xref: /aosp_15_r20/external/ltp/testcases/kernel/syscalls/ipc/shmdt/shmdt01.c (revision 49cdfc7efb34551c7342be41a7384b9c40d7cab7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) International Business Machines Corp., 2001
4  */
5 
6 /*\
7  * [Description]
8  *
9  * This case check whether we get SIGSEGV when write a value to a detached
10  * shared memory resource.
11  */
12 
13 #include <sys/types.h>
14 #include <sys/ipc.h>
15 #include <sys/shm.h>
16 #include <setjmp.h>
17 #include "tst_test.h"
18 #include "libnewipc.h"
19 #include "tst_safe_sysv_ipc.h"
20 
21 static int shm_id = -1, shm_key, pass;
22 static int *shared;
23 static sigjmp_buf env;
24 
sighandler(int sig LTP_ATTRIBUTE_UNUSED)25 static void sighandler(int sig LTP_ATTRIBUTE_UNUSED)
26 {
27 	pass = 1;
28 	siglongjmp(env, 1);
29 }
30 
check_functionality(void)31 static void check_functionality(void)
32 {
33 	struct shmid_ds buf;
34 
35 	SAFE_SHMCTL(shm_id, IPC_STAT, &buf);
36 	TST_EXP_EQ_LI(buf.shm_nattch, 0);
37 	if (buf.shm_nattch)
38 		return;
39 
40 	if (sigsetjmp(env, 1) == 0)
41 		*shared = 2;
42 
43 	if (pass)
44 		tst_res(TPASS, "shared memory detached correctly");
45 	else
46 		tst_res(TFAIL, "shared memory was not detached correctly");
47 }
48 
verify_shmdt(void)49 static void verify_shmdt(void)
50 {
51 	TST_EXP_PASS_SILENT(shmdt(shared));
52 	if (TST_PASS) {
53 		check_functionality();
54 		shared = SAFE_SHMAT(shm_id, 0, 0);
55 	}
56 
57 	pass = 0;
58 }
59 
setup(void)60 static void setup(void)
61 {
62 	shm_key = GETIPCKEY();
63 	shm_id = SAFE_SHMGET(shm_key, INT_SIZE, SHM_RW | IPC_CREAT | IPC_EXCL);
64 
65 	SAFE_SIGNAL(SIGSEGV, sighandler);
66 	shared = SAFE_SHMAT(shm_id, 0, 0);
67 }
68 
cleanup(void)69 static void cleanup(void)
70 {
71 	if (shm_id != -1)
72 		SAFE_SHMCTL(shm_id, IPC_RMID, NULL);
73 }
74 
75 static struct tst_test test = {
76 	.needs_tmpdir = 1,
77 	.needs_root = 1,
78 	.setup = setup,
79 	.cleanup = cleanup,
80 	.test_all = verify_shmdt,
81 };
82