• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 
21 #include <sys/mman.h>
22 #include <sys/types.h>
23 #include <sys/stat.h>
24 #include <sys/wait.h>
25 #include <errno.h>
26 #include <fcntl.h>
27 #include <pthread.h>
28 #include <signal.h>
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <unistd.h>
33 #include "posixtest.h"
34 
35 #define TNAME "munmap/1-2.c"
36 
sigsegv_handler(int signum LTP_ATTRIBUTE_UNUSED)37 void sigsegv_handler(int signum LTP_ATTRIBUTE_UNUSED)
38 {
39 	printf("Got SIGSEGV\n");
40 	printf("Test PASSED\n");
41 	exit(PTS_PASS);
42 }
43 
main(void)44 int main(void)
45 {
46 	char tmpfname[256];
47 	long file_size;
48 
49 	void *pa = NULL;
50 	void *addr = NULL;
51 	size_t len;
52 	int flag;
53 	int fd;
54 	off_t off = 0;
55 	int prot;
56 
57 	int page_size;
58 
59 	char *ch;
60 
61 	struct sigaction sa;
62 
63 	sigfillset(&sa.sa_mask);
64 	sa.sa_handler = sigsegv_handler;
65 	sigaction(SIGSEGV, &sa, NULL);
66 
67 	page_size = sysconf(_SC_PAGE_SIZE);
68 	file_size = 2 * page_size;
69 
70 	/* We hope to map 2 pages */
71 	len = page_size + 1;
72 
73 	/* Create tmp file */
74 	snprintf(tmpfname, sizeof(tmpfname), "/tmp/pts_munmap_1_1_%d",
75 		 getpid());
76 	unlink(tmpfname);
77 	fd = open(tmpfname, O_CREAT | O_RDWR | O_EXCL, S_IRUSR | S_IWUSR);
78 	if (fd == -1) {
79 		printf(TNAME " Error at open(): %s\n", strerror(errno));
80 		exit(PTS_UNRESOLVED);
81 	}
82 	unlink(tmpfname);
83 
84 	if (ftruncate(fd, file_size) == -1) {
85 		printf("Error at ftruncate: %s\n", strerror(errno));
86 		exit(PTS_UNRESOLVED);
87 	}
88 
89 	flag = MAP_SHARED;
90 	prot = PROT_READ | PROT_WRITE;
91 	pa = mmap(addr, len, prot, flag, fd, off);
92 	if (pa == MAP_FAILED) {
93 		printf("Test UNRESOLVED: " TNAME " Error at mmap: %s\n",
94 		       strerror(errno));
95 		exit(PTS_UNRESOLVED);
96 	}
97 
98 	ch = pa;
99 	*ch = 'b';
100 
101 	close(fd);
102 	munmap(pa, len);
103 
104 	/* Should trigger SIGSEGV here */
105 	*ch = 'a';
106 
107 	printf("Test FAILED: Did not trigger SIGSEGV\n");
108 	return PTS_FAIL;
109 }
110