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
138 struct 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
sys_waitid(int which,pid_t pid,siginfo_t * info,int options)173 static 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
wait_for_pid(pid_t pid)178 static inline int wait_for_pid(pid_t pid)
179 {
180 int status, ret;
181
182 again:
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
sys_pidfd_open(pid_t pid,unsigned int flags)203 static inline int sys_pidfd_open(pid_t pid, unsigned int flags)
204 {
205 return syscall(__NR_pidfd_open, pid, flags);
206 }
207
sys_pidfd_send_signal(int pidfd,int sig,siginfo_t * info,unsigned int flags)208 static 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
sys_pidfd_getfd(int pidfd,int fd,int flags)214 static inline int sys_pidfd_getfd(int pidfd, int fd, int flags)
215 {
216 return syscall(__NR_pidfd_getfd, pidfd, fd, flags);
217 }
218
sys_memfd_create(const char * name,unsigned int flags)219 static inline int sys_memfd_create(const char *name, unsigned int flags)
220 {
221 return syscall(__NR_memfd_create, name, flags);
222 }
223
create_child(int * pidfd,unsigned flags)224 static 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
read_nointr(int fd,void * buf,size_t count)235 static 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
write_nointr(int fd,const void * buf,size_t count)246 static 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
sys_execveat(int dirfd,const char * pathname,char * const argv[],char * const envp[],int flags)257 static 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 */
265