Re: [syzbot] [hfs?] KMSAN: uninit-value in hfsplus_bnode_find

[Edward Adam Davis]

#syz test

diff --git a/fs/hfsplus/bnode.c b/fs/hfsplus/bnode.c
index 250a226336ea..56a046ba4d54 100644
--- a/fs/hfsplus/bnode.c
+++ b/fs/hfsplus/bnode.c
@@ -576,7 +576,10 @@ struct hfs_bnode *hfs_bnode_find(struct hfs_btree *tree, u32 num)
 		goto node_error;
 	}
 
-	rec_off = tree->node_size - 2;
+	if (tree->node_size < 2)
+		goto node_error;
+	else
+		rec_off = tree->node_size - 2;
 	off = hfs_bnode_read_u16(node, rec_off);
 	if (off != sizeof(struct hfs_bnode_desc))
 		goto node_error;