tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2
3#ifndef __PIDFD_H
4#define __PIDFD_H
5
6#define _GNU_SOURCE
7#include <errno.h>
8#include <fcntl.h>
9#include <sched.h>
10#include <signal.h>
11#include <stdio.h>
12#include <stdlib.h>
13#include <string.h>
14#include <syscall.h>
15#include <sys/ioctl.h>
16#include <sys/types.h>
17#include <sys/wait.h>
18
19#include "../kselftest.h"
20#include "../clone3/clone3_selftests.h"
21
22#ifndef P_PIDFD
23#define P_PIDFD 3
24#endif
25
26#ifndef CLONE_NEWTIME
27#define CLONE_NEWTIME 0x00000080
28#endif
29
30#ifndef CLONE_PIDFD
31#define CLONE_PIDFD 0x00001000
32#endif
33
34#ifndef __NR_pidfd_open
35#define __NR_pidfd_open 434
36#endif
37
38#ifndef __NR_pidfd_send_signal
39#define __NR_pidfd_send_signal 424
40#endif
41
42#ifndef __NR_clone3
43#define __NR_clone3 435
44#endif
45
46#ifndef __NR_pidfd_getfd
47#define __NR_pidfd_getfd 438
48#endif
49
50#ifndef PIDFD_NONBLOCK
51#define PIDFD_NONBLOCK O_NONBLOCK
52#endif
53
54#ifndef PIDFD_SELF_THREAD
55#define PIDFD_SELF_THREAD -10000 /* Current thread. */
56#endif
57
58#ifndef PIDFD_SELF_THREAD_GROUP
59#define PIDFD_SELF_THREAD_GROUP -20000 /* Current thread group leader. */
60#endif
61
62#ifndef PIDFD_SELF
63#define PIDFD_SELF PIDFD_SELF_THREAD
64#endif
65
66#ifndef PIDFD_SELF_PROCESS
67#define PIDFD_SELF_PROCESS PIDFD_SELF_THREAD_GROUP
68#endif
69
70#ifndef PIDFS_IOCTL_MAGIC
71#define PIDFS_IOCTL_MAGIC 0xFF
72#endif
73
74#ifndef PIDFD_GET_CGROUP_NAMESPACE
75#define PIDFD_GET_CGROUP_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 1)
76#endif
77
78#ifndef PIDFD_GET_IPC_NAMESPACE
79#define PIDFD_GET_IPC_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 2)
80#endif
81
82#ifndef PIDFD_GET_MNT_NAMESPACE
83#define PIDFD_GET_MNT_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 3)
84#endif
85
86#ifndef PIDFD_GET_NET_NAMESPACE
87#define PIDFD_GET_NET_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 4)
88#endif
89
90#ifndef PIDFD_GET_PID_NAMESPACE
91#define PIDFD_GET_PID_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 5)
92#endif
93
94#ifndef PIDFD_GET_PID_FOR_CHILDREN_NAMESPACE
95#define PIDFD_GET_PID_FOR_CHILDREN_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 6)
96#endif
97
98#ifndef PIDFD_GET_TIME_NAMESPACE
99#define PIDFD_GET_TIME_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 7)
100#endif
101
102#ifndef PIDFD_GET_TIME_FOR_CHILDREN_NAMESPACE
103#define PIDFD_GET_TIME_FOR_CHILDREN_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 8)
104#endif
105
106#ifndef PIDFD_GET_USER_NAMESPACE
107#define PIDFD_GET_USER_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 9)
108#endif
109
110#ifndef PIDFD_GET_UTS_NAMESPACE
111#define PIDFD_GET_UTS_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 10)
112#endif
113
114#ifndef PIDFD_GET_INFO
115#define PIDFD_GET_INFO _IOWR(PIDFS_IOCTL_MAGIC, 11, struct pidfd_info)
116#endif
117
118#ifndef PIDFD_INFO_PID
119#define PIDFD_INFO_PID (1UL << 0) /* Always returned, even if not requested */
120#endif
121
122#ifndef PIDFD_INFO_CREDS
123#define PIDFD_INFO_CREDS (1UL << 1) /* Always returned, even if not requested */
124#endif
125
126#ifndef PIDFD_INFO_CGROUPID
127#define PIDFD_INFO_CGROUPID (1UL << 2) /* Always returned if available, even if not requested */
128#endif
129
130#ifndef PIDFD_INFO_EXIT
131#define PIDFD_INFO_EXIT (1UL << 3) /* Always returned if available, even if not requested */
132#endif
133
134#ifndef PIDFD_THREAD
135#define PIDFD_THREAD O_EXCL
136#endif
137
138struct pidfd_info {
139 __u64 mask;
140 __u64 cgroupid;
141 __u32 pid;
142 __u32 tgid;
143 __u32 ppid;
144 __u32 ruid;
145 __u32 rgid;
146 __u32 euid;
147 __u32 egid;
148 __u32 suid;
149 __u32 sgid;
150 __u32 fsuid;
151 __u32 fsgid;
152 __s32 exit_code;
153};
154
155/*
156 * The kernel reserves 300 pids via RESERVED_PIDS in kernel/pid.c
157 * That means, when it wraps around any pid < 300 will be skipped.
