hfsplus: fix "unused node is not erased" error

Zero newly allocated extents in the catalog tree if volume attributes
tell us to.  Not doing so we risk getting the "unused node is not
erased" error.  See kHFSUnusedNodeFix flag in Apple's source code for
reference.

There was a previous commit clearing the node when it is freed: commit
899bed05e9f6 ("hfsplus: fix issue with unzeroed unused b-tree nodes").
But it did not handle newly allocated extents (this patch fixes it).
And it zeroed nodes in all trees unconditionally which is an overkill.

This patch adds a condition and also switches to 'tree->node_size' as a
simpler method of getting the length to zero.

Signed-off-by: Sergei Antonov <saproj@gmail.com>
Cc: Anton Altaparmakov <aia21@cam.ac.uk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Hin-Tak Leung <htl10@users.sourceforge.net>
Cc: Kyle Laracey <kalaracey@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/hfsplus/xattr.c b/fs/hfsplus/xattr.c
index c03c946..aab093c 100644
--- a/fs/hfsplus/xattr.c
+++ b/fs/hfsplus/xattr.c
@@ -196,7 +196,7 @@ check_attr_tree_state_again:
 	}
 
 	while (hip->alloc_blocks < hip->clump_blocks) {
-		err = hfsplus_file_extend(attr_file);
+		err = hfsplus_file_extend(attr_file, false);
 		if (unlikely(err)) {
 			pr_err("failed to extend attributes file\n");
 			goto end_attr_file_creation;