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 36using std::string; 37 38typedef int *(fun_t)(); 39 40int 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 82static int pad1; 83static int static_var; 84static int pad2; 85 86extern "C" 87int *get_address_of_static_var() { 88 return &static_var; 89} 90 91__attribute__((constructor)) 92void at_dlopen() { 93 printf("%s: I am being dlopened\n", __FILE__); 94} 95__attribute__((destructor)) 96void at_dlclose() { 97 printf("%s: I am being dlclosed\n", __FILE__); 98} 99#endif // SHARED_LIB 100