diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 0994f6a7..58fd707 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -704,7 +704,8 @@
 	sbp[0]->s_state =
 		cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS);
 	/* synchronize sbp[1] with sbp[0] */
-	memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
+	if (sbp[1])
+		memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
 	return nilfs_commit_super(sbi, NILFS_SB_COMMIT_ALL);
 }