compiler-rt/test/msan/Linux/process_vm_readv.cpp

   1 // RUN: %clangxx_msan -std=c++11 -O0 %s -o %t && %run %t
   2 // RUN: %clangxx_msan -std=c++11 -O0 %s -o %t -DPOSITIVE && not %run %t 2>&1 | FileCheck %s
   3
   4 #include <assert.h>
   5 #include <dlfcn.h>
   6 #include <sanitizer/msan_interface.h>
   7 #include <stdio.h>
   8 #include <string.h>
   9 #include <sys/types.h>
  10 #include <sys/uio.h>
  11 #include <unistd.h>
  12 #include <errno.h>
  13
  14 typedef ssize_t (*process_vm_readwritev_fn)(pid_t, const iovec *, unsigned long,
  15                                             const iovec *, unsigned long,
  16                                             unsigned long);
  17
  18 // Exit with success, emulating the expected output.
  19 int exit_dummy()
  20 {
  21 #ifdef POSITIVE
  22     printf("process_vm_readv not found or not implemented!\n");
  23     printf(
  24         "WARNING: MemorySanitizer: use-of-uninitialized-value (not really)\n");
  25     return 1;
  26 #else
  27     return 0;
  28 #endif
  29 }
  30
  31 int main(void) {
  32   // This requires glibc 2.15.
  33   process_vm_readwritev_fn libc_process_vm_readv =
  34       (process_vm_readwritev_fn)dlsym(RTLD_NEXT, "process_vm_readv");
  35   if (!libc_process_vm_readv)
  36     return exit_dummy();
  37
  38   process_vm_readwritev_fn process_vm_readv =
  39       (process_vm_readwritev_fn)dlsym(RTLD_DEFAULT, "process_vm_readv");
  40   process_vm_readwritev_fn process_vm_writev =
  41       (process_vm_readwritev_fn)dlsym(RTLD_DEFAULT, "process_vm_writev");
  42
  43   char a[100];
  44   memset(a, 0xab, 100);
  45
  46   char b[100];
  47   iovec iov_a[] = {{(void *)a, 20}, (void *)(a + 50), 10};
  48   iovec iov_b[] = {{(void *)(b + 10), 10}, (void *)(b + 30), 20};
  49
  50   __msan_poison(&b, sizeof(b));
  51   ssize_t res = process_vm_readv(getpid(), iov_b, 2, iov_a, 2, 0);
  52   if (errno == ENOSYS) // Function not implemented
  53     return exit_dummy();
  54
  55   assert(res == 30);
  56   __msan_check_mem_is_initialized(b + 10, 10);
  57   __msan_check_mem_is_initialized(b + 30, 20);
  58   assert(__msan_test_shadow(b + 9, 1) == 0);
  59   assert(__msan_test_shadow(b + 20, 1) == 0);
  60   assert(__msan_test_shadow(b + 29, 1) == 0);
  61   assert(__msan_test_shadow(b + 50, 1) == 0);
  62
  63 #ifdef POSITIVE
  64   __msan_unpoison(&b, sizeof(b));
  65   __msan_poison(b + 32, 1);
  66   res = process_vm_writev(getpid(), iov_b, 2, iov_a, 2, 0);
  67 // CHECK: WARNING: MemorySanitizer: use-of-uninitialized-value
  68 #else
  69   __msan_unpoison(&b, sizeof(b));
  70   res = process_vm_writev(getpid(), iov_b, 2, iov_a, 2, 0);
  71   assert(res == 30);
  72 #endif
  73
  74   return 0;
  75 }