X-Git-Url: https://git.sven.stormbind.net/?p=sven%2Fexfat-utils.git;a=blobdiff_plain;f=libexfat%2Fnode.c;h=f3d10e0ef8d05cc1a6be8c162f919b73e1071011;hp=4cbb3e2d6d06f976d9e1097726662cb8a3e1056e;hb=8901366d256057ea67f6ceecc4686204fbe1b34f;hpb=4c15e072cf41b39ffa0c4354c64856a9c8414edf

diff --git a/libexfat/node.c b/libexfat/node.c
index 4cbb3e2..f3d10e0 100644
--- a/libexfat/node.c
+++ b/libexfat/node.c
@@ -2,11 +2,12 @@
 	node.c (09.10.09)
 	exFAT file system implementation library.
 
-	Copyright (C) 2010-2012  Andrew Nayenko
+	Free exFAT implementation.
+	Copyright (C) 2010-2015  Andrew Nayenko
 
-	This program is free software: you can redistribute it and/or modify
+	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 3 of the License, or
+	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,
@@ -14,8 +15,9 @@
 	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, see <http://www.gnu.org/licenses/>.
+	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.
 */
 
 #include "exfat.h"
@@ -42,28 +44,46 @@ struct exfat_node* exfat_get_node(struct exfat_node* node)
 
 void exfat_put_node(struct exfat* ef, struct exfat_node* node)
 {
-	if (--node->references < 0)
+	char buffer[UTF8_BYTES(EXFAT_NAME_MAX) + 1];
+
+	--node->references;
+	if (node->references < 0)
 	{
-		char buffer[EXFAT_NAME_MAX + 1];
-		exfat_get_name(node, buffer, EXFAT_NAME_MAX);
-		exfat_bug("reference counter of `%s' is below zero", buffer);
+		exfat_get_name(node, buffer, sizeof(buffer) - 1);
+		exfat_bug("reference counter of '%s' is below zero", buffer);
 	}
-
-	if (node->references == 0)
+	else if (node->references == 0 && node != ef->root)
 	{
 		if (node->flags & EXFAT_ATTRIB_DIRTY)
-			exfat_flush_node(ef, node);
-		if (node->flags & EXFAT_ATTRIB_UNLINKED)
 		{
-			/* free all clusters and node structure itself */
-			exfat_truncate(ef, node, 0);
-			free(node);
+			exfat_get_name(node, buffer, sizeof(buffer) - 1);
+			exfat_warn("dirty node '%s' with zero references", buffer);
 		}
-		if (ef->cmap.dirty)
-			exfat_flush_cmap(ef);
 	}
 }
 
+/**
+ * This function must be called on rmdir and unlink (after the last
+ * exfat_put_node()) to free clusters.
+ */
+int exfat_cleanup_node(struct exfat* ef, struct exfat_node* node)
+{
+	int rc = 0;
+
+	if (node->references != 0)
+		exfat_bug("unable to cleanup a node with %d references",
+				node->references);
+
+	if (node->flags & EXFAT_ATTRIB_UNLINKED)
+	{
+		/* free all clusters and node structure itself */
+		rc = exfat_truncate(ef, node, 0, true);
+		/* free the node even in case of error or its memory will be lost */
+		free(node);
+	}
+	return rc;
+}
+
 /**
  * Cluster + offset from the beginning of the directory to absolute offset.
  */
@@ -86,8 +106,12 @@ static int opendir(struct exfat* ef, const struct exfat_node* dir,
 		exfat_error("out of memory");
 		return -ENOMEM;
 	}
-	exfat_pread(ef->dev, it->chunk, CLUSTER_SIZE(*ef->sb),
-			exfat_c2o(ef, it->cluster));
+	if (exfat_pread(ef->dev, it->chunk, CLUSTER_SIZE(*ef->sb),
+			exfat_c2o(ef, it->cluster)) < 0)
+	{
+		exfat_error("failed to read directory cluster %#x", it->cluster);
+		return -EIO;
+	}
 	return 0;
 }
 
@@ -100,7 +124,7 @@ static void closedir(struct iterator* it)
 	it->chunk = NULL;
 }
 
-static int fetch_next_entry(struct exfat* ef, const struct exfat_node* parent,
+static bool fetch_next_entry(struct exfat* ef, const struct exfat_node* parent,
 		struct iterator* it)
 {
 	/* move iterator to the next entry in the directory */
@@ -111,17 +135,23 @@ static int fetch_next_entry(struct exfat* ef, const struct exfat_node* parent,
 		/* reached the end of directory; the caller should check this
 		   condition too */
 		if (it->offset >= parent->size)
-			return 0;
+			return true;
 		it->cluster = exfat_next_cluster(ef, parent, it->cluster);
 		if (CLUSTER_INVALID(it->cluster))
 		{
-			exfat_error("invalid cluster while reading directory");
-			return 1;
+			exfat_error("invalid cluster 0x%x while reading directory",
+					it->cluster);
+			return false;
+		}
+		if (exfat_pread(ef->dev, it->chunk, CLUSTER_SIZE(*ef->sb),
+				exfat_c2o(ef, it->cluster)) < 0)
+		{
+			exfat_error("failed to read the next directory cluster %#x",
+					it->cluster);
+			return false;
 		}
-		exfat_pread(ef->dev, it->chunk, CLUSTER_SIZE(*ef->sb),
-				exfat_c2o(ef, it->cluster));
 	}
-	return 0;
+	return true;
 }
 
