tests/rm/rm-readdir-fail.sh

   1 #!/bin/sh
   2 # Test rm's behavior when the directory cannot be read.
   3 # This test is skipped on systems that lack LD_PRELOAD support.
   4
   5 # Copyright (C) 2016-2024 Free Software Foundation, Inc.
   6
   7 # This program is free software: you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation, either version 3 of the License, or
  10 # (at your option) any later version.
  11
  12 # This program is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU General Public License for more details.
  16
  17 # You should have received a copy of the GNU General Public License
  18 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
  19
  20 . "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
  21 print_ver_ rm
  22 require_gcc_shared_
  23
  24 mkdir -p dir/notempty || framework_failure_
  25
  26 # Simulate "readdir" failure.
  27 cat > k.c <<\EOF || framework_failure_
  28 #define _GNU_SOURCE
  29
  30 /* Setup so we don't have to worry about readdir64.  */
  31 #ifndef __LP64__
  32 # define _FILE_OFFSET_BITS 64
  33 #endif
  34
  35 #include <dlfcn.h>
  36 #include <dirent.h>
  37 #include <errno.h>
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40
  41 struct dirent *readdir (DIR *dirp)
  42 {
  43   static int count = 1;
  44
  45 #ifndef __LP64__
  46   if (count == 1)
  47     fclose (fopen ("32bit", "w"));
  48   errno = ENOSYS;
  49   return NULL;
  50 #endif
  51
  52   static struct dirent *(*real_readdir)(DIR *dirp);
  53   if (! real_readdir && ! (real_readdir = dlsym (RTLD_NEXT, "readdir")))
  54     {
  55       fprintf (stderr, "Failed to find readdir()\n");
  56       errno = ESRCH;
  57       return NULL;
  58     }
  59   struct dirent* d;
  60   if (! (d = real_readdir (dirp)))
  61     {
  62       fprintf (stderr, "Failed to get dirent\n");
  63       errno = ENOENT;
  64       return NULL;
  65     }
  66
  67   /* Flag that LD_PRELOAD and above functions work.  */
  68   if (count == 1)
  69     fclose (fopen ("preloaded", "w"));
  70
  71   /* Return some entries to trigger partial read failure,
  72      ensuring we don't return ignored '.' or '..'  */
  73   char const *readdir_partial = getenv ("READDIR_PARTIAL");
  74   if (readdir_partial && *readdir_partial && count <= 3)
  75     {
  76       count++;
  77       d->d_name[0]='0'+count; d->d_name[1]='\0';
  78 #ifdef _DIRENT_HAVE_D_NAMLEN
  79       d->d_namlen = 1;
  80 #endif
  81       errno = 0;
  82       return d;
  83     };
  84
  85   /* Fail.  */
  86   errno = ENOENT;
  87   return NULL;
  88 }
  89 EOF
  90
  91 # Then compile/link it:
  92 gcc_shared_ k.c k.so \
  93   || framework_failure_ 'failed to build shared library'
  94
  95 # Test if LD_PRELOAD works:
  96 export READDIR_PARTIAL
  97 for READDIR_PARTIAL in '' '1'; do
  98   rm -f preloaded
  99   (export LD_PRELOAD=$LD_PRELOAD:./k.so
 100    returns_ 1 rm -Rf dir 2>>errt) || fail=1
 101   if test -f 32bit; then
 102     skip_ 'This test only supports 64 bit systems'
 103   elif ! test -f preloaded; then
 104     cat errt
 105     skip_ "internal test failure: maybe LD_PRELOAD doesn't work?"
 106   fi
 107 done
 108
 109 # First case is failure to read any items from dir, then assume empty.
 110 # Generally that will be diagnosed when rm tries to rmdir().
 111 # Second case is more general error where we fail immediately
 112 # (with ENOENT in this case but it could be anything).
 113 cat <<EOF > exp
 114 rm: cannot remove 'dir'
 115 Failed to get dirent
 116 rm: traversal failed: dir
 117 EOF
 118 sed 's/\(rm:.*\):.*/\1/' errt > err || framework_failure_
 119 compare exp err || fail=1
 120
 121 Exit $fail