elf/tst-dlmopen-dlerror.c

   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>