 static struct exfat_node* allocate_node(void)
@@ -163,6 +193,40 @@ static const struct exfat_entry* get_entry_ptr(const struct exfat* ef,
 			(it->chunk + it->offset % CLUSTER_SIZE(*ef->sb));
 }
 
+static bool check_node(const struct exfat_node* node, uint16_t actual_checksum,
+		uint16_t reference_checksum, uint64_t valid_size)
+{
+	char buffer[UTF8_BYTES(EXFAT_NAME_MAX) + 1];
+
+	/*
+	   Validate checksum first. If it's invalid all other fields probably
+	   contain just garbage.
+	*/
+	if (actual_checksum != reference_checksum)
+	{
+		exfat_get_name(node, buffer, sizeof(buffer) - 1);
+		exfat_error("'%s' has invalid checksum (%#hx != %#hx)", buffer,
+				actual_checksum, reference_checksum);
+		return false;
+	}
+
+	/*
+	   exFAT does not support sparse files but allows files with uninitialized
+	   clusters. For such files valid_size means initialized data size and
+	   cannot be greater than file size. See SetFileValidData() function
+	   description in MSDN.
+	*/
+	if (valid_size > node->size)
+	{
+		exfat_get_name(node, buffer, sizeof(buffer) - 1);
+		exfat_error("'%s' has valid size (%"PRIu64") greater than size "
+				"(%"PRIu64")", buffer, valid_size, node->size);
+		return false;
+	}
+
+	return true;
+}
+
 /*
  * Reads one entry in directory at position pointed by iterator and fills
  * node structure.
@@ -182,6 +246,7 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
 	le16_t* namep = NULL;
 	uint16_t reference_checksum = 0;
 	uint16_t actual_checksum = 0;
+	uint64_t valid_size = 0;
 
 	*node = NULL;
 
@@ -216,6 +281,12 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
 				exfat_error("too few continuations (%hhu)", continuations);
 				goto error;
 			}
+			if (continuations > 1 +
+					DIV_ROUND_UP(EXFAT_NAME_MAX, EXFAT_ENAME_MAX))
+			{
+				exfat_error("too many continuations (%hhu)", continuations);
+				goto error;
+			}
 			reference_checksum = le16_to_cpu(meta1->checksum);
 			actual_checksum = exfat_start_checksum(meta1);
 			*node = allocate_node();
@@ -246,18 +317,7 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
 			}
 			init_node_meta2(*node, meta2);
 			actual_checksum = exfat_add_checksum(entry, actual_checksum);
-			/* There are two fields that contain file size. Maybe they plan
-			   to add compression support in the future and one of those
-			   fields is visible (uncompressed) size and the other is real
-			   (compressed) size. Anyway, currently it looks like exFAT does
-			   not support compression and both fields must be equal. */
-			if (le64_to_cpu(meta2->real_size) != (*node)->size)
-			{
-				exfat_error("real size does not equal to size "
-						"(%"PRIu64" != %"PRIu64")",
-						le64_to_cpu(meta2->real_size), (*node)->size);
-				goto error;
-			}
+			valid_size = le64_to_cpu(meta2->valid_size);
 			/* empty files must be marked as non-contiguous */
 			if ((*node)->size == 0 && (meta2->flags & EXFAT_FLAG_CONTIGUOUS))
 			{
@@ -269,11 +329,8 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
 			if (((*node)->flags & EXFAT_ATTRIB_DIR) &&
 				(*node)->size % CLUSTER_SIZE(*ef->sb) != 0)
 			{
-				char buffer[EXFAT_NAME_MAX + 1];
-
-				exfat_get_name(*node, buffer, EXFAT_NAME_MAX);
-				exfat_error("directory `%s' has invalid size %"PRIu64" bytes",
-						buffer, (*node)->size);
+				exfat_error("directory has invalid size %"PRIu64" bytes",
+						(*node)->size);
 				goto error;
 			}
 			--continuations;
@@ -288,17 +345,17 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
 			file_name = (const struct exfat_entry_name*) entry;
 			actual_checksum = exfat_add_checksum(entry, actual_checksum);
 
