rm -rf unremovable-non-dir gives no diagnostic [Re: not a directory mis-error

[Jim Meyering]

address@hidden (Karl Berry) wrote:
> Hi Jim,
>
> With coreutils 6.7, try (as a regular user) something like:
>   mv /etc/issue ~
>
> where /etc/issue is owned by root and not writable to the user:
> -rw-r--r-- 1 root root 76 Jul 18 18:51 /etc/issue
>
> *and* the destination is on a different filesystem.  I get:
> mv: cannot remove `/etc/issue': Not a directory
>
> I'd expect "Permission denied".  It's true enough that /etc/issue is not
> a directory, but I don't see the relevance :).  Probably I'm being dense
> as usual ...
>
> I do get permission denied when the target dir is on the same file system:
> \mv /etc/issue /tmp
> mv: cannot move `/etc/issue' to `/tmp/issue': Permission denied
>
> $ df /etc /tmp ~
> Filesystem         1048576-blocks      Used Available Capacity Mounted on
> /dev/hda5                   9845M     6936M     2409M      75% /
> /dev/hda5                   9845M     6936M     2409M      75% /
> /dev/sda4                  93896M    21974M    67152M      25% /u
>
> This is on my Red Hat WS4.1 system, Linux 2.6.9-42.0.3.EL.

Hi Karl,

Thank you for the report.
Actually, as the subject says, the underlying problem is slightly worse :-)
Here's the patch I've just checked in.

---
 ChangeLog            |   12 +++++++++++
 NEWS                 |    7 ++++++
 src/remove.c         |    4 +-
 tests/rm/Makefile.am |    1 +
 tests/rm/fail-eacces |   53 ++++++++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 75 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index ded5770..67aff09 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,17 @@
 2006-12-20  Jim Meyering  <address@hidden>

+       "rm -rf /etc/motd" (run by non-root) now prints a diagnostic.
+       * src/remove.c (remove_entry): Handle EACCES for a non-directory, too.
+       Don't let a non-directory get by with errno == EPERM, either.
+       Check the file type directly (using cached stat value), rather
+       than trying to guess it from errno values.
+       Karl Berry reported that a cross-partition "mv /etc/issue ~"
+       failed with the um,... suboptimal diagnostic,
+       "mv: cannot remove `/etc/issue': Not a directory".
+       * tests/rm/Makefile.am (TESTS): Add fail-eacces.
+       * tests/rm/fail-eacces: New file.
+       * NEWS: Mention that both mv and rm are affected.
+
        "cut -f 2- A B" no longer triggers a double-free bug
        * src/cut.c (cut_fields): Set file-scoped global to NULL after
        freeing it.  This avoids a double-free (and core dump on some systems)
diff --git a/NEWS b/NEWS
index d4e73a8..bf1d287 100644
--- a/NEWS
+++ b/NEWS
@@ -14,6 +14,13 @@ GNU coreutils NEWS                                    -*- 
outline -*-
   more file arguments.  This was due to a double-free bug, introduced
   in coreutils-5.3.0.

+  A cross-partition "mv /etc/passwd ~" (by non-root) now prints
+  a reasonable diagnostic.  Before, it would print this:
+  "mv: cannot remove `/etc/passwd': Not a directory".
+
+  "rm -rf /etc/passwd" (run by non-root) now prints a diagnostic.
+  Before it would print nothing.
+
 * Noteworthy changes in release 6.7 (2006-12-08) [stable]

 ** Bug fixes
diff --git a/src/remove.c b/src/remove.c
index 3dc6929..f6d3f0c 100644
--- a/src/remove.c
+++ b/src/remove.c
@@ -1016,8 +1016,7 @@ remove_entry (int fd_cwd, Dirstack_state const *ds, char 
const *filename,
        errno = EISDIR;

       if (! x->recursive
-         || errno == ENOENT || errno == ENOTDIR
-         || errno == ELOOP || errno == ENAMETOOLONG)
+         || (cache_stat_ok (st) && !S_ISDIR (st->st_mode)))
        {
          if (ignorable_missing (x, errno))
            return RM_OK;
@@ -1028,6 +1027,7 @@ remove_entry (int fd_cwd, Dirstack_state const *ds, char 
const *filename,
                 quote (full_filename (filename)));
          return RM_ERROR;
        }
+      assert (!cache_stat_ok (st) || S_ISDIR (st->st_mode));
     }
   else
     {
diff --git a/tests/rm/Makefile.am b/tests/rm/Makefile.am
index 6670307..f632100 100644
--- a/tests/rm/Makefile.am
+++ b/tests/rm/Makefile.am
@@ -21,6 +21,7 @@
 AUTOMAKE_OPTIONS = 1.1 gnits

 TESTS = \
+  fail-eacces \
   one-file-system \
   ignorable \
   readdir-bug \
diff --git a/tests/rm/fail-eacces b/tests/rm/fail-eacces
new file mode 100755
index 0000000..29bc911
--- /dev/null
+++ b/tests/rm/fail-eacces
@@ -0,0 +1,53 @@
+#!/bin/sh
+# Ensure that rm -rf unremovable-non-dir gives a diagnostic.
+
+# Copyright (C) 2006 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+# 02110-1301, USA.
+
+if test "$VERBOSE" = yes; then
+  set -x
+  rm --version
+fi
+
+. $srcdir/../lang-default
+
+pwd=`pwd`
+t0=`echo "$0"|sed 's,.*/,,'`.tmp; tmp=$t0/$$
+trap 'status=$?; cd "$pwd" && chmod -R u+rwx $t0 && rm -rf $t0 && exit 
$status' 0
+trap '(exit $?); exit $?' 1 2 13 15
+
+framework_failure=0
+mkdir -p $tmp || framework_failure=1
+cd $tmp || framework_failure=1
+mkdir d && touch d/f && chmod a-w d || framework_failure=1
+
+if test $framework_failure = 1; then
+  echo "$0: failure in testing framework" 1>&2
+  (exit 1); exit 1
+fi
+
+fail=0
+
+rm -rf d/f 2> out && fail=1
+cat <<\EOF > exp
+rm: cannot remove `d/f': Permission denied
+EOF
+
+cmp out exp || fail=1
+test $fail = 1 && diff out exp 2> /dev/null
+
+(exit $fail); exit $fail
--
1.4.4.3.g5485