1 // Regression test for 2 // http://code.google.com/p/address-sanitizer/issues/detail?id=19 3 // Bug description: 4 // 1. application dlopens foo.so 5 // 2. asan registers all globals from foo.so 6 // 3. application dlcloses foo.so 7 // 4. application mmaps some memory to the location where foo.so was before 8 // 5. application starts using this mmaped memory, but asan still thinks there 9 // are globals. 10 // 6. BOOM 11 12 // This subtle test assumes that after a foo.so is dlclose-d 13 // we can mmap the region of memory that was occupied by the library. 14 // This test works on x86 and Darwin, but not confirmed working anywhere else. 15 // REQUIRES: x86-target-arch || darwin 16 17 // RUN: %clangxx_asan -O0 -DSHARED_LIB %s -fPIC -shared -o %t-so.so 18 // RUN: %clangxx_asan -O0 %s %libdl -o %t && %run %t 2>&1 | FileCheck %s 19 // RUN: %clangxx_asan -O1 -DSHARED_LIB %s -fPIC -shared -o %t-so.so 20 // RUN: %clangxx_asan -O1 %s %libdl -o %t && %run %t 2>&1 | FileCheck %s 21 // RUN: %clangxx_asan -O2 -DSHARED_LIB %s -fPIC -shared -o %t-so.so 22 // RUN: %clangxx_asan -O2 %s %libdl -o %t && %run %t 2>&1 | FileCheck %s 23 // RUN: %clangxx_asan -O3 -DSHARED_LIB %s -fPIC -shared -o %t-so.so 24 // RUN: %clangxx_asan -O3 %s %libdl -o %t && %run %t 2>&1 | FileCheck %s 25 26 // XFAIL: i386-netbsd 27 28 #if !defined(SHARED_LIB) 29 #include <assert.h> 30 #include <dlfcn.h> 31 #include <stdio.h> 32 #include <string.h> 33 #include <sys/mman.h> 34 #include <unistd.h> 35 36 #include <string> 37 38 #if defined(__FreeBSD__) 39 // The MAP_NORESERVE define has been removed in FreeBSD 11.x, and even before 40 // that, it was never implemented. So just define it to zero. 41 #undef MAP_NORESERVE 42 #define MAP_NORESERVE 0 43 #endif 44 45 using std::string; 46 47 typedef int *(fun_t)(); 48 49 int main(int argc, char *argv[]) { 50 string path = string(argv[0]) + "-so.so"; 51 size_t PageSize = sysconf(_SC_PAGESIZE); 52 printf("opening %s ... \n", path.c_str()); 53 void *lib = dlopen(path.c_str(), RTLD_NOW); 54 if (!lib) { 55 printf("error in dlopen(): %s\n", dlerror()); 56 return 1; 57 } 58 fun_t *get = (fun_t*)dlsym(lib, "get_address_of_static_var"); 59 if (!get) { 60 printf("failed dlsym\n"); 61 return 1; 62 } 63 int *addr = get(); 64 assert(((size_t)addr % 32) == 0); // should be 32-byte aligned. 65 printf("addr: %p\n", addr); 66 addr[0] = 1; // make sure we can write there. 67 68 // Now dlclose the shared library. 69 printf("attempting to dlclose\n"); 70 if (dlclose(lib)) { 71 printf("failed to dlclose\n"); 72 return 1; 73 } 74 // Now, the page where 'addr' is unmapped. Map it. 75 size_t page_beg = ((size_t)addr) & ~(PageSize - 1); 76 void *res = mmap((void*)(page_beg), PageSize, 77 PROT_READ | PROT_WRITE, 78 MAP_PRIVATE | MAP_ANON | MAP_FIXED | MAP_NORESERVE, -1, 0); 79 if (res == (char*)-1L) { 80 printf("failed to mmap\n"); 81 return 1; 82 } 83 addr[1] = 2; // BOOM (if the bug is not fixed). 84 printf("PASS\n"); 85 // CHECK: PASS 86 return 0; 87 } 88 #else // SHARED_LIB 89 #include <stdio.h> 90 91 static int pad1; 92 static int static_var; 93 static int pad2; 94 95 extern "C" 96 int *get_address_of_static_var() { 97 return &static_var; 98 } 99 100 __attribute__((constructor)) 101 void at_dlopen() { 102 printf("%s: I am being dlopened\n", __FILE__); 103 } 104 __attribute__((destructor)) 105 void at_dlclose() { 106 printf("%s: I am being dlclosed\n", __FILE__); 107 } 108 #endif // SHARED_LIB 109