-			memcpy(namep, file_name->name, EXFAT_ENAME_MAX * sizeof(le16_t));
+			memcpy(namep, file_name->name,
+					MIN(EXFAT_ENAME_MAX,
+						((*node)->name + EXFAT_NAME_MAX - namep)) *
+					sizeof(le16_t));
 			namep += EXFAT_ENAME_MAX;
 			if (--continuations == 0)
 			{
-				if (actual_checksum != reference_checksum)
-				{
-					exfat_error("invalid checksum (0x%hx != 0x%hx)",
-							actual_checksum, reference_checksum);
+				if (!check_node(*node, actual_checksum, reference_checksum,
+						valid_size))
 					goto error;
-				}
-				if (fetch_next_entry(ef, parent, it) != 0)
+				if (!fetch_next_entry(ef, parent, it))
 					goto error;
 				return 0; /* entry completed */
 			}
@@ -310,7 +367,8 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
 			upcase = (const struct exfat_entry_upcase*) entry;
 			if (CLUSTER_INVALID(le32_to_cpu(upcase->start_cluster)))
 			{
-				exfat_error("invalid cluster in upcase table");
+				exfat_error("invalid cluster 0x%x in upcase table",
+						le32_to_cpu(upcase->start_cluster));
 				goto error;
 			}
 			if (le64_to_cpu(upcase->size) == 0 ||
@@ -331,30 +389,39 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
 			}
 			ef->upcase_chars = le64_to_cpu(upcase->size) / sizeof(le16_t);
 
-			exfat_pread(ef->dev, ef->upcase, le64_to_cpu(upcase->size),
-					exfat_c2o(ef, le32_to_cpu(upcase->start_cluster)));
+			if (exfat_pread(ef->dev, ef->upcase, le64_to_cpu(upcase->size),
+					exfat_c2o(ef, le32_to_cpu(upcase->start_cluster))) < 0)
+			{
+				exfat_error("failed to read upper case table "
+						"(%"PRIu64" bytes starting at cluster %#x)",
+						le64_to_cpu(upcase->size),
+						le32_to_cpu(upcase->start_cluster));
+				goto error;
+			}
 			break;
 
 		case EXFAT_ENTRY_BITMAP:
 			bitmap = (const struct exfat_entry_bitmap*) entry;
-			if (CLUSTER_INVALID(le32_to_cpu(bitmap->start_cluster)))
+			ef->cmap.start_cluster = le32_to_cpu(bitmap->start_cluster);
+			if (CLUSTER_INVALID(ef->cmap.start_cluster))
 			{
-				exfat_error("invalid cluster in clusters bitmap");
+				exfat_error("invalid cluster 0x%x in clusters bitmap",
+						ef->cmap.start_cluster);
 				goto error;
 			}
 			ef->cmap.size = le32_to_cpu(ef->sb->cluster_count) -
 				EXFAT_FIRST_DATA_CLUSTER;
-			if (le64_to_cpu(bitmap->size) < (ef->cmap.size + 7) / 8)
+			if (le64_to_cpu(bitmap->size) < DIV_ROUND_UP(ef->cmap.size, 8))
 			{
 				exfat_error("invalid clusters bitmap size: %"PRIu64
 						" (expected at least %u)",
-						le64_to_cpu(bitmap->size), (ef->cmap.size + 7) / 8);
+						le64_to_cpu(bitmap->size),
+						DIV_ROUND_UP(ef->cmap.size, 8));
 				goto error;
 			}
-			ef->cmap.start_cluster = le32_to_cpu(bitmap->start_cluster);
 			/* FIXME bitmap can be rather big, up to 512 MB */
 			ef->cmap.chunk_size = ef->cmap.size;
-			ef->cmap.chunk = malloc(le64_to_cpu(bitmap->size));
+			ef->cmap.chunk = malloc(BMAP_SIZE(ef->cmap.chunk_size));
 			if (ef->cmap.chunk == NULL)
 			{
 				exfat_error("failed to allocate clusters bitmap chunk "
@@ -363,8 +430,15 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
 				goto error;
 			}
 
-			exfat_pread(ef->dev, ef->cmap.chunk, le64_to_cpu(bitmap->size),
-					exfat_c2o(ef, ef->cmap.start_cluster));
+			if (exfat_pread(ef->dev, ef->cmap.chunk,
+					BMAP_SIZE(ef->cmap.chunk_size),
+					exfat_c2o(ef, ef->cmap.start_cluster)) < 0)
+			{
+				exfat_error("failed to read clusters bitmap "
+						"(%"PRIu64" bytes starting at cluster %#x)",
+						le64_to_cpu(bitmap->size), ef->cmap.start_cluster);
+				goto error;
+			}
 			break;
 
 		case EXFAT_ENTRY_LABEL:
@@ -375,20 +449,30 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
 				goto error;
 			}
 			if (utf16_to_utf8(ef->label, label->name,
-						sizeof(ef->label), EXFAT_ENAME_MAX) != 0)
+						sizeof(ef->label) - 1, EXFAT_ENAME_MAX) != 0)
 				goto error;
 			break;
 
 		default:
-			if (entry->type & EXFAT_ENTRY_VALID)
+			if (!(entry->type & EXFAT_ENTRY_VALID))
+				break; /* deleted entry, ignore it */
+			if (!(entry->type & EXFAT_ENTRY_OPTIONAL))
 			{
-				exfat_error("unknown entry type 0x%hhx", entry->type);
+				exfat_error("unknown entry type %#hhx", entry->type);
 				goto error;
 			}
+			/* optional entry, warn and skip */
+			exfat_warn("unknown entry type %#hhx", entry->type);
+			if (continuations == 0)
+			{
+				exfat_error("unexpected continuation");
+				goto error;
+			}
+			--continuations;
 			break;
 		}
 
