nptl/tst-setuid3.c

   1 /* Copyright (C) 2014-2018 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    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <stdio.h>
  19 #include <errno.h>
  20 #include <pthread.h>
  21 #include <stdbool.h>
  22 #include <unistd.h>
  23
  24 /* The test must run under a non-privileged user ID.  */
  25 static const uid_t test_uid = 1;
  26
  27 static pthread_barrier_t barrier1;
  28 static pthread_barrier_t barrier2;
  29
  30 #define FAIL(fmt, ...) \
  31   do { printf ("FAIL: " fmt "\n", __VA_ARGS__); _exit (1); } while (0)
  32
  33 #define FAIL_ERR(fmt, ...) \
  34   do { printf ("FAIL: " fmt ": %m\n", __VA_ARGS__); _exit (1); } while (0)
  35
  36 /* True if x is not a successful return code from pthread_barrier_wait.  */
  37 static inline bool
  38 is_invalid_barrier_ret (int x)
  39 {
  40   return x != 0 && x != PTHREAD_BARRIER_SERIAL_THREAD;
  41 }
  42
  43 static void *
  44 thread_func (void *ctx __attribute__ ((unused)))
  45 {
  46   int ret = pthread_barrier_wait (&barrier1);
  47   if (is_invalid_barrier_ret (ret))
  48     FAIL ("pthread_barrier_wait (barrier1) (on thread): %d", ret);
  49   ret = pthread_barrier_wait (&barrier2);
  50   if (is_invalid_barrier_ret (ret))
  51     FAIL ("pthread_barrier_wait (barrier2) (on thread): %d", ret);
  52   return NULL;
  53 }
  54
  55 static void
  56 setuid_failure (int phase)
  57 {
  58   int ret = setuid (0);
  59   switch (ret)
  60     {
  61     case 0:
  62       FAIL ("setuid succeeded unexpectedly in phase %d", phase);
  63     case -1:
  64       if (errno != EPERM)
  65         FAIL_ERR ("setuid phase %d", phase);
  66       break;
  67     default:
  68       FAIL ("invalid setuid return value in phase %d: %d", phase, ret);
  69     }
  70 }
  71
  72 static int
  73 do_test (void)
  74 {
  75   if (getuid () == 0)
  76     if (setuid (test_uid) != 0)
  77       FAIL_ERR ("setuid (%u)", (unsigned) test_uid);
  78   if (setuid (getuid ()))
  79     FAIL_ERR ("setuid (%s)", "getuid ()");
  80   setuid_failure (1);
  81
  82   int ret = pthread_barrier_init (&barrier1, NULL, 2);
  83   if (ret != 0)
  84     FAIL ("pthread_barrier_init (barrier1): %d", ret);
  85   ret = pthread_barrier_init (&barrier2, NULL, 2);
  86   if (ret != 0)
  87     FAIL ("pthread_barrier_init (barrier2): %d", ret);
  88
  89   pthread_t thread;
  90   ret = pthread_create (&thread, NULL, thread_func, NULL);
  91   if (ret != 0)
  92     FAIL ("pthread_create: %d", ret);
  93
  94   /* Ensure that the thread is running properly.  */
  95   ret = pthread_barrier_wait (&barrier1);
  96   if (is_invalid_barrier_ret (ret))
  97     FAIL ("pthread_barrier_wait (barrier1): %d", ret);
  98
  99   setuid_failure (2);
 100
 101   /* Check success case. */
 102   if (setuid (getuid ()) != 0)
 103     FAIL_ERR ("setuid (%s)", "getuid ()");
 104
 105   /* Shutdown.  */
 106   ret = pthread_barrier_wait (&barrier2);
 107   if (is_invalid_barrier_ret (ret))
 108     FAIL ("pthread_barrier_wait (barrier2): %d", ret);
 109
 110   ret = pthread_join (thread, NULL);
 111   if (ret != 0)
 112     FAIL ("pthread_join: %d", ret);
 113
 114   return 0;
 115 }
 116
 117 #define TEST_FUNCTION do_test ()
 118 #include "../test-skeleton.c"