diff --git a/super.c b/super.c
index 2f83c12..5a21d35 100644
--- a/super.c
+++ b/super.c
@@ -2520,7 +2520,8 @@ static unsigned int udf_count_free(struct super_block *sb)
                struct logicalVolIntegrityDesc *lvid =
                        (struct logicalVolIntegrityDesc *)
                        sbi->s_lvid_bh->b_data;
-               if (le32_to_cpu(lvid->numOfPartitions) > part) {
+               if (le32_to_cpu(lvid->numOfPartitions) > part
+                       && le32_to_cpu(lvid->lengthOfImpUse) > part) {
                        accum = le32_to_cpu(
                                        lvid->freeSpaceTable[part]);
                        if (accum == 0xFFFFFFFF)