-		if (fetch_next_entry(ef, parent, it) != 0)
+		if (!fetch_next_entry(ef, parent, it))
 			goto error;
 	}
 	/* we never reach here */
@@ -443,28 +527,55 @@ int exfat_cache_directory(struct exfat* ef, struct exfat_node* dir)
 	return 0;
 }
 
+static void tree_attach(struct exfat_node* dir, struct exfat_node* node)
+{
+	node->parent = dir;
+	if (dir->child)
+	{
+		dir->child->prev = node;
+		node->next = dir->child;
+	}
+	dir->child = node;
+}
+
+static void tree_detach(struct exfat_node* node)
+{
+	if (node->prev)
+		node->prev->next = node->next;
+	else /* this is the first node in the list */
+		node->parent->child = node->next;
+	if (node->next)
+		node->next->prev = node->prev;
+	node->parent = NULL;
+	node->prev = NULL;
+	node->next = NULL;
+}
+
 static void reset_cache(struct exfat* ef, struct exfat_node* node)
 {
-	struct exfat_node* child;
-	struct exfat_node* next;
+	char buffer[UTF8_BYTES(EXFAT_NAME_MAX) + 1];
 
-	for (child = node->child; child; child = next)
+	while (node->child)
 	{
-		reset_cache(ef, child);
-		next = child->next;
-		free(child);
+		struct exfat_node* p = node->child;
+		reset_cache(ef, p);
+		tree_detach(p);
+		free(p);
 	}
+	node->flags &= ~EXFAT_ATTRIB_CACHED;
 	if (node->references != 0)
 	{
-		char buffer[EXFAT_NAME_MAX + 1];
-		exfat_get_name(node, buffer, EXFAT_NAME_MAX);
-		exfat_warn("non-zero reference counter (%d) for `%s'",
+		exfat_get_name(node, buffer, sizeof(buffer) - 1);
+		exfat_warn("non-zero reference counter (%d) for '%s'",
 				node->references, buffer);
 	}
-	while (node->references--)
+	if (node != ef->root && (node->flags & EXFAT_ATTRIB_DIRTY))
+	{
+		exfat_get_name(node, buffer, sizeof(buffer) - 1);
+		exfat_bug("node '%s' is dirty", buffer);
+	}
+	while (node->references)
 		exfat_put_node(ef, node);
-	node->child = NULL;
-	node->flags &= ~EXFAT_ATTRIB_CACHED;
 }
 
 void exfat_reset_cache(struct exfat* ef)
@@ -472,16 +583,24 @@ void exfat_reset_cache(struct exfat* ef)
 	reset_cache(ef, ef->root);
 }
 
-void next_entry(struct exfat* ef, const struct exfat_node* parent,
+static bool next_entry(struct exfat* ef, const struct exfat_node* parent,
 		cluster_t* cluster, off_t* offset)
 {
 	*offset += sizeof(struct exfat_entry);
 	if (*offset % CLUSTER_SIZE(*ef->sb) == 0)
-		/* next cluster cannot be invalid */
+	{
 		*cluster = exfat_next_cluster(ef, parent, *cluster);
+		if (CLUSTER_INVALID(*cluster))
+		{
+			exfat_error("invalid cluster %#x while getting next entry",
+					*cluster);
+			return false;
+		}
+	}
+	return true;
 }
 
-void exfat_flush_node(struct exfat* ef, struct exfat_node* node)
+int exfat_flush_node(struct exfat* ef, struct exfat_node* node)
 {
 	cluster_t cluster;
 	off_t offset;
@@ -489,29 +608,41 @@ void exfat_flush_node(struct exfat* ef, struct exfat_node* node)
 	struct exfat_entry_meta1 meta1;
 	struct exfat_entry_meta2 meta2;
 
+	if (!(node->flags & EXFAT_ATTRIB_DIRTY))
+		return 0; /* no need to flush */
+
 	if (ef->ro)
 		exfat_bug("unable to flush node to read-only FS");
 
 	if (node->parent == NULL)
-		return; /* do not flush unlinked node */
+		return 0; /* do not flush unlinked node */
 
 	cluster = node->entry_cluster;
 	offset = node->entry_offset;
 	meta1_offset = co2o(ef, cluster, offset);
-	next_entry(ef, node->parent, &cluster, &offset);
+	if (!next_entry(ef, node->parent, &cluster, &offset))
+		return -EIO;
 	meta2_offset = co2o(ef, cluster, offset);
 
