diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c
index d3cb27487c706..3bcf98d01733c 100644
--- a/fs/jfs/jfs_dmap.c
+++ b/fs/jfs/jfs_dmap.c
@@ -155,7 +155,7 @@ int dbMount(struct inode *ipbmap)
 	struct bmap *bmp;
 	struct dbmap_disk *dbmp_le;
 	struct metapage *mp;
-	int i;
+	int i, err;
 
 	/*
 	 * allocate/initialize the in-memory bmap descriptor
@@ -170,8 +170,8 @@ int dbMount(struct inode *ipbmap)
 			   BMAPBLKNO << JFS_SBI(ipbmap->i_sb)->l2nbperpage,
 			   PSIZE, 0);
 	if (mp == NULL) {
-		kfree(bmp);
-		return -EIO;
+		err = -EIO;
+		goto err_kfree_bmp;
 	}
 
 	/* copy the on-disk bmap descriptor to its in-memory version. */
@@ -181,9 +181,8 @@ int dbMount(struct inode *ipbmap)
 	bmp->db_l2nbperpage = le32_to_cpu(dbmp_le->dn_l2nbperpage);
 	bmp->db_numag = le32_to_cpu(dbmp_le->dn_numag);
 	if (!bmp->db_numag) {
-		release_metapage(mp);
-		kfree(bmp);
-		return -EINVAL;
+		err = -EINVAL;
+		goto err_release_metapage;
 	}
 
 	bmp->db_maxlevel = le32_to_cpu(dbmp_le->dn_maxlevel);
@@ -194,6 +193,11 @@ int dbMount(struct inode *ipbmap)
 	bmp->db_agwidth = le32_to_cpu(dbmp_le->dn_agwidth);
 	bmp->db_agstart = le32_to_cpu(dbmp_le->dn_agstart);
 	bmp->db_agl2size = le32_to_cpu(dbmp_le->dn_agl2size);
+	if (bmp->db_agl2size > L2MAXL2SIZE - L2MAXAG) {
+		err = -EINVAL;
+		goto err_release_metapage;
+	}
+
 	for (i = 0; i < MAXAG; i++)
 		bmp->db_agfree[i] = le64_to_cpu(dbmp_le->dn_agfree[i]);
 	bmp->db_agsize = le64_to_cpu(dbmp_le->dn_agsize);
@@ -214,6 +218,12 @@ int dbMount(struct inode *ipbmap)
 	BMAP_LOCK_INIT(bmp);
 
 	return (0);
+
+err_release_metapage:
+	release_metapage(mp);
+err_kfree_bmp:
+	kfree(bmp);
+	return err;
 }