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1 // Regression test for a bug in malloc_create_zone()
2 // (https://code.google.com/p/address-sanitizer/issues/detail?id=203)
3 // The old implementation of malloc_create_zone() didn't always return a
4 // page-aligned address, so we can only test on a best-effort basis.
5 
6 // RUN: %clangxx_asan %s -o %t
7 // RUN: %run %t 2>&1
8 
9 #include <malloc/malloc.h>
10 #include <stdlib.h>
11 #include <string.h>
12 #include <stdio.h>
13 
14 const int kNumIter = 4096;
15 const int kNumZones = 100;
main()16 int main() {
17   char *mem[kNumIter * 2];
18   // Allocate memory chunks from different size classes up to 1 page.
19   // (For the case malloc() returns memory chunks in descending order)
20   for (int i = 0; i < kNumIter; i++) {
21     mem[i] = (char*)malloc(8 * i);
22   }
23   // Try to allocate a page-aligned malloc zone. Otherwise the mprotect() call
24   // in malloc_set_zone_name() will silently fail.
25   malloc_zone_t *zone = NULL;
26   bool aligned = false;
27   for (int i = 0; i < kNumZones; i++) {
28     zone = malloc_create_zone(0, 0);
29     if (((uintptr_t)zone & (~0xfff)) == (uintptr_t)zone) {
30       aligned = true;
31       break;
32     }
33   }
34   if (!aligned) {
35     printf("Warning: couldn't allocate a page-aligned zone.");
36     return 0;
37   }
38   // malloc_set_zone_name() calls mprotect(zone, 4096, PROT_READ | PROT_WRITE),
39   // modifies the zone contents and then calls mprotect(zone, 4096, PROT_READ).
40   malloc_set_zone_name(zone, "foobar");
41   // Allocate memory chunks from different size classes again.
42   for (int i = 0; i < kNumIter; i++) {
43     mem[i + kNumIter] = (char*)malloc(8 * i);
44   }
45   // Access the allocated memory chunks and free them.
46   for (int i = 0; i < kNumIter * 2; i++) {
47     memset(mem[i], 'a', 8 * (i % kNumIter));
48     free(mem[i]);
49   }
50   return 0;
51 }
52