1// SPDX-License-Identifier: GPL-2.0
2#define _GNU_SOURCE
3
4#include <stdio.h>
5#include <stdlib.h>
6#include <signal.h>
7#include <limits.h>
8#include <unistd.h>
9#include <errno.h>
10#include <string.h>
11#include <fcntl.h>
12#include <linux/unistd.h>
13#include <linux/kcmp.h>
14
15#include <sys/syscall.h>
16#include <sys/types.h>
17#include <sys/stat.h>
18#include <sys/wait.h>
19#include <sys/epoll.h>
20
21#include "../kselftest.h"
22
23static long sys_kcmp(int pid1, int pid2, int type, unsigned long fd1, unsigned long fd2)
24{
25	return syscall(__NR_kcmp, pid1, pid2, type, fd1, fd2);
26}
27
28static const unsigned int duped_num = 64;
29
30int main(int argc, char **argv)
31{
32	const char kpath[] = "kcmp-test-file";
33	struct kcmp_epoll_slot epoll_slot;
34	struct epoll_event ev;
35	int pid1, pid2;
36	int pipefd[2];
37	int fd1, fd2;
38	int epollfd;
39	int status;
40	int fddup;
41
42	fd1 = open(kpath, O_RDWR | O_CREAT | O_TRUNC, 0644);
43	pid1 = getpid();
44
45	if (fd1 < 0) {
46		perror("Can't create file");
47		ksft_exit_fail();
48	}
49
50	if (pipe(pipefd)) {
51		perror("Can't create pipe");
52		ksft_exit_fail();
53	}
54
55	epollfd = epoll_create1(0);
56	if (epollfd < 0) {
57		perror("epoll_create1 failed");
58		ksft_exit_fail();
59	}
60
61	memset(&ev, 0xff, sizeof(ev));
62	ev.events = EPOLLIN | EPOLLOUT;
63
64	if (epoll_ctl(epollfd, EPOLL_CTL_ADD, pipefd[0], &ev)) {
65		perror("epoll_ctl failed");
66		ksft_exit_fail();
67	}
68
69	fddup = dup2(pipefd[1], duped_num);
70	if (fddup < 0) {
71		perror("dup2 failed");
72		ksft_exit_fail();
73	}
74
75	if (epoll_ctl(epollfd, EPOLL_CTL_ADD, fddup, &ev)) {
76		perror("epoll_ctl failed");
77		ksft_exit_fail();
78	}
79	close(fddup);
80
81	pid2 = fork();
82	if (pid2 < 0) {
83		perror("fork failed");
84		ksft_exit_fail();
85	}
86
87	if (!pid2) {
88		int pid2 = getpid();
89		int ret;
90
91		fd2 = open(kpath, O_RDWR, 0644);
92		if (fd2 < 0) {
93			perror("Can't open file");
94			ksft_exit_fail();
95		}
96
97		/* An example of output and arguments */
98		printf("pid1: %6d pid2: %6d FD: %2ld FILES: %2ld VM: %2ld "
99		       "FS: %2ld SIGHAND: %2ld IO: %2ld SYSVSEM: %2ld "
100		       "INV: %2ld\n",
101		       pid1, pid2,
102		       sys_kcmp(pid1, pid2, KCMP_FILE,		fd1, fd2),
103		       sys_kcmp(pid1, pid2, KCMP_FILES,		0, 0),
104		       sys_kcmp(pid1, pid2, KCMP_VM,		0, 0),
105		       sys_kcmp(pid1, pid2, KCMP_FS,		0, 0),
106		       sys_kcmp(pid1, pid2, KCMP_SIGHAND,	0, 0),
107		       sys_kcmp(pid1, pid2, KCMP_IO,		0, 0),
108		       sys_kcmp(pid1, pid2, KCMP_SYSVSEM,	0, 0),
109
110			/* This one should fail */
111		       sys_kcmp(pid1, pid2, KCMP_TYPES + 1,	0, 0));
112
113		/* This one should return same fd */
114		ret = sys_kcmp(pid1, pid2, KCMP_FILE, fd1, fd1);
115		if (ret) {
116			printf("FAIL: 0 expected but %d returned (%s)\n",
117				ret, strerror(errno));
118			ksft_inc_fail_cnt();
119			ret = -1;
120		} else {
121			printf("PASS: 0 returned as expected\n");
122			ksft_inc_pass_cnt();
123		}
124
125		/* Compare with self */
126		ret = sys_kcmp(pid1, pid1, KCMP_VM, 0, 0);
127		if (ret) {
128			printf("FAIL: 0 expected but %d returned (%s)\n",
129				ret, strerror(errno));
130			ksft_inc_fail_cnt();
131			ret = -1;
132		} else {
133			printf("PASS: 0 returned as expected\n");
134			ksft_inc_pass_cnt();
135		}
136
137		/* Compare epoll target */
138		epoll_slot = (struct kcmp_epoll_slot) {
139			.efd	= epollfd,
140			.tfd	= duped_num,
141			.toff	= 0,
142		};
143		ret = sys_kcmp(pid1, pid1, KCMP_EPOLL_TFD, pipefd[1],
144			       (unsigned long)(void *)&epoll_slot);
145		if (ret) {
146			printf("FAIL: 0 expected but %d returned (%s)\n",
147				ret, strerror(errno));
148			ksft_inc_fail_cnt();
149			ret = -1;
150		} else {
151			printf("PASS: 0 returned as expected\n");
152			ksft_inc_pass_cnt();
153		}
154
155		ksft_print_cnts();
156
157		if (ret)
158			ksft_exit_fail();
159		else
160			ksft_exit_pass();
161	}
162
163	waitpid(pid2, &status, P_ALL);
164
165	return ksft_exit_pass();
166}
167