1// SPDX-License-Identifier: GPL-2.0
2#define _GNU_SOURCE
3#include <stdio.h>
4#include <signal.h>
5#include <unistd.h>
6#include <errno.h>
7#include <linux/types.h>
8#include <sys/wait.h>
9#include <sys/syscall.h>
10#include <sys/user.h>
11#include <sys/mman.h>
12
13#include "linux/ptrace.h"
14
15static int sys_rt_sigqueueinfo(pid_t tgid, int sig, siginfo_t *uinfo)
16{
17	return syscall(SYS_rt_sigqueueinfo, tgid, sig, uinfo);
18}
19
20static int sys_rt_tgsigqueueinfo(pid_t tgid, pid_t tid,
21					int sig, siginfo_t *uinfo)
22{
23	return syscall(SYS_rt_tgsigqueueinfo, tgid, tid, sig, uinfo);
24}
25
26static int sys_ptrace(int request, pid_t pid, void *addr, void *data)
27{
28	return syscall(SYS_ptrace, request, pid, addr, data);
29}
30
31#define SIGNR 10
32#define TEST_SICODE_PRIV	-1
33#define TEST_SICODE_SHARE	-2
34
35#ifndef PAGE_SIZE
36#define PAGE_SIZE sysconf(_SC_PAGESIZE)
37#endif
38
39#define err(fmt, ...)						\
40		fprintf(stderr,					\
41			"Error (%s:%d): " fmt,			\
42			__FILE__, __LINE__, ##__VA_ARGS__)
43
44static int check_error_paths(pid_t child)
45{
46	struct ptrace_peeksiginfo_args arg;
47	int ret, exit_code = -1;
48	void *addr_rw, *addr_ro;
49
50	/*
51	 * Allocate two contiguous pages. The first one is for read-write,
52	 * another is for read-only.
53	 */
54	addr_rw = mmap(NULL, 2 * PAGE_SIZE, PROT_READ | PROT_WRITE,
55				MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
56	if (addr_rw == MAP_FAILED) {
57		err("mmap() failed: %m\n");
58		return 1;
59	}
60
61	addr_ro = mmap(addr_rw + PAGE_SIZE, PAGE_SIZE, PROT_READ,
62			MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
63	if (addr_ro == MAP_FAILED) {
64		err("mmap() failed: %m\n");
65		goto out;
66	}
67
68	arg.nr = SIGNR;
69	arg.off = 0;
70
71	/* Unsupported flags */
72	arg.flags = ~0;
73	ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, addr_rw);
74	if (ret != -1 || errno != EINVAL) {
75		err("sys_ptrace() returns %d (expected -1),"
76				" errno %d (expected %d): %m\n",
77				ret, errno, EINVAL);
78		goto out;
79	}
80	arg.flags = 0;
81
82	/* A part of the buffer is read-only */
83	ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg,
84					addr_ro - sizeof(siginfo_t) * 2);
85	if (ret != 2) {
86		err("sys_ptrace() returns %d (expected 2): %m\n", ret);
87		goto out;
88	}
89
90	/* Read-only buffer */
91	ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, addr_ro);
92	if (ret != -1 && errno != EFAULT) {
93		err("sys_ptrace() returns %d (expected -1),"
94				" errno %d (expected %d): %m\n",
95				ret, errno, EFAULT);
96		goto out;
97	}
98
99	exit_code = 0;
100out:
101	munmap(addr_rw, 2 * PAGE_SIZE);
102	return exit_code;
103}
104
105int check_direct_path(pid_t child, int shared, int nr)
106{
107	struct ptrace_peeksiginfo_args arg = {.flags = 0, .nr = nr, .off = 0};
108	int i, j, ret, exit_code = -1;
109	siginfo_t siginfo[SIGNR];
110	int si_code;
111
112	if (shared == 1) {
113		arg.flags = PTRACE_PEEKSIGINFO_SHARED;
114		si_code = TEST_SICODE_SHARE;
115	} else {
116		arg.flags = 0;
117		si_code = TEST_SICODE_PRIV;
118	}
119
120	for (i = 0; i < SIGNR; ) {
121		arg.off = i;
122		ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, siginfo);
123		if (ret == -1) {
124			err("ptrace() failed: %m\n");
125			goto out;
126		}
127
128		if (ret == 0)
129			break;
130
131		for (j = 0; j < ret; j++, i++) {
132			if (siginfo[j].si_code == si_code &&
133			    siginfo[j].si_int == i)
134				continue;
135
136			err("%d: Wrong siginfo i=%d si_code=%d si_int=%d\n",
137			     shared, i, siginfo[j].si_code, siginfo[j].si_int);
138			goto out;
139		}
140	}
141
142	if (i != SIGNR) {
143		err("Only %d signals were read\n", i);
144		goto out;
145	}
146
147	exit_code = 0;
148out:
149	return exit_code;
150}
151
152int main(int argc, char *argv[])
153{
154	siginfo_t siginfo;
155	int i, exit_code = 1;
156	sigset_t blockmask;
157	pid_t child;
158
159	sigemptyset(&blockmask);
160	sigaddset(&blockmask, SIGRTMIN);
161	sigprocmask(SIG_BLOCK, &blockmask, NULL);
162
163	child = fork();
164	if (child == -1) {
165		err("fork() failed: %m");
166		return 1;
167	} else if (child == 0) {
168		pid_t ppid = getppid();
169		while (1) {
170			if (ppid != getppid())
171				break;
172			sleep(1);
173		}
174		return 1;
175	}
176
177	/* Send signals in process-wide and per-thread queues */
178	for (i = 0; i < SIGNR; i++) {
179		siginfo.si_code = TEST_SICODE_SHARE;
180		siginfo.si_int = i;
181		sys_rt_sigqueueinfo(child, SIGRTMIN, &siginfo);
182
183		siginfo.si_code = TEST_SICODE_PRIV;
184		siginfo.si_int = i;
185		sys_rt_tgsigqueueinfo(child, child, SIGRTMIN, &siginfo);
186	}
187
188	if (sys_ptrace(PTRACE_ATTACH, child, NULL, NULL) == -1)
189		return 1;
190
191	waitpid(child, NULL, 0);
192
193	/* Dump signals one by one*/
194	if (check_direct_path(child, 0, 1))
195		goto out;
196	/* Dump all signals for one call */
197	if (check_direct_path(child, 0, SIGNR))
198		goto out;
199
200	/*
201	 * Dump signal from the process-wide queue.
202	 * The number of signals is not multible to the buffer size
203	 */
204	if (check_direct_path(child, 1, 3))
205		goto out;
206
207	if (check_error_paths(child))
208		goto out;
209
210	printf("PASS\n");
211	exit_code = 0;
212out:
213	if (sys_ptrace(PTRACE_KILL, child, NULL, NULL) == -1)
214		return 1;
215
216	waitpid(child, NULL, 0);
217
218	return exit_code;
219}
220