Re: install-sh misbehaves badly on buggy FreeBSD systems

[Paul Eggert]

Stepan Kasal <address@hidden> writes:

> is there an implementation of mkdir which understands `-p' and `--' but
> does not understand `-m'?

Not in the sense described here, no.  Ancient mkdir treats all
arguments as directories to be made, and `$mkdirprog $mkdir_mode -p --
"$tmpdir/d"' must fail because tmpdir does not exist.  I don't think
we need to worry about any mkdir understanding -p and -- but not -m;
even if there were an animal, it should treat -m as an unknown option
and should fail.

Your other ideas look good.  It's a bit more consistent to test
dir_arg rather than mkdir_mode (that's what the rest of the script
does).  So here's a revised patch.

2006-10-10  Paul Eggert  <address@hidden>

        * lib/install-sh (posix_mkdir): Reject FreeBSD 6.1 mkdir -p -m,
        which incorrectly sets the mode of an existing destination
        directory.  In some cases the unpatched install-sh could do the
        equivalent of "chmod 777 /" or "chmod 0 /" on a buggy FreeBSD
        system.  We hope this is rare in practice, but it's clearly worth
        fixing.  Problem reported by Alex in
        <http://lists.gnu.org/archive/html/bug-autoconf/2006-10/msg00012.html>.
        Also, don't bother to check for -m bugs unless we're using -m;
        suggested by Stepan Kasal.

--- lib/install-sh.~1.35.~      2006-07-09 09:09:31.000000000 -0700
+++ lib/install-sh      2006-10-10 12:05:29.000000000 -0700
@@ -336,12 +336,26 @@ do
            trap 'ret=$?; rmdir "$tmpdir/d" "$tmpdir" 2>/dev/null; exit $ret' 0
 
            if (umask $mkdir_umask &&
-               exec $mkdirprog $mkdir_mode -p -- / "$tmpdir/d") >/dev/null 2>&1
+               exec $mkdirprog $mkdir_mode -p -- "$tmpdir/d") >/dev/null 2>&1
            then
-             # Check for bugs in HP-UX 11.23 and IRIX 6.5 mkdir.
-             case `ls -ld "$tmpdir"` in
-               d????-??-* ) posix_mkdir=:;;
-             esac
+             if test -z "$dir_arg" || {
+                  # Check for POSIX incompatibilities with -m.
+                  # HP-UX 11.23 and IRIX 6.5 mkdir -m -p sets group- or
+                  # other-writeable bit of parent directory when it shouldn't.
+                  # FreeBSD 6.1 mkdir -m -p sets mode of existing directory.
+                  ls_ld_tmpdir=`ls -ld "$tmpdir"`
+                  case $ls_ld_tmpdir in
+                    d????-?r-*) different_mode=700;;
+                    d????-?--*) different_mode=755;;
+                    *) false;;
+                  esac &&
+                  $mkdirprog -m$different_mode -p -- "$tmpdir" && {
+                    ls_ld_tmpdir_1=`ls -ld "$tmpdir"`
+                    test "$ls_ld_tmpdir" = "$ls_ld_tmpdir_1"
+                  }
+                }
+             then posix_mkdir=:
+             fi
              rmdir "$tmpdir/d" "$tmpdir"
            else
              # Remove any dirs left behind by ancient mkdir implementations.