1  /* Check that dlfcn errors are reported properly after dlmopen.
       2     Copyright (C) 2021-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <http://www.gnu.org/licenses/>.  */
      18  
      19  #include <stddef.h>
      20  #include <string.h>
      21  #include <support/check.h>
      22  #include <support/xdlfcn.h>
      23  
      24  static int
      25  do_test (void)
      26  {
      27    void *handle = xdlmopen (LM_ID_NEWLM, "tst-dlmopen-dlerror-mod.so",
      28                             RTLD_NOW);
      29    void (*call_dlsym) (const char *name) = xdlsym (handle, "call_dlsym");
      30    void (*call_dlopen) (const char *name) = xdlsym (handle, "call_dlopen");
      31  
      32    /* Iterate over various name lengths.  This changes the size of
      33       error messages allocated by ld.so and has been shown to trigger
      34       detectable heap corruption if malloc/free calls in different
      35       namespaces are mixed.  */
      36    char buffer[2048];
      37    char *buffer_end = &buffer[sizeof (buffer) - 2];
      38    for (char *p = stpcpy (buffer, "does not exist "); p < buffer_end; ++p)
      39      {
      40        p[0] = 'X';
      41        p[1] = '\0';
      42        call_dlsym (buffer);
      43        call_dlopen (buffer);
      44      }
      45  
      46    return 0;
      47  }
      48  
      49  #include <support/test-driver.c>