nss/tst-nss-db-endpwent.c

   1 /* Test for endpwent->getpwent crash for BZ #24695
   2    Copyright (C) 2019-2024 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    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <stdlib.h>
  20 #include <string.h>
  21 #include <sys/types.h>
  22 #include <pwd.h>
  23
  24 #include <support/support.h>
  25 #include <support/check.h>
  26 #include <support/xstdlib.h>
  27
  28 /* It is entirely allowed to start with a getpwent call without
  29    resetting the state of the service via a call to setpwent.
  30    You can also call getpwent more times than you have entries in
  31    the service, and it should not fail.  This test iteratates the
  32    database once, gets to the end, and then attempts a second
  33    iteration to look for crashes.  */
  34
  35 static void
  36 try_it (void)
  37 {
  38   struct passwd *pw;
  39
  40   /* setpwent is intentionally omitted here.  The first call to
  41      getpwent detects that it's first and initializes.  The second
  42      time try_it is called, this "first call" was not detected before
  43      the fix, and getpwent would crash.  */
  44
  45   while ((pw = getpwent ()) != NULL)
  46     ;
  47
  48   /* We only care if this segfaults or not.  */
  49   endpwent ();
  50 }
  51
  52 static int
  53 do_test (void)
  54 {
  55   char *cmd;
  56
  57   cmd = xasprintf ("%s/makedb -o /var/db/passwd.db /var/db/passwd.in",
  58                    support_bindir_prefix);
  59   xsystem (cmd);
  60   free (cmd);
  61
  62   try_it ();
  63   try_it ();
  64
  65   return 0;
  66 }
  67 #include <support/test-driver.c>