diff --git a/fs/ubifs/commit.c b/fs/ubifs/commit.c
index 1bd01de..87cd0ea 100644
--- a/fs/ubifs/commit.c
+++ b/fs/ubifs/commit.c
@@ -182,7 +182,7 @@
 	c->mst_node->root_len    = cpu_to_le32(zroot.len);
 	c->mst_node->ihead_lnum  = cpu_to_le32(c->ihead_lnum);
 	c->mst_node->ihead_offs  = cpu_to_le32(c->ihead_offs);
-	c->mst_node->index_size  = cpu_to_le64(c->old_idx_sz);
+	c->mst_node->index_size  = cpu_to_le64(c->bi.old_idx_sz);
 	c->mst_node->lpt_lnum    = cpu_to_le32(c->lpt_lnum);
 	c->mst_node->lpt_offs    = cpu_to_le32(c->lpt_offs);
 	c->mst_node->nhead_lnum  = cpu_to_le32(c->nhead_lnum);