ubi: Free the normal volumes in error paths of ubi_attach_mtd_dev()

The allocated normal volumes saved in ubi->volumes are not freed
in the error paths in ubi_attach_mtd_dev() and its callees (e.g.
ubi_attach() and ubi_read_volume_table()).

These normal volumes should be freed through kill_volumes() and
vol_release(), but ubi_attach_mtd_dev() may fail before
calling uif_init(), and there will be memory leaks.

So adding a new helper ubi_free_all_volumes() to free the normal
and the internal volumes. And in order to prevent double-free
of volume, reset ubi->volumes[i] to NULL after freeing.

Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

1 files changed, 26 insertions, 5 deletions

diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index d636bbe214cb..25fb72b2efa0 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -503,21 +503,42 @@ static void uif_close(struct ubi_device *ubi)
 }
 
 /**
- * ubi_free_internal_volumes - free internal volumes.
+ * ubi_free_volumes_from - free volumes from specific index.
  * @ubi: UBI device description object
+ * @from: the start index used for volume free.
  */
-void ubi_free_internal_volumes(struct ubi_device *ubi)
+static void ubi_free_volumes_from(struct ubi_device *ubi, int from)
 {
 	int i;
 
-	for (i = ubi->vtbl_slots;
-	     i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
+	for (i = from; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
+		if (!ubi->volumes[i])
+			continue;
 		ubi_eba_replace_table(ubi->volumes[i], NULL);
 		ubi_fastmap_destroy_checkmap(ubi->volumes[i]);
 		kfree(ubi->volumes[i]);
+		ubi->volumes[i] = NULL;
 	}
 }
 
+/**
+ * ubi_free_all_volumes - free all volumes.
+ * @ubi: UBI device description object
+ */
+void ubi_free_all_volumes(struct ubi_device *ubi)
+{
+	ubi_free_volumes_from(ubi, 0);
+}
+
+/**
+ * ubi_free_internal_volumes - free internal volumes.
+ * @ubi: UBI device description object
+ */
+void ubi_free_internal_volumes(struct ubi_device *ubi)
+{
+	ubi_free_volumes_from(ubi, ubi->vtbl_slots);
+}
+
 static int get_bad_peb_limit(const struct ubi_device *ubi, int max_beb_per1024)
 {
 	int limit, device_pebs;
@@ -1013,7 +1034,7 @@ out_uif:
 out_detach:
 	ubi_devices[ubi_num] = NULL;
 	ubi_wl_close(ubi);
-	ubi_free_internal_volumes(ubi);
+	ubi_free_all_volumes(ubi);
 	vfree(ubi->vtbl);
 out_free:
 	vfree(ubi->peb_buf);