diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c
index 4d59373f9e6c..11c77757ead9 100644
--- a/fs/jfs/jfs_dmap.c
+++ b/fs/jfs/jfs_dmap.c
@@ -87,7 +87,7 @@ static int dbAllocCtl(struct bmap * bmp, s64 nblocks, int l2nb, s64 blkno,
 static int dbExtend(struct inode *ip, s64 blkno, s64 nblocks, s64 addnblocks);
 static int dbFindBits(u32 word, int l2nb);
 static int dbFindCtl(struct bmap * bmp, int l2nb, int level, s64 * blkno);
-static int dbFindLeaf(dmtree_t * tp, int l2nb, int *leafidx);
+static int dbFindLeaf(dmtree_t *tp, int l2nb, int *leafidx, bool is_ctl);
 static int dbFreeBits(struct bmap * bmp, struct dmap * dp, s64 blkno,
 		      int nblocks);
 static int dbFreeDmap(struct bmap * bmp, struct dmap * dp, s64 blkno,
@@ -1717,7 +1717,7 @@ static int dbFindCtl(struct bmap * bmp, int l2nb, int level, s64 * blkno)
 		 * dbFindLeaf() returns the index of the leaf at which
 		 * free space was found.
 		 */
-		rc = dbFindLeaf((dmtree_t *) dcp, l2nb, &leafidx);
+		rc = dbFindLeaf((dmtree_t *) dcp, l2nb, &leafidx, true);
 
 		/* release the buffer.
 		 */
@@ -1964,7 +1964,7 @@ dbAllocDmapLev(struct bmap * bmp,
 	 * free space.  if sufficient free space is found, dbFindLeaf()
 	 * returns the index of the leaf at which free space was found.
 	 */
-	if (dbFindLeaf((dmtree_t *) & dp->tree, l2nb, &leafidx))
+	if (dbFindLeaf((dmtree_t *) &dp->tree, l2nb, &leafidx, false))
 		return -ENOSPC;
 
 	if (leafidx < 0)
@@ -2928,14 +2928,18 @@ static void dbAdjTree(dmtree_t * tp, int leafno, int newval)
  *	leafidx	- return pointer to be set to the index of the leaf
  *		  describing at least l2nb free blocks if sufficient
  *		  free blocks are found.
+ *	is_ctl	- determines if the tree is of type ctl
  *
  * RETURN VALUES:
  *	0	- success
  *	-ENOSPC	- insufficient free blocks.
  */
-static int dbFindLeaf(dmtree_t * tp, int l2nb, int *leafidx)
+static int dbFindLeaf(dmtree_t *tp, int l2nb, int *leafidx, bool is_ctl)
 {
 	int ti, n = 0, k, x = 0;
+	int max_size;
+
+	max_size = is_ctl ? CTLTREESIZE : TREESIZE;
 
 	/* first check the root of the tree to see if there is
 	 * sufficient free space.
@@ -2956,6 +2960,8 @@ static int dbFindLeaf(dmtree_t * tp, int l2nb, int *leafidx)
 			/* sufficient free space found.  move to the next
 			 * level (or quit if this is the last level).
 			 */
+			if (x + n > max_size)
+				return -ENOSPC;
 			if (l2nb <= tp->dmt_stree[x + n])
 				break;
 		}