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 sublte test assumes that after a foo.so is dlclose-d 13 // we can mmap the region of memory that has been occupied by the library. 14 // It works on i368/x86_64 Linux, but not necessary anywhere else. 15 // REQUIRES: x86_64-supported-target,i386-supported-target 16 17 // RUN: %clangxx_asan -O0 -DSHARED_LIB %s -fPIC -shared -o %t-so.so 18 // RUN: %clangxx_asan -O0 %s -ldl -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 -ldl -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 -ldl -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 -ldl -o %t && %run %t 2>&1 | FileCheck %s 25 26 #if !defined(SHARED_LIB) 27 #include <assert.h> 28 #include <dlfcn.h> 29 #include <stdio.h> 30 #include <string.h> 31 #include <sys/mman.h> 32 #include <unistd.h> 33 34 #include <string> 35 36 using std::string; 37 38 typedef int *(fun_t)(); 39 40 int main(int argc, char *argv[]) { 41 string path = string(argv[0]) + "-so.so"; 42 size_t PageSize = sysconf(_SC_PAGESIZE); 43 printf("opening %s ... \n", path.c_str()); 44 void *lib = dlopen(path.c_str(), RTLD_NOW); 45 if (!lib) { 46 printf("error in dlopen(): %s\n", dlerror()); 47 return 1; 48 } 49 fun_t *get = (fun_t*)dlsym(lib, "get_address_of_static_var"); 50 if (!get) { 51 printf("failed dlsym\n"); 52 return 1; 53 } 54 int *addr = get(); 55 assert(((size_t)addr % 32) == 0); // should be 32-byte aligned. 56 printf("addr: %p\n", addr); 57 addr[0] = 1; // make sure we can write there. 58 59 // Now dlclose the shared library. 60 printf("attempting to dlclose\n"); 61 if (dlclose(lib)) { 62 printf("failed to dlclose\n"); 63 return 1; 64 } 65 // Now, the page where 'addr' is unmapped. Map it. 66 size_t page_beg = ((size_t)addr) & ~(PageSize - 1); 67 void *res = mmap((void*)(page_beg), PageSize, 68 PROT_READ | PROT_WRITE, 69 MAP_PRIVATE | MAP_ANON | MAP_FIXED | MAP_NORESERVE, 0, 0); 70 if (res == (char*)-1L) { 71 printf("failed to mmap\n"); 72 return 1; 73 } 74 addr[1] = 2; // BOOM (if the bug is not fixed). 75 printf("PASS\n"); 76 // CHECK: PASS 77 return 0; 78 } 79 #else // SHARED_LIB 80 #include <stdio.h> 81 82 static int pad1; 83 static int static_var; 84 static int pad2; 85 86 extern "C" 87 int *get_address_of_static_var() { 88 return &static_var; 89 } 90 91 __attribute__((constructor)) 92 void at_dlopen() { 93 printf("%s: I am being dlopened\n", __FILE__); 94 } 95 __attribute__((destructor)) 96 void at_dlclose() { 97 printf("%s: I am being dlclosed\n", __FILE__); 98 } 99 #endif // SHARED_LIB 100
