elf/tst-env-setuid.c

   1 /* Copyright (C) 2012-2023 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 /* Verify that tunables correctly filter out unsafe environment variables like
  19    MALLOC_CHECK_ and MALLOC_MMAP_THRESHOLD_ but also retain
  20    MALLOC_MMAP_THRESHOLD_ in an unprivileged child.  */
  21
  22 #include <errno.h>
  23 #include <fcntl.h>
  24 #include <stdlib.h>
  25 #include <stdint.h>
  26 #include <stdio.h>
  27 #include <string.h>
  28 #include <sys/stat.h>
  29 #include <sys/wait.h>
  30 #include <unistd.h>
  31
  32 #include <support/check.h>
  33 #include <support/support.h>
  34 #include <support/test-driver.h>
  35 #include <support/capture_subprocess.h>
  36
  37 static char SETGID_CHILD[] = "setgid-child";
  38
  39 #ifndef test_child
  40 static int
  41 test_child (void)
  42 {
  43   if (getenv ("MALLOC_CHECK_") != NULL)
  44     {
  45       printf ("MALLOC_CHECK_ is still set\n");
  46       return 1;
  47     }
  48
  49   if (getenv ("MALLOC_MMAP_THRESHOLD_") == NULL)
  50     {
  51       printf ("MALLOC_MMAP_THRESHOLD_ lost\n");
  52       return 1;
  53     }
  54
  55   if (getenv ("LD_HWCAP_MASK") != NULL)
  56     {
  57       printf ("LD_HWCAP_MASK still set\n");
  58       return 1;
  59     }
  60
  61   return 0;
  62 }
  63 #endif
  64
  65 #ifndef test_parent
  66 static int
  67 test_parent (void)
  68 {
  69   if (getenv ("MALLOC_CHECK_") == NULL)
  70     {
  71       printf ("MALLOC_CHECK_ lost\n");
  72       return 1;
  73     }
  74
  75   if (getenv ("MALLOC_MMAP_THRESHOLD_") == NULL)
  76     {
  77       printf ("MALLOC_MMAP_THRESHOLD_ lost\n");
  78       return 1;
  79     }
  80
  81   if (getenv ("LD_HWCAP_MASK") == NULL)
  82     {
  83       printf ("LD_HWCAP_MASK lost\n");
  84       return 1;
  85     }
  86
  87   return 0;
  88 }
  89 #endif
  90
  91 static int
  92 do_test (int argc, char **argv)
  93 {
  94   /* Setgid child process.  */
  95   if (argc == 2 && strcmp (argv[1], SETGID_CHILD) == 0)
  96     {
  97       if (getgid () == getegid ())
  98         /* This can happen if the file system is mounted nosuid.  */
  99         FAIL_UNSUPPORTED ("SGID failed: GID and EGID match (%jd)\n",
 100                           (intmax_t) getgid ());
 101
 102       int ret = test_child ();
 103
 104       if (ret != 0)
 105         exit (1);
 106
 107       exit (EXIT_SUCCESS);
 108     }
 109   else
 110     {
 111       if (test_parent () != 0)
 112         exit (1);
 113
 114       int status = support_capture_subprogram_self_sgid (SETGID_CHILD);
 115
 116       if (WEXITSTATUS (status) == EXIT_UNSUPPORTED)
 117         return EXIT_UNSUPPORTED;
 118
 119       if (!WIFEXITED (status))
 120         FAIL_EXIT1 ("Unexpected exit status %d from child process\n", status);
 121
 122       return 0;
 123     }
 124 }
 125
 126 #define TEST_FUNCTION_ARGV do_test
 127 #include <support/test-driver.c>