1 // RUN: %clangxx_scudo %s -lstdc++ -o %t 2 // RUN: %run %t pointers 2>&1 3 // RUN: %run %t contents 2>&1 4 // RUN: %run %t usablesize 2>&1 5 6 // Tests that our reallocation function returns the same pointer when the 7 // requested size can fit into the previously allocated chunk. Also tests that 8 // a new chunk is returned if the size is greater, and that the contents of the 9 // chunk are left unchanged. Finally, checks that realloc copies the usable 10 // size of the old chunk to the new one (as opposed to the requested size). 11 12 #include <assert.h> 13 #include <malloc.h> 14 #include <string.h> 15 16 #include <vector> 17 18 #include <sanitizer/allocator_interface.h> 19 20 int main(int argc, char **argv) 21 { 22 void *p, *old_p; 23 // Those sizes will exercise both allocators (Primary & Secondary). 24 std::vector<size_t> sizes{1, 16, 1024, 32768, 1 << 16, 1 << 17, 1 << 20}; 25 26 assert(argc == 2); 27 28 if (!strcmp(argv[1], "usablesize")) { 29 // This tests a sketchy behavior inherited from poorly written libraries 30 // that have become somewhat standard. When realloc'ing a chunk, the 31 // copied contents should span the usable size of the chunk, not the 32 // requested size. 33 size_t size = 496, usable_size; 34 p = nullptr; 35 // Make sure we get a chunk with a usable size actually larger than size. 36 do { 37 if (p) free(p); 38 size += 16; 39 p = malloc(size); 40 usable_size = __sanitizer_get_allocated_size(p); 41 assert(usable_size >= size); 42 } while (usable_size == size); 43 for (int i = 0; i < usable_size; i++) 44 reinterpret_cast<char *>(p)[i] = 'A'; 45 old_p = p; 46 // Make sure we get a different chunk so that the data is actually copied. 47 do { 48 size *= 2; 49 p = realloc(p, size); 50 assert(p); 51 } while (p == old_p); 52 // The contents of the new chunk must match the old one up to usable_size. 53 for (int i = 0; i < usable_size; i++) 54 assert(reinterpret_cast<char *>(p)[i] == 'A'); 55 free(p); 56 } else { 57 for (size_t size : sizes) { 58 if (!strcmp(argv[1], "pointers")) { 59 old_p = p = realloc(nullptr, size); 60 assert(p); 61 size = __sanitizer_get_allocated_size(p); 62 // Our realloc implementation will return the same pointer if the size 63 // requested is lower than or equal to the usable size of the associated 64 // chunk. 65 p = realloc(p, size - 1); 66 assert(p == old_p); 67 p = realloc(p, size); 68 assert(p == old_p); 69 // And a new one if the size is greater. 70 p = realloc(p, size + 1); 71 assert(p != old_p); 72 // A size of 0 will free the chunk and return nullptr. 73 p = realloc(p, 0); 74 assert(!p); 75 old_p = nullptr; 76 } 77 if (!strcmp(argv[1], "contents")) { 78 p = realloc(nullptr, size); 79 assert(p); 80 for (int i = 0; i < size; i++) 81 reinterpret_cast<char *>(p)[i] = 'A'; 82 p = realloc(p, size + 1); 83 // The contents of the reallocated chunk must match the original one. 84 for (int i = 0; i < size; i++) 85 assert(reinterpret_cast<char *>(p)[i] == 'A'); 86 } 87 } 88 } 89 return 0; 90 } 91 92 // CHECK: ERROR: invalid chunk type when reallocating address 93