diff --git a/fs/hfs/bfind.c b/fs/hfs/bfind.c
index f13f1494d4f..f8452a0eab5 100644
--- a/fs/hfs/bfind.c
+++ b/fs/hfs/bfind.c
@@ -52,6 +52,10 @@ int __hfs_brec_find(struct hfs_bnode *bnode, struct hfs_find_data *fd)
 		rec = (e + b) / 2;
 		len = hfs_brec_lenoff(bnode, rec, &off);
 		keylen = hfs_brec_keylen(bnode, rec);
+		if (keylen == HFS_BAD_KEYLEN) {
+			res = -EINVAL;
+			goto done;
+		}
 		hfs_bnode_read(bnode, fd->key, off, keylen);
 		cmpval = bnode->tree->keycmp(fd->key, fd->search_key);
 		if (!cmpval) {
@@ -67,6 +71,10 @@ int __hfs_brec_find(struct hfs_bnode *bnode, struct hfs_find_data *fd)
 	if (rec != e && e >= 0) {
 		len = hfs_brec_lenoff(bnode, e, &off);
 		keylen = hfs_brec_keylen(bnode, e);
+		if (keylen == HFS_BAD_KEYLEN) {
+			res = -EINVAL;
+			goto done;
+		}
 		hfs_bnode_read(bnode, fd->key, off, keylen);
 	}
 done:
@@ -198,6 +206,10 @@ int hfs_brec_goto(struct hfs_find_data *fd, int cnt)
 
 	len = hfs_brec_lenoff(bnode, fd->record, &off);
 	keylen = hfs_brec_keylen(bnode, fd->record);
+	if (keylen == HFS_BAD_KEYLEN) {
+		res = -EINVAL;
+		goto out;
+	}
 	fd->keyoffset = off;
 	fd->keylength = keylen;
 	fd->entryoffset = off + keylen;
diff --git a/fs/hfs/brec.c b/fs/hfs/brec.c
index 5c87cf4801f..8626ee375ea 100644
--- a/fs/hfs/brec.c
+++ b/fs/hfs/brec.c
@@ -44,10 +44,21 @@ u16 hfs_brec_keylen(struct hfs_bnode *node, u16 rec)
 		recoff = hfs_bnode_read_u16(node, node->tree->node_size - (rec + 1) * 2);
 		if (!recoff)
 			return 0;
-		if (node->tree->attributes & HFS_TREE_BIGKEYS)
+		if (node->tree->attributes & HFS_TREE_BIGKEYS) {
 			retval = hfs_bnode_read_u16(node, recoff) + 2;
-		else
+			if (retval > node->tree->max_key_len + 2) {
+				printk(KERN_ERR "hfs: keylen %d too large\n",
+					retval);
+				retval = HFS_BAD_KEYLEN;
+			}
+		} else {
 			retval = (hfs_bnode_read_u8(node, recoff) | 1) + 1;
+			if (retval > node->tree->max_key_len + 1) {
+				printk(KERN_ERR "hfs: keylen %d too large\n",
+					retval);
+				retval = HFS_BAD_KEYLEN;
+			}
+		}
 	}
 	return retval;
 }
diff --git a/fs/hfs/btree.c b/fs/hfs/btree.c
index 8a3a650abc8..31284c77bba 100644
--- a/fs/hfs/btree.c
+++ b/fs/hfs/btree.c
@@ -81,6 +81,17 @@ struct hfs_btree *hfs_btree_open(struct super_block *sb, u32 id, btree_keycmp ke
 		goto fail_page;
 	if (!tree->node_count)
 		goto fail_page;
+	if ((id == HFS_EXT_CNID) && (tree->max_key_len != HFS_MAX_EXT_KEYLEN)) {
+		printk(KERN_ERR "hfs: invalid extent max_key_len %d\n",
+			tree->max_key_len);
+		goto fail_page;
+	}
+	if ((id == HFS_CAT_CNID) && (tree->max_key_len != HFS_MAX_CAT_KEYLEN)) {
+		printk(KERN_ERR "hfs: invalid catalog max_key_len %d\n",
+			tree->max_key_len);
+		goto fail_page;
+	}
+
 	tree->node_size_shift = ffs(size) - 1;
 	tree->pages_per_bnode = (tree->node_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
 
@@ -89,9 +100,9 @@ struct hfs_btree *hfs_btree_open(struct super_block *sb, u32 id, btree_keycmp ke
 	return tree;
 
  fail_page:
-	tree->inode->i_mapping->a_ops = &hfs_aops;
 	page_cache_release(page);
  free_tree:
+	tree->inode->i_mapping->a_ops = &hfs_aops;
 	iput(tree->inode);
 	kfree(tree);
 	return NULL;
diff --git a/fs/hfs/hfs.h b/fs/hfs/hfs.h
index 1445e3a56ed..c6aae61adfe 100644
--- a/fs/hfs/hfs.h
+++ b/fs/hfs/hfs.h
@@ -28,6 +28,8 @@
 #define HFS_MAX_NAMELEN		128
 #define HFS_MAX_VALENCE		32767U
 
+#define HFS_BAD_KEYLEN		0xFF
+
 /* Meanings of the drAtrb field of the MDB,
  * Reference: _Inside Macintosh: Files_ p. 2-61
  */
@@ -167,6 +169,9 @@ typedef union hfs_btree_key {
 	struct hfs_ext_key ext;
 } hfs_btree_key;
 
+#define HFS_MAX_CAT_KEYLEN	(sizeof(struct hfs_cat_key) - sizeof(u8))
+#define HFS_MAX_EXT_KEYLEN	(sizeof(struct hfs_ext_key) - sizeof(u8))
+
 typedef union hfs_btree_key btree_key;
 
 struct hfs_extent {