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
sys_rt_sigqueueinfo(pid_t tgid,int sig,siginfo_t * uinfo)15 static int sys_rt_sigqueueinfo(pid_t tgid, int sig, siginfo_t *uinfo)
16 {
17 return syscall(SYS_rt_sigqueueinfo, tgid, sig, uinfo);
18 }
19
sys_rt_tgsigqueueinfo(pid_t tgid,pid_t tid,int sig,siginfo_t * uinfo)20 static 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
sys_ptrace(int request,pid_t pid,void * addr,void * data)26 static 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
check_error_paths(pid_t child)44 static 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;
100 out:
101 munmap(addr_rw, 2 * PAGE_SIZE);
102 return exit_code;
103 }
104
check_direct_path(pid_t child,int shared,int nr)105 int 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;
148 out:
149 return exit_code;
150 }
151
main(int argc,char * argv[])152 int main(int argc, char *argv[])
153 {
154 siginfo_t siginfo[SIGNR];
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;
212 out:
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