-	exfat_pread(ef->dev, &meta1, sizeof(meta1), meta1_offset);
+	if (exfat_pread(ef->dev, &meta1, sizeof(meta1), meta1_offset) < 0)
+	{
+		exfat_error("failed to read meta1 entry on flush");
+		return -EIO;
+	}
 	if (meta1.type != EXFAT_ENTRY_FILE)
 		exfat_bug("invalid type of meta1: 0x%hhx", meta1.type);
 	meta1.attrib = cpu_to_le16(node->flags);
 	exfat_unix2exfat(node->mtime, &meta1.mdate, &meta1.mtime, &meta1.mtime_cs);
 	exfat_unix2exfat(node->atime, &meta1.adate, &meta1.atime, NULL);
 
-	exfat_pread(ef->dev, &meta2, sizeof(meta2), meta2_offset);
+	if (exfat_pread(ef->dev, &meta2, sizeof(meta2), meta2_offset) < 0)
+	{
+		exfat_error("failed to read meta2 entry on flush");
+		return -EIO;
+	}
 	if (meta2.type != EXFAT_ENTRY_FILE_INFO)
 		exfat_bug("invalid type of meta2: 0x%hhx", meta2.type);
-	meta2.size = meta2.real_size = cpu_to_le64(node->size);
+	meta2.size = meta2.valid_size = cpu_to_le64(node->size);
 	meta2.start_cluster = cpu_to_le32(node->start_cluster);
 	meta2.flags = EXFAT_FLAG_ALWAYS1;
 	/* empty files must not be marked as contiguous */
@@ -521,13 +652,22 @@ void exfat_flush_node(struct exfat* ef, struct exfat_node* node)
 
 	meta1.checksum = exfat_calc_checksum(&meta1, &meta2, node->name);
 
-	exfat_pwrite(ef->dev, &meta1, sizeof(meta1), meta1_offset);
-	exfat_pwrite(ef->dev, &meta2, sizeof(meta2), meta2_offset);
+	if (exfat_pwrite(ef->dev, &meta1, sizeof(meta1), meta1_offset) < 0)
+	{
+		exfat_error("failed to write meta1 entry on flush");
+		return -EIO;
+	}
+	if (exfat_pwrite(ef->dev, &meta2, sizeof(meta2), meta2_offset) < 0)
+	{
+		exfat_error("failed to write meta2 entry on flush");
+		return -EIO;
+	}
 
 	node->flags &= ~EXFAT_ATTRIB_DIRTY;
+	return 0;
 }
 
-static void erase_entry(struct exfat* ef, struct exfat_node* node)
+static bool erase_entry(struct exfat* ef, struct exfat_node* node)
 {
 	cluster_t cluster = node->entry_cluster;
 	off_t offset = node->entry_offset;
@@ -535,42 +675,34 @@ static void erase_entry(struct exfat* ef, struct exfat_node* node)
 	uint8_t entry_type;
 
 	entry_type = EXFAT_ENTRY_FILE & ~EXFAT_ENTRY_VALID;
-	exfat_pwrite(ef->dev, &entry_type, 1, co2o(ef, cluster, offset));
+	if (exfat_pwrite(ef->dev, &entry_type, 1, co2o(ef, cluster, offset)) < 0)
+	{
+		exfat_error("failed to erase meta1 entry");
+		return false;
+	}
 
-	next_entry(ef, node->parent, &cluster, &offset);
+	if (!next_entry(ef, node->parent, &cluster, &offset))
+		return false;
 	entry_type = EXFAT_ENTRY_FILE_INFO & ~EXFAT_ENTRY_VALID;
-	exfat_pwrite(ef->dev, &entry_type, 1, co2o(ef, cluster, offset));
-
-	while (name_entries--)
+	if (exfat_pwrite(ef->dev, &entry_type, 1, co2o(ef, cluster, offset)) < 0)
 	{
-		next_entry(ef, node->parent, &cluster, &offset);
-		entry_type = EXFAT_ENTRY_FILE_NAME & ~EXFAT_ENTRY_VALID;
-		exfat_pwrite(ef->dev, &entry_type, 1, co2o(ef, cluster, offset));
+		exfat_error("failed to erase meta2 entry");
+		return false;
 	}
-}
 
-static void tree_detach(struct exfat_node* node)
-{
-	if (node->prev)
-		node->prev->next = node->next;
-	else /* this is the first node in the list */
-		node->parent->child = node->next;
-	if (node->next)
-		node->next->prev = node->prev;
-	node->parent = NULL;
-	node->prev = NULL;
-	node->next = NULL;
-}
-
-static void tree_attach(struct exfat_node* dir, struct exfat_node* node)
-{
-	node->parent = dir;
-	if (dir->child)
+	while (name_entries--)
 	{
-		dir->child->prev = node;
-		node->next = dir->child;
+		if (!next_entry(ef, node->parent, &cluster, &offset))
+			return false;
+		entry_type = EXFAT_ENTRY_FILE_NAME & ~EXFAT_ENTRY_VALID;
+		if (exfat_pwrite(ef->dev, &entry_type, 1,
+				co2o(ef, cluster, offset)) < 0)
+		{
+			exfat_error("failed to erase name entry");
+			return false;
+		}
 	}
-	dir->child = node;
+	return true;
 }
 
