diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c
index d32714094375b72695bcacdfcf7cdd866be2ff05..501b7f8b739fc2ed8079c0bc664481933d8d9d74 100644
--- a/fs/nilfs2/the_nilfs.c
+++ b/fs/nilfs2/the_nilfs.c
@@ -409,6 +409,12 @@ static int nilfs_store_disk_layout(struct the_nilfs *nilfs,
 	nilfs->ns_first_data_block = le64_to_cpu(sbp->s_first_data_block);
 	nilfs->ns_r_segments_percentage =
 		le32_to_cpu(sbp->s_r_segments_percentage);
+	if (nilfs->ns_r_segments_percentage < 1 ||
+	    nilfs->ns_r_segments_percentage > 99) {
+		printk(KERN_ERR "NILFS: invalid reserved segments percentage.\n");
+		return -EINVAL;
+	}
+
 	nilfs_set_nsegments(nilfs, le64_to_cpu(sbp->s_nsegments));
 	nilfs->ns_crc_seed = le32_to_cpu(sbp->s_crc_seed);
 	return 0;
@@ -515,6 +521,7 @@ static int nilfs_load_super_block(struct the_nilfs *nilfs,
 		brelse(sbh[1]);
 		sbh[1] = NULL;
 		sbp[1] = NULL;
+		valid[1] = 0;
 		swp = 0;
 	}
 	if (!valid[swp]) {