1#define _GNU_SOURCE
2#include <stdio.h>
3#include <signal.h>
4#include <unistd.h>
5#include <errno.h>
6#include <linux/types.h>
7#include <sys/wait.h>
8#include <sys/syscall.h>
9#include <sys/user.h>
10#include <sys/mman.h>
11
12#include "linux/ptrace.h"
13
14static int sys_rt_sigqueueinfo(pid_t tgid, int sig, siginfo_t *uinfo)
15{
16	return syscall(SYS_rt_sigqueueinfo, tgid, sig, uinfo);
17}
18
19static int sys_rt_tgsigqueueinfo(pid_t tgid, pid_t tid,
20					int sig, siginfo_t *uinfo)
21{
22	return syscall(SYS_rt_tgsigqueueinfo, tgid, tid, sig, uinfo);
23}
24
25static int sys_ptrace(int request, pid_t pid, void *addr, void *data)
26{
27	return syscall(SYS_ptrace, request, pid, addr, data);
28}
29
30#define SIGNR 10
31#define TEST_SICODE_PRIV	-1
32#define TEST_SICODE_SHARE	-2
33
34#ifndef PAGE_SIZE
35#define PAGE_SIZE sysconf(_SC_PAGESIZE)
36#endif
37
38#define err(fmt, ...)						\
39		fprintf(stderr,					\
40			"Error (%s:%d): " fmt,			\
41			__FILE__, __LINE__, ##__VA_ARGS__)
42
43static int check_error_paths(pid_t child)
44{
45	struct ptrace_peeksiginfo_args arg;
46	int ret, exit_code = -1;
47	void *addr_rw, *addr_ro;
48
49	/*
50	 * Allocate two contiguous pages. The first one is for read-write,
51	 * another is for read-only.
52	 */
53	addr_rw = mmap(NULL, 2 * PAGE_SIZE, PROT_READ | PROT_WRITE,
54				MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
55	if (addr_rw == MAP_FAILED) {
56		err("mmap() failed: %m\n");
57		return 1;
58	}
59
60	addr_ro = mmap(addr_rw + PAGE_SIZE, PAGE_SIZE, PROT_READ,
61			MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
62	if (addr_ro == MAP_FAILED) {
63		err("mmap() failed: %m\n");
64		goto out;
65	}
66
67	arg.nr = SIGNR;
68	arg.off = 0;
69
70	/* Unsupported flags */
71	arg.flags = ~0;
72	ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, addr_rw);
73	if (ret != -1 || errno != EINVAL) {
74		err("sys_ptrace() returns %d (expected -1),"
75				" errno %d (expected %d): %m\n",
76				ret, errno, EINVAL);
77		goto out;
78	}
79	arg.flags = 0;
80
81	/* A part of the buffer is read-only */
82	ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg,
83					addr_ro - sizeof(siginfo_t) * 2);
84	if (ret != 2) {
85		err("sys_ptrace() returns %d (expected 2): %m\n", ret);
86		goto out;
87	}
88
89	/* Read-only buffer */
90	ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, addr_ro);
91	if (ret != -1 && errno != EFAULT) {
92		err("sys_ptrace() returns %d (expected -1),"
93				" errno %d (expected %d): %m\n",
94				ret, errno, EFAULT);
95		goto out;
96	}
97
98	exit_code = 0;
99out:
100	munmap(addr_rw, 2 * PAGE_SIZE);
101	return exit_code;
102}
103
104int check_direct_path(pid_t child, int shared, int nr)
105{
106	struct ptrace_peeksiginfo_args arg = {.flags = 0, .nr = nr, .off = 0};
107	int i, j, ret, exit_code = -1;
108	siginfo_t siginfo[SIGNR];
109	int si_code;
110
111	if (shared == 1) {
112		arg.flags = PTRACE_PEEKSIGINFO_SHARED;
113		si_code = TEST_SICODE_SHARE;
114	} else {
115		arg.flags = 0;
116		si_code = TEST_SICODE_PRIV;
117	}
118
119	for (i = 0; i < SIGNR; ) {
120		arg.off = i;
121		ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, siginfo);
122		if (ret == -1) {
123			err("ptrace() failed: %m\n");
124			goto out;
125		}
126
127		if (ret == 0)
128			break;
129
130		for (j = 0; j < ret; j++, i++) {
131			if (siginfo[j].si_code == si_code &&
132			    siginfo[j].si_int == i)
133				continue;
134
135			err("%d: Wrong siginfo i=%d si_code=%d si_int=%d\n",
136			     shared, i, siginfo[j].si_code, siginfo[j].si_int);
137			goto out;
138		}
139	}
140
141	if (i != SIGNR) {
142		err("Only %d signals were read\n", i);
143		goto out;
144	}
145
146	exit_code = 0;
147out:
148	return exit_code;
149}
150
151int main(int argc, char *argv[])
152{
153	siginfo_t siginfo[SIGNR];
154	int i, exit_code = 1;
155	sigset_t blockmask;
156	pid_t child;
157
158	sigemptyset(&blockmask);
159	sigaddset(&blockmask, SIGRTMIN);
160	sigprocmask(SIG_BLOCK, &blockmask, NULL);
161
162	child = fork();
163	if (child == -1) {
164		err("fork() failed: %m");
165		return 1;
166	} else if (child == 0) {
167		pid_t ppid = getppid();
168		while (1) {
169			if (ppid != getppid())
170				break;
171			sleep(1);
172		}
173		return 1;
174	}
175
176	/* Send signals in process-wide and per-thread queues */
177	for (i = 0; i < SIGNR; i++) {
178		siginfo->si_code = TEST_SICODE_SHARE;
179		siginfo->si_int = i;
180		sys_rt_sigqueueinfo(child, SIGRTMIN, siginfo);
181
182		siginfo->si_code = TEST_SICODE_PRIV;
183		siginfo->si_int = i;
184		sys_rt_tgsigqueueinfo(child, child, SIGRTMIN, siginfo);
185	}
186
187	if (sys_ptrace(PTRACE_ATTACH, child, NULL, NULL) == -1)
188		return 1;
189
190	waitpid(child, NULL, 0);
191
192	/* Dump signals one by one*/
193	if (check_direct_path(child, 0, 1))
194		goto out;
195	/* Dump all signals for one call */
196	if (check_direct_path(child, 0, SIGNR))
197		goto out;
198
199	/*
200	 * Dump signal from the process-wide queue.
201	 * The number of signals is not multible to the buffer size
202	 */
203	if (check_direct_path(child, 1, 3))
204		goto out;
205
206	if (check_error_paths(child))
207		goto out;
208
209	printf("PASS\n");
210	exit_code = 0;
211out:
212	if (sys_ptrace(PTRACE_KILL, child, NULL, NULL) == -1)
213		return 1;
214
215	waitpid(child, NULL, 0);
216
217	return exit_code;
218}
219