src/compiler-rt/test/asan/TestCases/Posix/dlclose-test.cc

   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 x86 Linux, but not necessary anywhere else.
  15 // REQUIRES: x86-target-arch
  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 #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 #if defined(__FreeBSD__)
  37 // The MAP_NORESERVE define has been removed in FreeBSD 11.x, and even before
  38 // that, it was never implemented. So just define it to zero.
  39 #undef MAP_NORESERVE
  40 #define MAP_NORESERVE 0
  41 #endif
  42
  43 using std::string;
  44
  45 typedef int *(fun_t)();
  46
  47 int main(int argc, char *argv[]) {
  48   string path = string(argv[0]) + "-so.so";
  49   size_t PageSize = sysconf(_SC_PAGESIZE);
  50   printf("opening %s ... \n", path.c_str());
  51   void *lib = dlopen(path.c_str(), RTLD_NOW);
  52   if (!lib) {
  53     printf("error in dlopen(): %s\n", dlerror());
  54     return 1;
  55   }
  56   fun_t *get = (fun_t*)dlsym(lib, "get_address_of_static_var");
  57   if (!get) {
  58     printf("failed dlsym\n");
  59     return 1;
  60   }
  61   int *addr = get();
  62   assert(((size_t)addr % 32) == 0);  // should be 32-byte aligned.
  63   printf("addr: %p\n", addr);
  64   addr[0] = 1;  // make sure we can write there.
  65
  66   // Now dlclose the shared library.
  67   printf("attempting to dlclose\n");
  68   if (dlclose(lib)) {
  69     printf("failed to dlclose\n");
  70     return 1;
  71   }
  72   // Now, the page where 'addr' is unmapped. Map it.
  73   size_t page_beg = ((size_t)addr) & ~(PageSize - 1);
  74   void *res = mmap((void*)(page_beg), PageSize,
  75                    PROT_READ | PROT_WRITE,
  76                    MAP_PRIVATE | MAP_ANON | MAP_FIXED | MAP_NORESERVE, -1, 0);
  77   if (res == (char*)-1L) {
  78     printf("failed to mmap\n");
  79     return 1;
  80   }
  81   addr[1] = 2;  // BOOM (if the bug is not fixed).
  82   printf("PASS\n");
  83   // CHECK: PASS
  84   return 0;
  85 }
  86 #else  // SHARED_LIB
  87 #include <stdio.h>
  88
  89 static int pad1;
  90 static int static_var;
  91 static int pad2;
  92
  93 extern "C"
  94 int *get_address_of_static_var() {
  95   return &static_var;
  96 }
  97
  98 __attribute__((constructor))
  99 void at_dlopen() {
 100   printf("%s: I am being dlopened\n", __FILE__);
 101 }
 102 __attribute__((destructor))
 103 void at_dlclose() {
 104   printf("%s: I am being dlclosed\n", __FILE__);
 105 }
 106 #endif  // SHARED_LIB