1 files changed, 27 insertions, 4 deletions

diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c
index 3ad0a33e0..2f452b5ee 100644
--- a/fs/jfs/jfs_dmap.c
+++ b/fs/jfs/jfs_dmap.c
@@ -100,7 +100,7 @@ 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,
@@ -191,7 +191,14 @@ int dbMount(struct inode *ipbmap)
 	dbmp_le = (struct dbmap_disk *) mp->data;
 	bmp->db_mapsize = le64_to_cpu(dbmp_le->dn_mapsize);
 	bmp->db_nfree = le64_to_cpu(dbmp_le->dn_nfree);
+
 	bmp->db_l2nbperpage = le32_to_cpu(dbmp_le->dn_l2nbperpage);
+	if (bmp->db_l2nbperpage > L2PSIZE - L2MINBLOCKSIZE ||
+		bmp->db_l2nbperpage < 0) {
+		err = -EINVAL;
+		goto err_release_metapage;
+	}
+
 	bmp->db_numag = le32_to_cpu(dbmp_le->dn_numag);
 	if (!bmp->db_numag) {
 		err = -EINVAL;
@@ -201,6 +208,12 @@ int dbMount(struct inode *ipbmap)
 	bmp->db_maxlevel = le32_to_cpu(dbmp_le->dn_maxlevel);
 	bmp->db_maxag = le32_to_cpu(dbmp_le->dn_maxag);
 	bmp->db_agpref = le32_to_cpu(dbmp_le->dn_agpref);
+	if (bmp->db_maxag >= MAXAG || bmp->db_maxag < 0 ||
+		bmp->db_agpref >= MAXAG || bmp->db_agpref < 0) {
+		err = -EINVAL;
+		goto err_release_metapage;
+	}
+
 	bmp->db_aglevel = le32_to_cpu(dbmp_le->dn_aglevel);
 	bmp->db_agheight = le32_to_cpu(dbmp_le->dn_agheight);
 	bmp->db_agwidth = le32_to_cpu(dbmp_le->dn_agwidth);
@@ -276,6 +289,7 @@ int dbUnmount(struct inode *ipbmap, int mounterror)
 
 	/* free the memory for the in-memory bmap. */
 	kfree(bmp);
+	JFS_SBI(ipbmap->i_sb)->bmap = NULL;
 
 	return (0);
 }
@@ -1784,7 +1798,7 @@ 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.
 		 */
@@ -2031,9 +2045,12 @@ 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)
+		return -EIO;
+
 	/* determine the block number within the file system corresponding
 	 * to the leaf at which free space was found.
 	 */
@@ -2988,14 +3005,18 @@ 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.
@@ -3016,6 +3037,8 @@ 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;
 		}