summary refs log tree commit diff
path: root/elf/nodelete.c
blob: f8abe1ff9f90945fc78c84f7658d010038212612 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
#include <dlfcn.h>
#include <setjmp.h>
#include <signal.h>
#include <stdio.h>


static sigjmp_buf jmpbuf;


static void
handler (int sig)
{
  siglongjmp (jmpbuf, 1);
}


#define TEST_FUNCTION do_test ()
static int
do_test (void)
{
  /* We are testing the two possibilities to mark an object as not deletable:
     - marked on the linker commandline with `-z nodelete'
     - with the RTLD_NODELETE flag at dlopen()-time.

     The test we are performing should be safe.  We are loading the objects,
     get the address of variables in the respective object, unload the object
     and then try to read the variable.  If the object is unloaded this
     should lead to an segmentation fault.  */
  int result = 0;
  void *p;
  struct sigaction sa;

  sa.sa_handler = handler;
  sigfillset (&sa.sa_mask);
  sa.sa_flags = SA_RESTART;

  if (sigaction (SIGSEGV, &sa, NULL) == -1)
    printf ("cannot install signal handler: %m\n");

  p = dlopen ("nodelmod1.so", RTLD_LAZY);
  if (p == NULL)
    {
      printf ("failed to load \"nodelmod1.so\": %s\n", dlerror ());
      result = 1;
    }
  else
    {
      int *varp;

      puts ("succeeded loading \"nodelmod1.so\"");

      varp = dlsym (p, "var1");
      if (varp == NULL)
	{
	  puts ("failed to get address of \"var1\" in \"nodelmod1.so\"");
	  result = 1;
	}
      else
	{
	  *varp = 20000720;

	  /* Now close the object.  */
	  if (dlclose (p) != 0)
	    {
	      puts ("failed to close \"nodelmod1.so\"");
	      result = 1;
	    }
	  else if (! sigsetjmp (jmpbuf, 1))
	    {
	      /* Access the variable again.  */
	      if (*varp != 20000720)
		{
		  puts ("\"var1\" value not correct");
		  result = 1;
		}
	      else
		puts ("-z nodelete test succeeded");
	    }
	  else
	    {
	      /* We caught an segmentation fault.  */
	      puts ("\"nodelmod1.so\" got deleted");
	      result = 1;
	    }
	}
    }

  p = dlopen ("nodelmod2.so", RTLD_LAZY | RTLD_NODELETE);
  if (p == NULL)
    {
      printf ("failed to load \"nodelmod2.so\": %s\n", dlerror ());
      result = 1;
    }
  else
    {
      int *varp;

      puts ("succeeded loading \"nodelmod2.so\"");

      varp = dlsym (p, "var2");
      if (varp == NULL)
	{
	  puts ("failed to get address of \"var2\" in \"nodelmod2.so\"");
	  result = 1;
	}
      else
	{
	  *varp = 42;

	  /* Now close the object.  */
	  if (dlclose (p) != 0)
	    {
	      puts ("failed to close \"nodelmod2.so\"");
	      result = 1;
	    }
	  else if (! sigsetjmp (jmpbuf, 1))
	    {
	      /* Access the variable again.  */
	      if (*varp != 42)
		{
		  puts ("\"var2\" value not correct");
		  result = 1;
		}
	      else
		puts ("RTLD_NODELETE test succeeded");
	    }
	  else
	    {
	      /* We caught an segmentation fault.  */
	      puts ("\"nodelmod2.so\" got deleted");
	      result = 1;
	    }
	}
    }

  p = dlopen ("nodelmod3.so", RTLD_LAZY);
  if (p == NULL)
    {
      printf ("failed to load \"nodelmod3.so\": %s\n", dlerror ());
      result = 1;
    }
  else
    {
      int *(*fctp) (void);

      puts ("succeeded loading \"nodelmod3.so\"");

      fctp = dlsym (p, "addr");
      if (fctp == NULL)
	{
	  puts ("failed to get address of \"addr\" in \"nodelmod3.so\"");
	  result = 1;
	}
      else
	{
	  int *varp = fctp ();

	  *varp = -1;

	  /* Now close the object.  */
	  if (dlclose (p) != 0)
	    {
	      puts ("failed to close \"nodelmod3.so\"");
	      result = 1;
	    }
	  else if (! sigsetjmp (jmpbuf, 1))
	    {
	      /* Access the variable again.  */
	      if (*varp != -1)
		{
		  puts ("\"var_in_mod4\" value not correct");
		  result = 1;
		}
	      else
		puts ("-z nodelete in dependency succeeded");
	    }
	  else
	    {
	      /* We caught an segmentation fault.  */
	      puts ("\"nodelmod4.so\" got deleted");
	      result = 1;
	    }
	}
    }

  return result;
}

#include "../test-skeleton.c"