 static int shrink_directory(struct exfat* ef, struct exfat_node* dir,
@@ -580,7 +712,6 @@ static int shrink_directory(struct exfat* ef, struct exfat_node* dir,
 	const struct exfat_node* last_node;
 	uint64_t entries = 0;
 	uint64_t new_size;
-	int rc;
 
 	if (!(dir->flags & EXFAT_ATTRIB_DIR))
 		exfat_bug("attempted to shrink a file");
@@ -616,10 +747,7 @@ static int shrink_directory(struct exfat* ef, struct exfat_node* dir,
 		new_size = CLUSTER_SIZE(*ef->sb);
 	if (new_size == dir->size)
 		return 0;
-	rc = exfat_truncate(ef, dir, new_size);
-	if (rc != 0)
-		return rc;
-	return 0;
+	return exfat_truncate(ef, dir, new_size, true);
 }
 
 static int delete(struct exfat* ef, struct exfat_node* node)
@@ -629,13 +757,23 @@ static int delete(struct exfat* ef, struct exfat_node* node)
 	int rc;
 
 	exfat_get_node(parent);
-	erase_entry(ef, node);
+	if (!erase_entry(ef, node))
+	{
+		exfat_put_node(ef, parent);
+		return -EIO;
+	}
 	exfat_update_mtime(parent);
 	tree_detach(node);
 	rc = shrink_directory(ef, parent, deleted_offset);
-	exfat_put_node(ef, parent);
-	/* file clusters will be freed when node reference counter becomes 0 */
 	node->flags |= EXFAT_ATTRIB_UNLINKED;
+	if (rc != 0)
+	{
+		exfat_flush_node(ef, parent);
+		exfat_put_node(ef, parent);
+		return rc;
+	}
+	rc = exfat_flush_node(ef, parent);
+	exfat_put_node(ef, parent);
 	return rc;
 }
 
@@ -648,10 +786,14 @@ int exfat_unlink(struct exfat* ef, struct exfat_node* node)
 
 int exfat_rmdir(struct exfat* ef, struct exfat_node* node)
 {
+	int rc;
+
 	if (!(node->flags & EXFAT_ATTRIB_DIR))
 		return -ENOTDIR;
 	/* check that directory is empty */
-	exfat_cache_directory(ef, node);
+	rc = exfat_cache_directory(ef, node);
+	if (rc != 0)
+		return rc;
 	if (node->child)
 		return -ENOTEMPTY;
 	return delete(ef, node);
@@ -662,7 +804,7 @@ static int grow_directory(struct exfat* ef, struct exfat_node* dir,
 {
 	return exfat_truncate(ef, dir,
 			DIV_ROUND_UP(asize + difference, CLUSTER_SIZE(*ef->sb))
-				* CLUSTER_SIZE(*ef->sb));
+				* CLUSTER_SIZE(*ef->sb), true);
 }
 
 static int find_slot(struct exfat* ef, struct exfat_node* dir,
@@ -700,7 +842,7 @@ static int find_slot(struct exfat* ef, struct exfat_node* dir,
 				return rc;
 			}
 		}
-		if (fetch_next_entry(ef, dir, &it) != 0)
+		if (!fetch_next_entry(ef, dir, &it))
 		{
 			closedir(&it);
 			return -EIO;
@@ -746,17 +888,34 @@ static int write_entry(struct exfat* ef, struct exfat_node* dir,
 
 	meta1.checksum = exfat_calc_checksum(&meta1, &meta2, node->name);
 
-	exfat_pwrite(ef->dev, &meta1, sizeof(meta1), co2o(ef, cluster, offset));
-	next_entry(ef, dir, &cluster, &offset);
-	exfat_pwrite(ef->dev, &meta2, sizeof(meta2), co2o(ef, cluster, offset));
+	if (exfat_pwrite(ef->dev, &meta1, sizeof(meta1),
+			co2o(ef, cluster, offset)) < 0)
+	{
+		exfat_error("failed to write meta1 entry");
+		return -EIO;
+	}
+	if (!next_entry(ef, dir, &cluster, &offset))
+		return -EIO;
+	if (exfat_pwrite(ef->dev, &meta2, sizeof(meta2),
+			co2o(ef, cluster, offset)) < 0)
+	{
+		exfat_error("failed to write meta2 entry");
+		return -EIO;
+	}
 	for (i = 0; i < name_entries; i++)
 	{
 		struct exfat_entry_name name_entry = {EXFAT_ENTRY_FILE_NAME, 0};
 		memcpy(name_entry.name, node->name + i * EXFAT_ENAME_MAX,
-				EXFAT_ENAME_MAX * sizeof(le16_t));
-		next_entry(ef, dir, &cluster, &offset);
-		exfat_pwrite(ef->dev, &name_entry, sizeof(name_entry),
-				co2o(ef, cluster, offset));
+				MIN(EXFAT_ENAME_MAX, EXFAT_NAME_MAX - i * EXFAT_ENAME_MAX) *
+				sizeof(le16_t));
+		if (!next_entry(ef, dir, &cluster, &offset))
+			return -EIO;
+		if (exfat_pwrite(ef->dev, &name_entry, sizeof(name_entry),
+				co2o(ef, cluster, offset)) < 0)
+		{
+			exfat_error("failed to write name entry");
+			return -EIO;
+		}
 	}
 
