diff --git a/fsck.c b/fsck.c
index dd4822ba1b..5acc982a7c 100644
--- a/fsck.c
+++ b/fsck.c
@@ -308,7 +308,7 @@ static int fsck_walk_tree(struct tree *tree, void *data, struct fsck_options *op
 		return -1;
 
 	name = fsck_get_object_name(options, &tree->object.oid);
-	if (init_tree_desc_gently(&desc, tree->buffer, tree->size))
+	if (init_tree_desc_gently(&desc, tree->buffer, tree->size, 0))
 		return -1;
 	while (tree_entry_gently(&desc, &entry)) {
 		struct object *obj;
@@ -578,7 +578,7 @@ static int fsck_tree(const struct object_id *tree_oid,
 	const char *o_name;
 	struct name_stack df_dup_candidates = { NULL };
 
-	if (init_tree_desc_gently(&desc, buffer, size)) {
+	if (init_tree_desc_gently(&desc, buffer, size, 0)) {
 		retval += report(options, tree_oid, OBJ_TREE,
 				 FSCK_MSG_BAD_TREE,
 				 "cannot be parsed as a tree");
diff --git a/packfile.c b/packfile.c
index 8e812a84a3..e5b1d0ed76 100644
--- a/packfile.c
+++ b/packfile.c
@@ -2243,7 +2243,7 @@ static int add_promisor_object(const struct object_id *oid,
 		struct tree *tree = (struct tree *)obj;
 		struct tree_desc desc;
 		struct name_entry entry;
-		if (init_tree_desc_gently(&desc, tree->buffer, tree->size))
+		if (init_tree_desc_gently(&desc, tree->buffer, tree->size, 0))
 			/*
 			 * Error messages are given when packs are
 			 * verified, so do not print any here.
diff --git a/tree-walk.c b/tree-walk.c
index 506234b4b8..74f4d710e8 100644
--- a/tree-walk.c
+++ b/tree-walk.c
@@ -47,17 +47,20 @@ static int decode_tree_entry(struct tree_desc *desc, const char *buf, unsigned l
 
 	/* Initialize the descriptor entry */
 	desc->entry.path = path;
-	desc->entry.mode = canon_mode(mode);
+	desc->entry.mode = (desc->flags & TREE_DESC_RAW_MODES) ? mode : canon_mode(mode);
 	desc->entry.pathlen = len - 1;
 	oidread(&desc->entry.oid, (const unsigned char *)path + len);
 
 	return 0;
 }
 
-static int init_tree_desc_internal(struct tree_desc *desc, const void *buffer, unsigned long size, struct strbuf *err)
+static int init_tree_desc_internal(struct tree_desc *desc, const void *buffer,
+				   unsigned long size, struct strbuf *err,
+				   enum tree_desc_flags flags)
 {
 	desc->buffer = buffer;
 	desc->size = size;
+	desc->flags = flags;
 	if (size)
 		return decode_tree_entry(desc, buffer, size, err);
 	return 0;
@@ -66,15 +69,16 @@ static int init_tree_desc_internal(struct tree_desc *desc, const void *buffer, u
 void init_tree_desc(struct tree_desc *desc, const void *buffer, unsigned long size)
 {
 	struct strbuf err = STRBUF_INIT;
-	if (init_tree_desc_internal(desc, buffer, size, &err))
+	if (init_tree_desc_internal(desc, buffer, size, &err, 0))
 		die("%s", err.buf);
 	strbuf_release(&err);
 }
 
-int init_tree_desc_gently(struct tree_desc *desc, const void *buffer, unsigned long size)
+int init_tree_desc_gently(struct tree_desc *desc, const void *buffer, unsigned long size,
+			  enum tree_desc_flags flags)
 {
 	struct strbuf err = STRBUF_INIT;
-	int result = init_tree_desc_internal(desc, buffer, size, &err);
+	int result = init_tree_desc_internal(desc, buffer, size, &err, flags);
 	if (result)
 		error("%s", err.buf);
 	strbuf_release(&err);
diff --git a/tree-walk.h b/tree-walk.h
index a5058469e9..6305d53150 100644
--- a/tree-walk.h
+++ b/tree-walk.h
@@ -34,6 +34,11 @@ struct tree_desc {
 
 	/* counts the number of bytes left in the `buffer`. */
 	unsigned int size;
+
+	/* option flags passed via init_tree_desc_gently() */
+	enum tree_desc_flags {
+		TREE_DESC_RAW_MODES = (1 << 0),
+	} flags;
 };
 
 /**
@@ -79,7 +84,8 @@ int update_tree_entry_gently(struct tree_desc *);
  */
 void init_tree_desc(struct tree_desc *desc, const void *buf, unsigned long size);
 
-int init_tree_desc_gently(struct tree_desc *desc, const void *buf, unsigned long size);
+int init_tree_desc_gently(struct tree_desc *desc, const void *buf, unsigned long size,
+			  enum tree_desc_flags flags);
 
 /*
  * Visit the next entry in a tree. Returns 1 when there are more entries