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 /*
20 * Remove the userspace definitions of the following preprocessor symbols
21 * to avoid duplicate-definition warnings from the subsequent in-kernel
22 * definitions.
23 */
24 #undef SCHED_NORMAL
25 #undef SCHED_FLAG_KEEP_ALL
26 #undef SCHED_FLAG_UTIL_CLAMP
27
28 #include "../kselftest.h"
29 #include "../clone3/clone3_selftests.h"
30
31 #ifndef FD_PIDFS_ROOT
32 #define FD_PIDFS_ROOT -10002
33 #endif
34
35 #ifndef P_PIDFD
36 #define P_PIDFD 3
37 #endif
38
39 #ifndef CLONE_NEWTIME
40 #define CLONE_NEWTIME 0x00000080
41 #endif
42
43 #ifndef CLONE_PIDFD
44 #define CLONE_PIDFD 0x00001000
45 #endif
46
47 #ifndef __NR_pidfd_open
48 #define __NR_pidfd_open 434
49 #endif
50
51 #ifndef __NR_pidfd_send_signal
52 #define __NR_pidfd_send_signal 424
53 #endif
54
55 #ifndef __NR_clone3
56 #define __NR_clone3 435
57 #endif
58
59 #ifndef __NR_pidfd_getfd
60 #define __NR_pidfd_getfd 438
61 #endif
62
63 #ifndef PIDFD_NONBLOCK
64 #define PIDFD_NONBLOCK O_NONBLOCK
65 #endif
66
67 #ifndef PIDFD_SELF_THREAD
68 #define PIDFD_SELF_THREAD -10000 /* Current thread. */
69 #endif
70
71 #ifndef PIDFD_SELF_THREAD_GROUP
72 #define PIDFD_SELF_THREAD_GROUP -10001 /* Current thread group leader. */
73 #endif
74
75 #ifndef PIDFD_SELF
76 #define PIDFD_SELF PIDFD_SELF_THREAD
77 #endif
78
79 #ifndef PIDFD_SELF_PROCESS
80 #define PIDFD_SELF_PROCESS PIDFD_SELF_THREAD_GROUP
81 #endif
82
83 #ifndef PIDFS_IOCTL_MAGIC
84 #define PIDFS_IOCTL_MAGIC 0xFF
85 #endif
86
87 #ifndef PIDFD_GET_CGROUP_NAMESPACE
88 #define PIDFD_GET_CGROUP_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 1)
89 #endif
90
91 #ifndef PIDFD_GET_IPC_NAMESPACE
92 #define PIDFD_GET_IPC_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 2)
93 #endif
94
95 #ifndef PIDFD_GET_MNT_NAMESPACE
96 #define PIDFD_GET_MNT_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 3)
97 #endif
98
99 #ifndef PIDFD_GET_NET_NAMESPACE
100 #define PIDFD_GET_NET_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 4)
101 #endif
102
103 #ifndef PIDFD_GET_PID_NAMESPACE
104 #define PIDFD_GET_PID_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 5)
105 #endif
106
107 #ifndef PIDFD_GET_PID_FOR_CHILDREN_NAMESPACE
108 #define PIDFD_GET_PID_FOR_CHILDREN_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 6)
109 #endif
110
111 #ifndef PIDFD_GET_TIME_NAMESPACE
112 #define PIDFD_GET_TIME_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 7)
113 #endif
114
115 #ifndef PIDFD_GET_TIME_FOR_CHILDREN_NAMESPACE
116 #define PIDFD_GET_TIME_FOR_CHILDREN_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 8)
117 #endif
118
119 #ifndef PIDFD_GET_USER_NAMESPACE
120 #define PIDFD_GET_USER_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 9)
121 #endif
122
123 #ifndef PIDFD_GET_UTS_NAMESPACE
124 #define PIDFD_GET_UTS_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 10)
125 #endif
126
127 #ifndef PIDFD_GET_INFO
128 #define PIDFD_GET_INFO _IOWR(PIDFS_IOCTL_MAGIC, 11, struct pidfd_info)
129 #endif
130
131 #ifndef PIDFD_INFO_PID
132 #define PIDFD_INFO_PID (1UL << 0) /* Always returned, even if not requested */
133 #endif
134
135 #ifndef PIDFD_INFO_CREDS
136 #define PIDFD_INFO_CREDS (1UL << 1) /* Always returned, even if not requested */
137 #endif
138
139 #ifndef PIDFD_INFO_CGROUPID
140 #define PIDFD_INFO_CGROUPID (1UL << 2) /* Always returned if available, even if not requested */
141 #endif
142
143 #ifndef PIDFD_INFO_EXIT
144 #define PIDFD_INFO_EXIT (1UL << 3) /* Always returned if available, even if not requested */
145 #endif
146
147 #ifndef PIDFD_INFO_COREDUMP
148 #define PIDFD_INFO_COREDUMP (1UL << 4)
149 #endif
150
151 #ifndef PIDFD_COREDUMPED
152 #define PIDFD_COREDUMPED (1U << 0) /* Did crash and... */
153 #endif
154
155 #ifndef PIDFD_COREDUMP_SKIP
156 #define PIDFD_COREDUMP_SKIP (1U << 1) /* coredumping generation was skipped. */
157 #endif
158
159 #ifndef PIDFD_COREDUMP_USER
160 #define PIDFD_COREDUMP_USER (1U << 2) /* coredump was done as the user. */
161 #endif
162
163 #ifndef PIDFD_COREDUMP_ROOT
164 #define PIDFD_COREDUMP_ROOT (1U << 3) /* coredump was done as root. */
165 #endif
166
167 #ifndef PIDFD_THREAD
168 #define PIDFD_THREAD O_EXCL
169 #endif
170
171 struct pidfd_info {
172 __u64 mask;
173 __u64 cgroupid;
174 __u32 pid;
175 __u32 tgid;
176 __u32 ppid;
177 __u32 ruid;
178 __u32 rgid;
179 __u32 euid;
180 __u32 egid;
181 __u32 suid;
182 __u32 sgid;
183 __u32 fsuid;
184 __u32 fsgid;
185 __s32 exit_code;
186 __u32 coredump_mask;
187 __u32 __spare1;
188 };
189
190 /*
191 * The kernel reserves 300 pids via RESERVED_PIDS in kernel/pid.c
192 * That means, when it wraps around any pid < 300 will be skipped.
