xref: /aosp_15_r20/external/ltp/testcases/kernel/syscalls/modify_ldt/modify_ldt01.c (revision 49cdfc7efb34551c7342be41a7384b9c40d7cab7)
1 /*
2  *
3  *   Copyright (c) International Business Machines  Corp., 2001
4  *
5  *   This program is free software;  you can redistribute it and/or modify
6  *   it under the terms of the GNU General Public License as published by
7  *   the Free Software Foundation; either version 2 of the License, or
8  *   (at your option) any later version.
9  *
10  *   This program is distributed in the hope that it will be useful,
11  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
13  *   the GNU General Public License for more details.
14  *
15  *   You should have received a copy of the GNU General Public License
16  *   along with this program;  if not, write to the Free Software
17  *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18  */
19 
20 /*
21  * NAME
22  *	modify_ldt01.c
23  *
24  * DESCRIPTION
25  *	Testcase to check the error conditions for modify_ldt(2)
26  *
27  * CALLS
28  *	modify_ldt()
29  *
30  * ALGORITHM
31  *	block1:
32  *		Invoke modify_ldt() with a func value which is neither
33  *		0 or 1. Verify that ENOSYS is set.
34  *	block2:
35  *		Invoke mprotect() with ptr == NULL. Verify that EINVAL
36  *		is set.
37  *	block3:
38  *		Create an LDT segment.
39  *		Try to read from an invalid pointer.
40  *		Verify that EFAULT is set.
41  *
42  * USAGE
43  *	modify_ldt01
44  *
45  * HISTORY
46  *	07/2001 Ported by Wayne Boyer
47  *
48  * RESTRICTIONS
49  *	None
50  */
51 
52 #include "config.h"
53 #include "test.h"
54 
55 TCID_DEFINE(modify_ldt01);
56 int TST_TOTAL = 1;
57 
58 #if defined(__i386__) && defined(HAVE_MODIFY_LDT)
59 
60 #ifdef HAVE_ASM_LDT_H
61 #include <asm/ldt.h>
62 #endif
63 extern int modify_ldt(int, void *, unsigned long);
64 
65 #include <asm/unistd.h>
66 #include <errno.h>
67 
68 /* Newer ldt.h files use user_desc, instead of modify_ldt_ldt_s */
69 #ifdef HAVE_STRUCT_USER_DESC
70 typedef struct user_desc modify_ldt_s;
71 #elif  HAVE_STRUCT_MODIFY_LDT_LDT_S
72 typedef struct modify_ldt_ldt_s modify_ldt_s;
73 #else
74 typedef struct modify_ldt_ldt_t {
75 	unsigned int entry_number;
76 	unsigned long int base_addr;
77 	unsigned int limit;
78 	unsigned int seg_32bit:1;
79 	unsigned int contents:2;
80 	unsigned int read_exec_only:1;
81 	unsigned int limit_in_pages:1;
82 	unsigned int seg_not_present:1;
83 	unsigned int useable:1;
84 	unsigned int empty:25;
85 } modify_ldt_s;
86 #endif
87 
88 int create_segment(void *, size_t);
89 void cleanup(void);
90 void setup(void);
91 
main(int ac,char ** av)92 int main(int ac, char **av)
93 {
94 	int lc;
95 
96 	void *ptr;
97 	int retval, func;
98 
99 	int seg[4];
100 
101 	tst_parse_opts(ac, av, NULL, NULL);
102 
103 	setup();
104 
105 	for (lc = 0; TEST_LOOPING(lc); lc++) {
106 
107 		/* reset tst_count in case we are looping */
108 		tst_count = 0;
109 
110 		/*
111 		 * Check for ENOSYS.
112 		 */
113 		ptr = malloc(10);
114 		func = 100;
115 		retval = modify_ldt(func, ptr, sizeof(ptr));
116 		if (retval < 0) {
117 			if (errno != ENOSYS) {
118 				tst_resm(TFAIL, "modify_ldt() set invalid "
119 					 "errno, expected ENOSYS, got: %d",
120 					 errno);
121 			} else {
122 				tst_resm(TPASS,
123 					"modify_ldt() set expected errno");
124 			}
125 		} else {
126 			tst_resm(TFAIL, "modify_ldt error: "
127 				 "unexpected return value %d", retval);
128 		}
129 
130 		free(ptr);
131 
132 		/*
133 		 * Check for EINVAL
134 		 */
135 		ptr = 0;
136 
137 		retval = modify_ldt(1, ptr, sizeof(ptr));
138 		if (retval < 0) {
139 			if (errno != EINVAL) {
140 				tst_resm(TFAIL, "modify_ldt() set invalid "
141 					 "errno, expected EINVAL, got: %d",
142 					 errno);
143 			} else {
144 				tst_resm(TPASS,
145 					"modify_ldt() set expected errno");
146 			}
147 		} else {
148 			tst_resm(TFAIL, "modify_ldt error: "
149 				 "unexpected return value %d", retval);
150 		}
151 
152 		/*
153 		 * Create a new LDT segment.
154 		 */
155 		if (create_segment(seg, sizeof(seg)) == -1) {
156 			tst_brkm(TBROK, cleanup, "Creation of segment failed");
157 		}
158 
159 		/*
160 		 * Check for EFAULT
161 		 */
162 		ptr = sbrk(0);
163 
164 		retval = modify_ldt(0, ptr + 0xFFF, sizeof(ptr));
165 		if (retval < 0) {
166 			if (errno != EFAULT) {
167 				tst_resm(TFAIL, "modify_ldt() set invalid "
168 					 "errno, expected EFAULT, got: %d",
169 					 errno);
170 			} else {
171 				tst_resm(TPASS,
172 					"modify_ldt() set expected errno");
173 			}
174 		} else {
175 			tst_resm(TFAIL, "modify_ldt error: "
176 				 "unexpected return value %d", retval);
177 		}
178 	}
179 	cleanup();
180 	tst_exit();
181 }
182 
183 /*
184  * create_segment() -
185  */
create_segment(void * seg,size_t size)186 int create_segment(void *seg, size_t size)
187 {
188 	modify_ldt_s entry;
189 
190 	entry.entry_number = 0;
191 	entry.base_addr = (unsigned long)seg;
192 	entry.limit = size;
193 	entry.seg_32bit = 1;
194 	entry.contents = 0;
195 	entry.read_exec_only = 0;
196 	entry.limit_in_pages = 0;
197 	entry.seg_not_present = 0;
198 
199 	return modify_ldt(1, &entry, sizeof(entry));
200 }
201 
setup(void)202 void setup(void)
203 {
204 
205 	tst_sig(FORK, DEF_HANDLER, cleanup);
206 
207 	TEST_PAUSE;
208 }
209 
cleanup(void)210 void cleanup(void)
211 {
212 
213 }
214 
215 #elif HAVE_MODIFY_LDT
main(void)216 int main(void)
217 {
218 	tst_brkm(TCONF,
219 		 NULL,
220 		 "modify_ldt is available but not tested on the platform than __i386__");
221 }
222 
223 #else
main(void)224 int main(void)
225 {
226 	tst_resm(TINFO, "modify_ldt01 test only for ix86");
227 	tst_exit();
228 }
229 
230 #endif /* defined(__i386__) */
231