1 /*
2 * Copyright (c) 2002, Intel Corporation. All rights reserved.
3 * This file is licensed under the GPL license. For the full content
4 * of this license, see the COPYING file at the top level of this
5 * source tree.
6 *
7 * The munmap() function shall remove any mappings for those
8 * entire pages containing any part of the address space of
9 * the process starting at addr and continuing for len bytes.
10 * Further references to these pages shall result in the
11 * generation of a SIGSEGV signal to the process.
12 *
13 * Test Step:
14 * 1. map a file into memory;
15 * 2. unmap;
16 * 3. Try to reference the unmapped memory, test whether SIGSEGV
17 * is triggered.
18 */
19
20 #define _XOPEN_SOURCE 600
21
22 #include <sys/mman.h>
23 #include <sys/types.h>
24 #include <sys/stat.h>
25 #include <sys/wait.h>
26 #include <errno.h>
27 #include <fcntl.h>
28 #include <pthread.h>
29 #include <signal.h>
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <string.h>
33 #include <unistd.h>
34 #include "posixtest.h"
35
36 #define TNAME "munmap/1-2.c"
37
sigsegv_handler(int signum)38 void sigsegv_handler(int signum)
39 {
40 printf("Got SIGSEGV\n");
41 printf("Test PASSED\n");
42 exit(PTS_PASS);
43 }
44
main(void)45 int main(void)
46 {
47 char tmpfname[256];
48 long file_size;
49
50 void *pa = NULL;
51 void *addr = NULL;
52 size_t len;
53 int flag;
54 int fd;
55 off_t off = 0;
56 int prot;
57
58 int page_size;
59
60 char *ch;
61
62 struct sigaction sa;
63
64 sigfillset(&sa.sa_mask);
65 sa.sa_handler = sigsegv_handler;
66 sigaction(SIGSEGV, &sa, NULL);
67
68 page_size = sysconf(_SC_PAGE_SIZE);
69 file_size = 2 * page_size;
70
71 /* We hope to map 2 pages */
72 len = page_size + 1;
73
74 /* Create tmp file */
75 snprintf(tmpfname, sizeof(tmpfname), "/tmp/pts_munmap_1_1_%d",
76 getpid());
77 unlink(tmpfname);
78 fd = open(tmpfname, O_CREAT | O_RDWR | O_EXCL, S_IRUSR | S_IWUSR);
79 if (fd == -1) {
80 printf(TNAME " Error at open(): %s\n", strerror(errno));
81 exit(PTS_UNRESOLVED);
82 }
83 unlink(tmpfname);
84
85 if (ftruncate(fd, file_size) == -1) {
86 printf("Error at ftruncate: %s\n", strerror(errno));
87 exit(PTS_UNRESOLVED);
88 }
89
90 flag = MAP_SHARED;
91 prot = PROT_READ | PROT_WRITE;
92 pa = mmap(addr, len, prot, flag, fd, off);
93 if (pa == MAP_FAILED) {
94 printf("Test UNRESOLVED: " TNAME " Error at mmap: %s\n",
95 strerror(errno));
96 exit(PTS_UNRESOLVED);
97 }
98
99 ch = pa;
100 *ch = 'b';
101
102 close(fd);
103 munmap(pa, len);
104
105 /* Should trigger SIGSEGV here */
106 *ch = 'a';
107
108 printf("Test FAILED: Did not trigger SIGSEGV\n");
109 return PTS_FAIL;
110 }
111