gdb/testsuite/gdb.arch/amd64-invalid-stack-middle.c

   1 /* This testcase is part of GDB, the GNU debugger.
   2
   3    Copyright 2014-2019 Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program 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
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19 #include <sys/mman.h>
  20 #include <unistd.h>
  21 #include <assert.h>
  22
  23 void
  24 breakpt (void)
  25 {
  26   /* Nothing.  */
  27 }
  28
  29 void
  30 func5 (void)
  31 {
  32   breakpt ();
  33 }
  34
  35 void
  36 func4 (void)
  37 {
  38   func5 ();
  39 }
  40
  41 void
  42 func3 (void)
  43 {
  44   func4 ();
  45 }
  46
  47 void
  48 func2 (void *ptr)
  49 {
  50   func3 ();
  51 }
  52
  53 void
  54 func1 (void *ptr)
  55 {
  56   func2 (ptr);
  57 }
  58
  59 /* Finds and returns an invalid pointer, mmaps in a page, grabs a pointer
  60    to it then unmaps the page again.  This is almost certainly "undefined"
  61    behaviour, but should be good enough for this small test program.  */
  62
  63 static void *
  64 make_invalid_ptr (void)
  65 {
  66   int page_size, ans;
  67   void *ptr;
  68
  69   page_size = getpagesize ();
  70   ptr =  mmap (0, page_size, PROT_NONE,
  71                MAP_PRIVATE | MAP_ANONYMOUS,
  72                -1, 0);
  73   assert (ptr != MAP_FAILED);
  74   ans = munmap (ptr, page_size);
  75   assert (ans == 0);
  76
  77   return ptr;
  78 }
  79
  80 int
  81 main (void)
  82 {
  83   void *invalid_ptr;
  84
  85   invalid_ptr = make_invalid_ptr ();
  86   func1 (invalid_ptr);
  87
  88   return 0;
  89 }