diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c
index a3eb1e826947..6a5df296fdc8 100644
--- a/fs/jfs/jfs_dmap.c
+++ b/fs/jfs/jfs_dmap.c
@@ -467,6 +467,10 @@ dbUpdatePMap(struct inode *ipbmap,
 	lastlblkno = 0;
 	for (rem = nblocks; rem > 0; rem -= nblks, blkno += nblks) {
 		/* get the buffer for the current dmap. */
+
+		if(bmp->db_l2nbperpage > L2BPERDMAP)
+			return -EIO;
+
 		lblkno = BLKTODMAP(blkno, bmp->db_l2nbperpage);
 		if (lblkno != lastlblkno) {
 			if (mp) {