158 * So we need to use a pid > 300 in order to test recycling.
159 */
160#define PID_RECYCLE 1000
161
162/*
163 * Define a few custom error codes for the child process to clearly indicate
164 * what is happening. This way we can tell the difference between a system
165 * error, a test error, etc.
166 */
167#define PIDFD_PASS 0
168#define PIDFD_FAIL 1
169#define PIDFD_ERROR 2
170#define PIDFD_SKIP 3
171#define PIDFD_XFAIL 4
172
173static inline int sys_waitid(int which, pid_t pid, siginfo_t *info, int options)
174{
175 return syscall(__NR_waitid, which, pid, info, options, NULL);
176}
177
178static inline int wait_for_pid(pid_t pid)
179{
180 int status, ret;
181
182again:
183 ret = waitpid(pid, &status, 0);
184 if (ret == -1) {
185 if (errno == EINTR)
186 goto again;
187
188 ksft_print_msg("waitpid returned -1, errno=%d\n", errno);
189 return -1;
190 }
191
192 if (!WIFEXITED(status)) {
193 ksft_print_msg(
194 "waitpid !WIFEXITED, WIFSIGNALED=%d, WTERMSIG=%d\n",
195 WIFSIGNALED(status), WTERMSIG(status));
196 return -1;
197 }
198
199 ret = WEXITSTATUS(status);
200 return ret;
201}
202
203static inline int sys_pidfd_open(pid_t pid, unsigned int flags)
204{
205 return syscall(__NR_pidfd_open, pid, flags);
206}
207
208static inline int sys_pidfd_send_signal(int pidfd, int sig, siginfo_t *info,
209 unsigned int flags)
210{
211 return syscall(__NR_pidfd_send_signal, pidfd, sig, info, flags);
212}
213
214static inline int sys_pidfd_getfd(int pidfd, int fd, int flags)
215{
216 return syscall(__NR_pidfd_getfd, pidfd, fd, flags);
217}
218
219static inline int sys_memfd_create(const char *name, unsigned int flags)
220{
221 return syscall(__NR_memfd_create, name, flags);
222}
223
224static inline pid_t create_child(int *pidfd, unsigned flags)
225{
226 struct __clone_args args = {
227 .flags = CLONE_PIDFD | flags,
228 .exit_signal = SIGCHLD,
229 .pidfd = ptr_to_u64(pidfd),
230 };
231
232 return sys_clone3(&args, sizeof(struct __clone_args));
233}
234
235static inline ssize_t read_nointr(int fd, void *buf, size_t count)
236{
237 ssize_t ret;
238
239 do {
240 ret = read(fd, buf, count);
241 } while (ret < 0 && errno == EINTR);
242
243 return ret;
244}
245
246static inline ssize_t write_nointr(int fd, const void *buf, size_t count)
247{
248 ssize_t ret;
249
250 do {
251 ret = write(fd, buf, count);
252 } while (ret < 0 && errno == EINTR);
253
254 return ret;
255}
256
257static inline int sys_execveat(int dirfd, const char *pathname,
258 char *const argv[], char *const envp[],
259 int flags)
260{
261 return syscall(__NR_execveat, dirfd, pathname, argv, envp, flags);
262}
263
264#endif /* __PIDFD_H */