 	init_node_meta1(node, &meta1);
@@ -794,6 +953,12 @@ static int create(struct exfat* ef, const char* path, uint16_t attrib)
 		return rc;
 	}
 	rc = write_entry(ef, dir, name, cluster, offset, attrib);
+	if (rc != 0)
+	{
+		exfat_put_node(ef, dir);
+		return rc;
+	}
+	rc = exfat_flush_node(ef, dir);
 	exfat_put_node(ef, dir);
 	return rc;
 }
@@ -808,14 +973,21 @@ int exfat_mkdir(struct exfat* ef, const char* path)
 	int rc;
 	struct exfat_node* node;
 
-	rc = create(ef, path, EXFAT_ATTRIB_ARCH | EXFAT_ATTRIB_DIR);
+	rc = create(ef, path, EXFAT_ATTRIB_DIR);
 	if (rc != 0)
 		return rc;
 	rc = exfat_lookup(ef, &node, path);
 	if (rc != 0)
 		return 0;
 	/* directories always have at least one cluster */
-	rc = exfat_truncate(ef, node, CLUSTER_SIZE(*ef->sb));
+	rc = exfat_truncate(ef, node, CLUSTER_SIZE(*ef->sb), true);
+	if (rc != 0)
+	{
+		delete(ef, node);
+		exfat_put_node(ef, node);
+		return rc;
+	}
+	rc = exfat_flush_node(ef, node);
 	if (rc != 0)
 	{
 		delete(ef, node);
@@ -826,7 +998,7 @@ int exfat_mkdir(struct exfat* ef, const char* path)
 	return 0;
 }
 
-static void rename_entry(struct exfat* ef, struct exfat_node* dir,
+static int rename_entry(struct exfat* ef, struct exfat_node* dir,
 		struct exfat_node* node, const le16_t* name, cluster_t new_cluster,
 		off_t new_offset)
 {
@@ -838,40 +1010,65 @@ static void rename_entry(struct exfat* ef, struct exfat_node* dir,
 	const int name_entries = DIV_ROUND_UP(name_length, EXFAT_ENAME_MAX);
 	int i;
 
-	exfat_pread(ef->dev, &meta1, sizeof(meta1),
-			co2o(ef, old_cluster, old_offset));
-	next_entry(ef, node->parent, &old_cluster, &old_offset);
-	exfat_pread(ef->dev, &meta2, sizeof(meta2),
-			co2o(ef, old_cluster, old_offset));
+	if (exfat_pread(ef->dev, &meta1, sizeof(meta1),
+			co2o(ef, old_cluster, old_offset)) < 0)
+	{
+		exfat_error("failed to read meta1 entry on rename");
+		return -EIO;
+	}
+	if (!next_entry(ef, node->parent, &old_cluster, &old_offset))
+		return -EIO;
+	if (exfat_pread(ef->dev, &meta2, sizeof(meta2),
+			co2o(ef, old_cluster, old_offset)) < 0)
+	{
+		exfat_error("failed to read meta2 entry on rename");
+		return -EIO;
+	}
 	meta1.continuations = 1 + name_entries;
 	meta2.name_hash = exfat_calc_name_hash(ef, name);
 	meta2.name_length = name_length;
 	meta1.checksum = exfat_calc_checksum(&meta1, &meta2, name);
 
-	erase_entry(ef, node);
+	if (!erase_entry(ef, node))
+		return -EIO;
 
 	node->entry_cluster = new_cluster;
 	node->entry_offset = new_offset;
 
-	exfat_pwrite(ef->dev, &meta1, sizeof(meta1),
-			co2o(ef, new_cluster, new_offset));
-	next_entry(ef, dir, &new_cluster, &new_offset);
-	exfat_pwrite(ef->dev, &meta2, sizeof(meta2),
-			co2o(ef, new_cluster, new_offset));
+	if (exfat_pwrite(ef->dev, &meta1, sizeof(meta1),
+			co2o(ef, new_cluster, new_offset)) < 0)
+	{
+		exfat_error("failed to write meta1 entry on rename");
+		return -EIO;
+	}
+	if (!next_entry(ef, dir, &new_cluster, &new_offset))
+		return -EIO;
+	if (exfat_pwrite(ef->dev, &meta2, sizeof(meta2),
+			co2o(ef, new_cluster, new_offset)) < 0)
+	{
+		exfat_error("failed to write meta2 entry on rename");
+		return -EIO;
+	}
 
