acl: Fix WALK_TREE_RECURSIVE for the WALK_TREE_DEREFERENCE case

NOTE: Sending to [email protected] instead of acl-devel since it doesn't seem active anymore.

getfacl.c calls walk_tree() with WALK_TREE_DEREFERENCE. This causes a stat() of symlinks which in turn causes S_ISDIR(st.st_mode) to be true on symlinks.

This causes getfacl -P to return the contents of symlinks...

e.g.

$ mkdir -p test/sub
$ mkdir test/link
$ touch test/link/file
$ ln -s `pwd`/test/link test/sub/link
$ getfacl -P -R test/sub

# file: test/sub
# owner: philips
# group: users
user::rwx
group::r-x
other::r-x

# file: test/sub/link/file
# owner: philips
# group: users
user::rw-
group::r--
other::r--

After the fix:

$ getfacl -R -P test/sub/
# file: test/sub/
# owner: philips
# group: users
user::rwx
group::r-x
other::r-x

---
 libmisc/walk_tree.c |    9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

Index: acl-2.2.47/libmisc/walk_tree.c
===================================================================
@@ -93,8 +93,15 @@ static int walk_tree_rec(const char *pat
 		have_dir_stat = 1;
 	}
 	err = func(path, &st, flags, arg);
+
+	/*
+	 * Recurse if WALK_TREE_RECURSIVE and the path is:
+	 * 	a dir not from a symlink
+	 * 	a link and follow_symlinks
+	 */
 	if ((flags & WALK_TREE_RECURSIVE) &&
-	    (S_ISDIR(st.st_mode) || (S_ISLNK(st.st_mode) && follow_symlinks))) {
+	    (!(flags & WALK_TREE_SYMLINK) && S_ISDIR(st.st_mode)) ||
+	    ((flags & WALK_TREE_SYMLINK) && follow_symlinks)) {
 		struct dirent *entry;
 
 		/*