Merge tag 'block-5.15-2021-10-09' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Two small fixes for this release:

   - Add missing QUEUE_FLAG_HCTX_ACTIVE in the debugfs handling
     (Johannes)

   - Fix double free / UAF issue in __alloc_disk_node (Tetsuo)"

* tag 'block-5.15-2021-10-09' of git://git.kernel.dk/linux-block:
  block: decode QUEUE_FLAG_HCTX_ACTIVE in debugfs output
  block: genhd: fix double kfree() in __alloc_disk_node()

block/bdev.c

@@ -490,7 +490,6 @@ struct block_device *bdev_alloc(struct gendisk *disk, u8 partno)
 	bdev = I_BDEV(inode);
 	mutex_init(&bdev->bd_fsfreeze_mutex);
 	spin_lock_init(&bdev->bd_size_lock);
-	bdev->bd_disk = disk;
 	bdev->bd_partno = partno;
 	bdev->bd_inode = inode;
 	bdev->bd_stats = alloc_percpu(struct disk_stats);
@@ -498,6 +497,7 @@ struct block_device *bdev_alloc(struct gendisk *disk, u8 partno)
 		iput(inode);
 		return NULL;
 	}
+	bdev->bd_disk = disk;
 	return bdev;
 }
 

block/blk-mq-debugfs.c

@@ -129,6 +129,7 @@ static const char *const blk_queue_flag_name[] = {
 	QUEUE_FLAG_NAME(PCI_P2PDMA),
 	QUEUE_FLAG_NAME(ZONE_RESETALL),
 	QUEUE_FLAG_NAME(RQ_ALLOC_TIME),
+	QUEUE_FLAG_NAME(HCTX_ACTIVE),
 	QUEUE_FLAG_NAME(NOWAIT),
 };
 #undef QUEUE_FLAG_NAME

block/genhd.c

@@ -1268,6 +1268,7 @@ struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id,
 
 out_destroy_part_tbl:
 	xa_destroy(&disk->part_tbl);
+	disk->part0->bd_disk = NULL;
 	iput(disk->part0->bd_inode);
 out_free_bdi:
 	bdi_put(disk->bdi);