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      <base href="https://llvm.org/bugs/" />
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    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW --- - asan/TestCases/strtol_strict.c is sensitive to heap content"
   href="https://llvm.org/bugs/show_bug.cgi?id=23230">23230</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>asan/TestCases/strtol_strict.c is sensitive to heap content
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>compiler-rt
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>unspecified
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>PC
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Linux
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>compiler-rt
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>unassignedbugs@nondot.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>hjl.tools@gmail.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvmbugs@cs.uiuc.edu
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr></table>
      <p>
        <div>
        <pre>asan/TestCases/strtol_strict.c has

void test3(char *array, char *endptr) {
  // Buffer overflow if base is invalid.
  long r = strtol(array - 1, NULL, -1);
  assert(r == 0); 
}
...

int main(int argc, char **argv) {
  char *array = (char*)malloc(3);
  char *endptr = NULL;
  array[0] = '1';
  array[1] = '2';
  array[2] = '3';
...
  if (!strcmp(argv[1], "test3")) test3(array, endptr);
  // CHECK3: {{.*ERROR: AddressSanitizer: heap-buffer-overflow on address}}
  // CHECK3: READ of size 5

When array[-1] happens to be '\0', we will get

READ of size 1 at 0x60200000efef thread T0

instead of

READ of size 5 at 0x60200000efef thread T0</pre>
        </div>
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