mirror of git://sourceware.org/git/glibc.git
				
				
				
			
		
			
				
	
	
		
			134 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			134 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
| /* Test program for making nonexecutable stacks executable
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|    on load of a DSO that requires executable stacks.  */
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| 
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| #include <dlfcn.h>
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| #include <stdio.h>
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| #include <string.h>
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| #include <unistd.h>
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| #include <error.h>
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| 
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| static void
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| print_maps (void)
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| {
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| #if 0
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|   char *cmd = NULL;
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|   asprintf (&cmd, "cat /proc/%d/maps", getpid ());
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|   system (cmd);
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|   free (cmd);
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| #endif
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| }
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| 
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| static void deeper (void (*f) (void));
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| 
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| #if USE_PTHREADS
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| # include <pthread.h>
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| 
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| static void *
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| tryme_thread (void *f)
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| {
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|   (*((void (*) (void)) f)) ();
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| 
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|   return 0;
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| }
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| 
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| static pthread_barrier_t startup_barrier, go_barrier;
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| static void *
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| waiter_thread (void *arg)
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| {
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|   void **f = arg;
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|   pthread_barrier_wait (&startup_barrier);
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|   pthread_barrier_wait (&go_barrier);
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| 
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|   (*((void (*) (void)) *f)) ();
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| 
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|   return 0;
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| }
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| #endif
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| 
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| static int
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| do_test (void)
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| {
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|   static void *f;		/* Address of this is used in other threads. */
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| 
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| #if USE_PTHREADS
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|   /* Create some threads while stacks are nonexecutable.  */
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|   #define N 5
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|   pthread_t thr[N];
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| 
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|   pthread_barrier_init (&startup_barrier, NULL, N + 1);
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|   pthread_barrier_init (&go_barrier, NULL, N + 1);
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| 
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|   for (int i = 0; i < N; ++i)
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|     {
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|       int rc = pthread_create (&thr[i], NULL, &waiter_thread, &f);
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|       if (rc)
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| 	error (1, rc, "pthread_create");
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|     }
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| 
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|   /* Make sure they are all there using their stacks.  */
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|   pthread_barrier_wait (&startup_barrier);
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|   puts ("threads waiting");
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| #endif
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| 
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|   print_maps ();
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| 
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|   /* Loading this module should force stacks to become executable.  */
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|   void *h = dlopen ("tst-execstack-mod.so", RTLD_LAZY);
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|   if (h == NULL)
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|     {
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|       printf ("cannot load: %s\n", dlerror ());
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|       return 1;
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|     }
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| 
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|   f = dlsym (h, "tryme");
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|   if (f == NULL)
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|     {
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|       printf ("symbol not found: %s\n", dlerror ());
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|       return 1;
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|     }
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| 
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|   /* Test if that really made our stack executable.
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|      The `tryme' function should crash if not.  */
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| 
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|   (*((void (*) (void)) f)) ();
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| 
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|   print_maps ();
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| 
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|   /* Test that growing the stack region gets new executable pages too.  */
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|   deeper ((void (*) (void)) f);
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| 
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|   print_maps ();
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| 
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| #if USE_PTHREADS
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|   /* Test that a fresh thread now gets an executable stack.  */
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|   {
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|     pthread_t th;
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|     int rc = pthread_create (&th, NULL, &tryme_thread, f);
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|     if (rc)
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|       error (1, rc, "pthread_create");
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|   }
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| 
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|   puts ("threads go");
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|   /* The existing threads' stacks should have been changed.
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|      Let them run to test it.  */
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|   pthread_barrier_wait (&go_barrier);
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| 
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|   pthread_exit (0);
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| #endif
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| 
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|   return 0;
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| }
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| 
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| static void
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| deeper (void (*f) (void))
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| {
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|   char stack[1100 * 1024];
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|   memfrob (stack, sizeof stack);
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|   (*f) ();
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|   memfrob (stack, sizeof stack);
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| }
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| 
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| 
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| #define TEST_FUNCTION do_test ()
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| #include "../test-skeleton.c"
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