193 * So we need to use a pid > 300 in order to test recycling.
194 */
195 #define PID_RECYCLE 1000
196
197 /*
198 * Define a few custom error codes for the child process to clearly indicate
199 * what is happening. This way we can tell the difference between a system
200 * error, a test error, etc.
201 */
202 #define PIDFD_PASS 0
203 #define PIDFD_FAIL 1
204 #define PIDFD_ERROR 2
205 #define PIDFD_SKIP 3
206 #define PIDFD_XFAIL 4
207
sys_waitid(int which,pid_t pid,siginfo_t * info,int options)208 static inline int sys_waitid(int which, pid_t pid, siginfo_t *info, int options)
209 {
210 return syscall(__NR_waitid, which, pid, info, options, NULL);
211 }
212
wait_for_pid(pid_t pid)213 static inline int wait_for_pid(pid_t pid)
214 {
215 int status, ret;
216
217 again:
218 ret = waitpid(pid, &status, 0);
219 if (ret == -1) {
220 if (errno == EINTR)
221 goto again;
222
223 ksft_print_msg("waitpid returned -1, errno=%d\n", errno);
224 return -1;
225 }
226
227 if (!WIFEXITED(status)) {
228 ksft_print_msg(
229 "waitpid !WIFEXITED, WIFSIGNALED=%d, WTERMSIG=%d\n",
230 WIFSIGNALED(status), WTERMSIG(status));
231 return -1;
232 }
233
234 ret = WEXITSTATUS(status);
235 return ret;
236 }
237
sys_pidfd_open(pid_t pid,unsigned int flags)238 static inline int sys_pidfd_open(pid_t pid, unsigned int flags)
239 {
240 return syscall(__NR_pidfd_open, pid, flags);
241 }
242
sys_pidfd_send_signal(int pidfd,int sig,siginfo_t * info,unsigned int flags)243 static inline int sys_pidfd_send_signal(int pidfd, int sig, siginfo_t *info,
244 unsigned int flags)
245 {
246 return syscall(__NR_pidfd_send_signal, pidfd, sig, info, flags);
247 }
248
sys_pidfd_getfd(int pidfd,int fd,int flags)249 static inline int sys_pidfd_getfd(int pidfd, int fd, int flags)
250 {
251 return syscall(__NR_pidfd_getfd, pidfd, fd, flags);
252 }
253
sys_memfd_create(const char * name,unsigned int flags)254 static inline int sys_memfd_create(const char *name, unsigned int flags)
255 {
256 return syscall(__NR_memfd_create, name, flags);
257 }
258
create_child(int * pidfd,unsigned flags)259 static inline pid_t create_child(int *pidfd, unsigned flags)
260 {
261 struct __clone_args args = {
262 .flags = CLONE_PIDFD | flags,
263 .exit_signal = SIGCHLD,
264 .pidfd = ptr_to_u64(pidfd),
265 };
266
267 return sys_clone3(&args, sizeof(struct __clone_args));
268 }
269
read_nointr(int fd,void * buf,size_t count)270 static inline ssize_t read_nointr(int fd, void *buf, size_t count)
271 {
272 ssize_t ret;
273
274 do {
275 ret = read(fd, buf, count);
276 } while (ret < 0 && errno == EINTR);
277
278 return ret;
279 }
280
write_nointr(int fd,const void * buf,size_t count)281 static inline ssize_t write_nointr(int fd, const void *buf, size_t count)
282 {
283 ssize_t ret;
284
285 do {
286 ret = write(fd, buf, count);
287 } while (ret < 0 && errno == EINTR);
288
289 return ret;
290 }
291
sys_execveat(int dirfd,const char * pathname,char * const argv[],char * const envp[],int flags)292 static inline int sys_execveat(int dirfd, const char *pathname,
293 char *const argv[], char *const envp[],
294 int flags)
295 {
296 return syscall(__NR_execveat, dirfd, pathname, argv, envp, flags);
297 }
298
299 #endif /* __PIDFD_H */
300