// Regression test for // http://code.google.com/p/address-sanitizer/issues/detail?id=19 // Bug description: // 1. application dlopens foo.so // 2. asan registers all globals from foo.so // 3. application dlcloses foo.so // 4. application mmaps some memory to the location where foo.so was before // 5. application starts using this mmaped memory, but asan still thinks there // are globals. // 6. BOOM // This sublte test assumes that after a foo.so is dlclose-d // we can mmap the region of memory that has been occupied by the library. // It works on x86 Linux, but not necessary anywhere else. // REQUIRES: x86-target-arch // RUN: %clangxx_asan -O0 -DSHARED_LIB %s -fPIC -shared -o %t-so.so // RUN: %clangxx_asan -O0 %s %libdl -o %t && %run %t 2>&1 | FileCheck %s // RUN: %clangxx_asan -O1 -DSHARED_LIB %s -fPIC -shared -o %t-so.so // RUN: %clangxx_asan -O1 %s %libdl -o %t && %run %t 2>&1 | FileCheck %s // RUN: %clangxx_asan -O2 -DSHARED_LIB %s -fPIC -shared -o %t-so.so // RUN: %clangxx_asan -O2 %s %libdl -o %t && %run %t 2>&1 | FileCheck %s // RUN: %clangxx_asan -O3 -DSHARED_LIB %s -fPIC -shared -o %t-so.so // RUN: %clangxx_asan -O3 %s %libdl -o %t && %run %t 2>&1 | FileCheck %s // XFAIL: i386-netbsd #if !defined(SHARED_LIB) #include #include #include #include #include #include #include #if defined(__FreeBSD__) // The MAP_NORESERVE define has been removed in FreeBSD 11.x, and even before // that, it was never implemented. So just define it to zero. #undef MAP_NORESERVE #define MAP_NORESERVE 0 #endif using std::string; typedef int *(fun_t)(); int main(int argc, char *argv[]) { string path = string(argv[0]) + "-so.so"; size_t PageSize = sysconf(_SC_PAGESIZE); printf("opening %s ... \n", path.c_str()); void *lib = dlopen(path.c_str(), RTLD_NOW); if (!lib) { printf("error in dlopen(): %s\n", dlerror()); return 1; } fun_t *get = (fun_t*)dlsym(lib, "get_address_of_static_var"); if (!get) { printf("failed dlsym\n"); return 1; } int *addr = get(); assert(((size_t)addr % 32) == 0); // should be 32-byte aligned. printf("addr: %p\n", addr); addr[0] = 1; // make sure we can write there. // Now dlclose the shared library. printf("attempting to dlclose\n"); if (dlclose(lib)) { printf("failed to dlclose\n"); return 1; } // Now, the page where 'addr' is unmapped. Map it. size_t page_beg = ((size_t)addr) & ~(PageSize - 1); void *res = mmap((void*)(page_beg), PageSize, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON | MAP_FIXED | MAP_NORESERVE, -1, 0); if (res == (char*)-1L) { printf("failed to mmap\n"); return 1; } addr[1] = 2; // BOOM (if the bug is not fixed). printf("PASS\n"); // CHECK: PASS return 0; } #else // SHARED_LIB #include static int pad1; static int static_var; static int pad2; extern "C" int *get_address_of_static_var() { return &static_var; } __attribute__((constructor)) void at_dlopen() { printf("%s: I am being dlopened\n", __FILE__); } __attribute__((destructor)) void at_dlclose() { printf("%s: I am being dlclosed\n", __FILE__); } #endif // SHARED_LIB