From b982f17d9d036b7a0cac445c62983a30a0d16eb2 Mon Sep 17 00:00:00 2001
From: Eric Biggers <ebiggers3@gmail.com>
Date: Sat, 19 Sep 2015 11:31:06 -0500
Subject: [PATCH] Always specify AT_UNNAMED when opening unnamed stream with
 libntfs-3g

Using another empty string causes problems.
---
 src/ntfs-3g_apply.c   | 28 ++++++++++++++++++----------
 src/ntfs-3g_capture.c | 24 ++++++++++++++----------
 2 files changed, 32 insertions(+), 20 deletions(-)

diff --git a/src/ntfs-3g_apply.c b/src/ntfs-3g_apply.c
index 07dbdf65..148abc76 100644
--- a/src/ntfs-3g_apply.c
+++ b/src/ntfs-3g_apply.c
@@ -714,6 +714,7 @@ ntfs_3g_begin_extract_blob_instance(struct blob_descriptor *blob,
 				    struct ntfs_3g_apply_ctx *ctx)
 {
 	struct wim_dentry *one_dentry = inode_first_extraction_dentry(inode);
+	ntfschar *stream_name;
 	size_t stream_name_nchars;
 	ntfs_attr *attr;
 
@@ -736,22 +737,29 @@ ntfs_3g_begin_extract_blob_instance(struct blob_descriptor *blob,
 	/* It's a data stream (may be unnamed or named).  */
 	wimlib_assert(strm->stream_type == STREAM_TYPE_DATA);
 
-	stream_name_nchars = utf16le_len_chars(strm->stream_name);
+	if (unlikely(stream_is_named(strm))) {
+		stream_name = strm->stream_name;
+		stream_name_nchars = utf16le_len_chars(stream_name);
 
-	if (stream_name_nchars &&
-	    (ntfs_attr_add(ni, AT_DATA, strm->stream_name,
-			   stream_name_nchars, NULL, 0)))
-	{
-		ERROR_WITH_ERRNO("Failed to create named data stream of \"%s\"",
-				 dentry_full_path(one_dentry));
-		return WIMLIB_ERR_NTFS_3G;
+		if (ntfs_attr_add(ni, AT_DATA, stream_name,
+				  stream_name_nchars, NULL, 0))
+		{
+			ERROR_WITH_ERRNO("Failed to create named data stream of \"%s\"",
+					 dentry_full_path(one_dentry));
+			return WIMLIB_ERR_NTFS_3G;
+		}
+	} else {
+		/* Don't pass an empty string other than AT_UNNAMED to
+		 * ntfs_attr_open() --- it violates assumptions made by
+		 * libntfs-3g.  */
+		stream_name = AT_UNNAMED;
+		stream_name_nchars = 0;
 	}
 
 	/* This should be ensured by extract_blob_list()  */
 	wimlib_assert(ctx->num_open_attrs < MAX_OPEN_FILES);
 
-	attr = ntfs_attr_open(ni, AT_DATA, strm->stream_name,
-			      stream_name_nchars);
+	attr = ntfs_attr_open(ni, AT_DATA, stream_name, stream_name_nchars);
 	if (!attr) {
 		ERROR_WITH_ERRNO("Failed to open data stream of \"%s\"",
 				 dentry_full_path(one_dentry));
diff --git a/src/ntfs-3g_capture.c b/src/ntfs-3g_capture.c
index fe1fbf55..d9a7f2f6 100644
--- a/src/ntfs-3g_capture.c
+++ b/src/ntfs-3g_capture.c
@@ -70,7 +70,7 @@ struct ntfs_location {
 	u64 mft_no;
 	ATTR_TYPES attr_type;
 	u32 attr_name_nchars;
-	utf16lechar *attr_name;
+	ntfschar *attr_name;
 	u64 sort_key;
 };
 
@@ -167,7 +167,8 @@ void
 free_ntfs_location(struct ntfs_location *loc)
 {
 	put_ntfs_volume(loc->volume);
-	FREE(loc->attr_name);
+	if (loc->attr_name != AT_UNNAMED)
+		FREE(loc->attr_name);
 	FREE(loc);
 }
 
@@ -177,7 +178,7 @@ clone_ntfs_location(const struct ntfs_location *loc)
 	struct ntfs_location *new = memdup(loc, sizeof(*loc));
 	if (!new)
 		goto err0;
-	if (loc->attr_name) {
+	if (loc->attr_name != AT_UNNAMED) {
 		new->attr_name = utf16le_dup(loc->attr_name);
 		if (!new->attr_name)
 			goto err1;
@@ -316,7 +317,7 @@ scan_ntfs_attr(struct wim_inode *inode,
 	u64 data_size = ntfs_get_attribute_value_length(record);
 	const u32 name_nchars = record->name_length;
 	struct blob_descriptor *blob = NULL;
-	utf16lechar *stream_name = NULL;
+	utf16lechar *stream_name = (utf16lechar *)NO_STREAM_NAME;
 	int ret;
 
 	if (unlikely(name_nchars)) {
@@ -354,7 +355,7 @@ scan_ntfs_attr(struct wim_inode *inode,
 			goto out_cleanup;
 		}
 
-		blob->ntfs_loc = CALLOC(1, sizeof(struct ntfs_location));
+		blob->ntfs_loc = MALLOC(sizeof(struct ntfs_location));
 		if (unlikely(!blob->ntfs_loc)) {
 			ret = WIMLIB_ERR_NOMEM;
 			goto out_cleanup;
@@ -363,16 +364,19 @@ scan_ntfs_attr(struct wim_inode *inode,
 		blob->blob_location = BLOB_IN_NTFS_VOLUME;
 		blob->size = data_size;
 		blob->ntfs_loc->volume = get_ntfs_volume(volume);
-		blob->ntfs_loc->attr_type = type;
 		blob->ntfs_loc->mft_no = ni->mft_no;
+		blob->ntfs_loc->attr_type = type;
 
 		if (unlikely(name_nchars)) {
+			blob->ntfs_loc->attr_name_nchars = name_nchars;
 			blob->ntfs_loc->attr_name = utf16le_dup(stream_name);
 			if (!blob->ntfs_loc->attr_name) {
 				ret = WIMLIB_ERR_NOMEM;
 				goto out_cleanup;
 			}
-			blob->ntfs_loc->attr_name_nchars = name_nchars;
+		} else {
+			blob->ntfs_loc->attr_name_nchars = 0;
+			blob->ntfs_loc->attr_name = AT_UNNAMED;
 		}
 
 		ret = set_attr_sort_key(ni, blob->ntfs_loc);
@@ -381,11 +385,11 @@ scan_ntfs_attr(struct wim_inode *inode,
 	}
 
 	ret = add_stream(inode, path, attr_type_to_wimlib_stream_type(type),
-			 stream_name ? stream_name : NO_STREAM_NAME,
-			 &blob, unhashed_blobs);
+			 stream_name, &blob, unhashed_blobs);
 out_cleanup:
 	free_blob_descriptor(blob);
-	FREE(stream_name);
+	if (stream_name != NO_STREAM_NAME)
+		FREE(stream_name);
 	return ret;
 }
 
-- 
2.43.0