 	for (i = 0; i < name_entries; i++)
 	{
 		struct exfat_entry_name name_entry = {EXFAT_ENTRY_FILE_NAME, 0};
 		memcpy(name_entry.name, name + i * EXFAT_ENAME_MAX,
 				EXFAT_ENAME_MAX * sizeof(le16_t));
-		next_entry(ef, dir, &new_cluster, &new_offset);
-		exfat_pwrite(ef->dev, &name_entry, sizeof(name_entry),
-				co2o(ef, new_cluster, new_offset));
+		if (!next_entry(ef, dir, &new_cluster, &new_offset))
+			return -EIO;
+		if (exfat_pwrite(ef->dev, &name_entry, sizeof(name_entry),
+				co2o(ef, new_cluster, new_offset)) < 0)
+		{
+			exfat_error("failed to write name entry on rename");
+			return -EIO;
+		}
 	}
 
 	memcpy(node->name, name, (EXFAT_NAME_MAX + 1) * sizeof(le16_t));
 	tree_detach(node);
 	tree_attach(dir, node);
+	return 0;
 }
 
 int exfat_rename(struct exfat* ef, const char* old_path, const char* new_path)
@@ -894,29 +1091,52 @@ int exfat_rename(struct exfat* ef, const char* old_path, const char* new_path)
 		exfat_put_node(ef, node);
 		return rc;
 	}
+
+	/* check that target is not a subdirectory of the source */
+	if (node->flags & EXFAT_ATTRIB_DIR)
+	{
+		struct exfat_node* p;
+
+		for (p = dir; p; p = p->parent)
+			if (node == p)
+			{
+				if (existing != NULL)
+					exfat_put_node(ef, existing);
+				exfat_put_node(ef, dir);
+				exfat_put_node(ef, node);
+				return -EINVAL;
+			}
+	}
+
 	if (existing != NULL)
 	{
-		if (existing->flags & EXFAT_ATTRIB_DIR)
+		/* remove target if it's not the same node as source */
+		if (existing != node)
 		{
-			if (node->flags & EXFAT_ATTRIB_DIR)
-				rc = exfat_rmdir(ef, existing);
+			if (existing->flags & EXFAT_ATTRIB_DIR)
+			{
+				if (node->flags & EXFAT_ATTRIB_DIR)
+					rc = exfat_rmdir(ef, existing);
+				else
+					rc = -ENOTDIR;
+			}
 			else
-				rc = -ENOTDIR;
+			{
+				if (!(node->flags & EXFAT_ATTRIB_DIR))
+					rc = exfat_unlink(ef, existing);
+				else
+					rc = -EISDIR;
+			}
+			exfat_put_node(ef, existing);
+			if (rc != 0)
+			{
+				exfat_put_node(ef, dir);
+				exfat_put_node(ef, node);
+				return rc;
+			}
 		}
 		else
-		{
-			if (!(node->flags & EXFAT_ATTRIB_DIR))
-				rc = exfat_unlink(ef, existing);
-			else
-				rc = -EISDIR;
-		}
-		exfat_put_node(ef, existing);
-		if (rc != 0)
-		{
-			exfat_put_node(ef, dir);
-			exfat_put_node(ef, node);
-			return rc;
-		}
+			exfat_put_node(ef, existing);
 	}
 
 	rc = find_slot(ef, dir, &cluster, &offset,
@@ -927,10 +1147,10 @@ int exfat_rename(struct exfat* ef, const char* old_path, const char* new_path)
 		exfat_put_node(ef, node);
 		return rc;
 	}
-	rename_entry(ef, dir, node, name, cluster, offset);
+	rc = rename_entry(ef, dir, node, name, cluster, offset);
 	exfat_put_node(ef, dir);
 	exfat_put_node(ef, node);
-	return 0;
+	return rc;
 }
 
 void exfat_utimes(struct exfat_node* node, const struct timespec tv[2])
@@ -982,7 +1202,7 @@ static int find_label(struct exfat* ef, cluster_t* cluster, off_t* offset)
 			return 0;
 		}
 
-		if (fetch_next_entry(ef, ef->root, &it) != 0)
+		if (!fetch_next_entry(ef, ef->root, &it))
 		{
 			closedir(&it);
 			return -EIO;
@@ -1015,7 +1235,12 @@ int exfat_set_label(struct exfat* ef, const char* label)
 	if (entry.length == 0)
 		entry.type ^= EXFAT_ENTRY_VALID;
 
-	exfat_pwrite(ef->dev, &entry, sizeof(struct exfat_entry_label),
-			co2o(ef, cluster, offset));
+	if (exfat_pwrite(ef->dev, &entry, sizeof(struct exfat_entry_label),
+			co2o(ef, cluster, offset)) < 0)
+	{
+		exfat_error("failed to write label entry");
+		return -EIO;
+	}
+	strcpy(ef->label, label);
 	return 0;
 }