %d",
|
||
|
|
prefix, pidfd);
|
||
|
|
|
||
|
|
return PIDFD_PASS;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int child_fdinfo_nspid_test(void *args)
|
||
|
|
{
|
||
|
|
struct error err;
|
||
|
|
int pidfd;
|
||
|
|
int r;
|
||
|
|
|
||
|
|
/* if we got no fd for the sibling, we are done */
|
||
|
|
if (!args)
|
||
|
|
return PIDFD_PASS;
|
||
|
|
|
||
|
|
/* verify that we can not resolve the pidfd for a process
|
||
|
|
* in a sibling pid namespace, i.e. a pid namespace it is
|
||
|
|
* not in our or a descended namespace
|
||
|
|
*/
|
||
|
|
r = mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, 0);
|
||
|
|
if (r < 0) {
|
||
|
|
ksft_print_msg("Failed to remount / private\n");
|
||
|
|
return PIDFD_ERROR;
|
||
|
|
}
|
||
|
|
|
||
|
|
(void)umount2("/proc", MNT_DETACH);
|
||
|
|
r = mount("proc", "/proc", "proc", 0, NULL);
|
||
|
|
if (r < 0) {
|
||
|
|
ksft_print_msg("Failed to remount /proc\n");
|
||
|
|
return PIDFD_ERROR;
|
||
|
|
}
|
||
|
|
|
||
|
|
pidfd = *(int *)args;
|
||
|
|
r = verify_fdinfo(pidfd, &err, "NSpid:", 6, "\t0\n");
|
||
|
|
|
||
|
|
if (r != PIDFD_PASS)
|
||
|
|
ksft_print_msg("NSpid fdinfo check failed: %s\n", err.msg);
|
||
|
|
|
||
|
|
return r;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void test_pidfd_fdinfo_nspid(void)
|
||
|
|
{
|
||
|
|
struct child a, b;
|
||
|
|
struct error err = {0, };
|
||
|
|
const char *test_name = "pidfd check for NSpid in fdinfo";
|
||
|
|
|
||
|
|
/* Create a new child in a new pid and mount namespace */
|
||
|
|
a = clone_newns(child_fdinfo_nspid_test, NULL, &err);
|
||
|
|
error_check(&err, test_name);
|
||
|
|
|
||
|
|
/* Pass the pidfd representing the first child to the
|
||
|
|
* second child, which will be in a sibling pid namespace,
|
||
|
|
* which means that the fdinfo NSpid entry for the pidfd
|
||
|
|
* should only contain '0'.
|
||
|
|
*/
|
||
|
|
b = clone_newns(child_fdinfo_nspid_test, &a.fd, &err);
|
||
|
|
error_check(&err, test_name);
|
||
|
|
|
||
|
|
/* The children will have pid 1 in the new pid namespace,
|
||
|
|
* so the line must be 'NSPid:\t<pid>\t1'.
|
||
|
|
*/
|
||
|
|
verify_fdinfo(a.fd, &err, "NSpid:", 6, "\t%d\t%d\n", a.pid, 1);
|
||
|
|
verify_fdinfo(b.fd, &err, "NSpid:", 6, "\t%d\t%d\n", b.pid, 1);
|
||
|
|
|
||
|
|
/* wait for the process, check the exit status and set
|
||
|
|
* 'err' accordingly, if it is not already set.
|
||
|
|
*/
|
||
|
|
child_join_close(&a, &err);
|
||
|
|
child_join_close(&b, &err);
|
||
|
|
|
||
|
|
error_report(&err, test_name);
|
||
|
|
}
|
||
|
|
|
||
|
|
static void test_pidfd_dead_fdinfo(void)
|
||
|
|
{
|
||
|
|
struct child a;
|
||
|
|
struct error err = {0, };
|
||
|
|
const char *test_name = "pidfd check fdinfo for dead process";
|
||
|
|
|
||
|
|
/* Create a new child in a new pid and mount namespace */
|
||
|
|
a = clone_newns(child_fdinfo_nspid_test, NULL, &err);
|
||
|
|
error_check(&err, test_name);
|
||
|
|
child_join(&a, &err);
|
||
|
|
|
||
|
|
verify_fdinfo(a.fd, &err, "Pid:", 4, "\t-1\n");
|
||
|
|
verify_fdinfo(a.fd, &err, "NSpid:", 6, "\t-1\n");
|
||
|
|
child_close(&a);
|
||
|
|
error_report(&err, test_name);
|
||
|
|
}
|
||
|
|
|
||
|
|
int main(int argc, char **argv)
|
||
|
|
{
|
||
|
|
ksft_print_header();
|
||
|
|
ksft_set_plan(2);
|
||
|
|
|
||
|
|
test_pidfd_fdinfo_nspid();
|
||
|
|
test_pidfd_dead_fdinfo();
|
||
|
|
|
||
|
|
return ksft_exit_pass();
|
||
|
|
}
|