Merge tag 'block-5.10-2020-11-20' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:

 - NVMe pull request from Christoph:
      - Doorbell Buffer freeing fix (Minwoo Im)
      - CSE log leak fix (Keith Busch)

 - blk-cgroup hd_struct leak fix (Christoph)

 - Flush request state fix (Ming)

 - dasd NULL deref fix (Stefan)

* tag 'block-5.10-2020-11-20' of git://git.kernel.dk/linux-block:
  s390/dasd: fix null pointer dereference for ERP requests
  blk-cgroup: fix a hd_struct leak in blkcg_fill_root_iostats
  nvme: fix memory leak freeing command effects
  nvme: directly cache command effects log
  nvme: free sq/cq dbbuf pointers when dbbuf set fails
  block: mark flush request as IDLE when it is really finished

Author: torvalds

block/blk-cgroup.c

@@ -849,6 +849,7 @@ static void blkcg_fill_root_iostats(void)
 			blkg_iostat_set(&blkg->iostat.cur, &tmp);
 			u64_stats_update_end(&blkg->iostat.sync);
 		}
+		disk_put_part(part);
 	}
 }
 

block/blk-flush.c

@@ -225,13 +225,18 @@ static void flush_end_io(struct request *flush_rq, blk_status_t error)
 	/* release the tag's ownership to the req cloned from */
 	spin_lock_irqsave(&fq->mq_flush_lock, flags);
 
-	WRITE_ONCE(flush_rq->state, MQ_RQ_IDLE);
 	if (!refcount_dec_and_test(&flush_rq->ref)) {
 		fq->rq_status = error;
 		spin_unlock_irqrestore(&fq->mq_flush_lock, flags);
 		return;
 	}
 
+	/*
+	 * Flush request has to be marked as IDLE when it is really ended
+	 * because its .end_io() is called from timeout code path too for
+	 * avoiding use-after-free.
+	 */
+	WRITE_ONCE(flush_rq->state, MQ_RQ_IDLE);
 	if (fq->rq_status != BLK_STS_OK)
 		error = fq->rq_status;
 

drivers/nvme/host/core.c

@@ -2929,7 +2929,7 @@ int nvme_get_log(struct nvme_ctrl *ctrl, u32 nsid, u8 log_page, u8 lsp, u8 csi,
 static int nvme_get_effects_log(struct nvme_ctrl *ctrl, u8 csi,
 				struct nvme_effects_log **log)
 {
-	struct nvme_cel *cel = xa_load(&ctrl->cels, csi);
+	struct nvme_effects_log	*cel = xa_load(&ctrl->cels, csi);
 	int ret;
 
 	if (cel)
@@ -2940,16 +2940,15 @@ static int nvme_get_effects_log(struct nvme_ctrl *ctrl, u8 csi,
 		return -ENOMEM;
 
 	ret = nvme_get_log(ctrl, 0x00, NVME_LOG_CMD_EFFECTS, 0, csi,
-			&cel->log, sizeof(cel->log), 0);
+			cel, sizeof(*cel), 0);
 	if (ret) {
 		kfree(cel);
 		return ret;
 	}
 
-	cel->csi = csi;
-	xa_store(&ctrl->cels, cel->csi, cel, GFP_KERNEL);
+	xa_store(&ctrl->cels, csi, cel, GFP_KERNEL);
 out:
-	*log = &cel->log;
+	*log = cel;
 	return 0;
 }
 
@@ -4374,6 +4373,19 @@ void nvme_uninit_ctrl(struct nvme_ctrl *ctrl)
 }
 EXPORT_SYMBOL_GPL(nvme_uninit_ctrl);
 
+static void nvme_free_cels(struct nvme_ctrl *ctrl)
+{
+	struct nvme_effects_log	*cel;
+	unsigned long i;
+
+	xa_for_each (&ctrl->cels, i, cel) {
+		xa_erase(&ctrl->cels, i);
+		kfree(cel);
+	}
+
+	xa_destroy(&ctrl->cels);
+}
+
 static void nvme_free_ctrl(struct device *dev)
 {
 	struct nvme_ctrl *ctrl =
@@ -4383,8 +4395,7 @@ static void nvme_free_ctrl(struct device *dev)
 	if (!subsys || ctrl->instance != subsys->instance)
 		ida_simple_remove(&nvme_instance_ida, ctrl->instance);
 
-	xa_destroy(&ctrl->cels);
-
+	nvme_free_cels(ctrl);
 	nvme_mpath_uninit(ctrl);
 	__free_page(ctrl->discard_page);
 

drivers/nvme/host/nvme.h

@@ -226,12 +226,6 @@ struct nvme_fault_inject {
 #endif
 };
 
-struct nvme_cel {
-	struct list_head	entry;
-	struct nvme_effects_log	log;
-	u8			csi;
-};
-
 struct nvme_ctrl {
 	bool comp_seen;
 	enum nvme_ctrl_state state;

drivers/nvme/host/pci.c

@@ -292,9 +292,21 @@ static void nvme_dbbuf_init(struct nvme_dev *dev,
 	nvmeq->dbbuf_cq_ei = &dev->dbbuf_eis[cq_idx(qid, dev->db_stride)];
 }
 
+static void nvme_dbbuf_free(struct nvme_queue *nvmeq)
+{
+	if (!nvmeq->qid)
+		return;
+
+	nvmeq->dbbuf_sq_db = NULL;
+	nvmeq->dbbuf_cq_db = NULL;
+	nvmeq->dbbuf_sq_ei = NULL;
+	nvmeq->dbbuf_cq_ei = NULL;
+}
+
 static void nvme_dbbuf_set(struct nvme_dev *dev)
 {
 	struct nvme_command c;
+	unsigned int i;
 
 	if (!dev->dbbuf_dbs)
 		return;
@@ -308,6 +320,9 @@ static void nvme_dbbuf_set(struct nvme_dev *dev)
 		dev_warn(dev->ctrl.device, "unable to set dbbuf\n");
 		/* Free memory and continue on */
 		nvme_dbbuf_dma_free(dev);
+
+		for (i = 1; i <= dev->online_queues; i++)
+			nvme_dbbuf_free(&dev->queues[i]);
 	}
 }
 

drivers/s390/block/dasd.c

@@ -2980,6 +2980,12 @@ static int _dasd_requeue_request(struct dasd_ccw_req *cqr)
 
 	if (!block)
 		return -EINVAL;
+	/*
+	 * If the request is an ERP request there is nothing to requeue.
+	 * This will be done with the remaining original request.
+	 */
+	if (cqr->refers)
+		return 0;
 	spin_lock_irq(&cqr->dq->lock);
 	req = (struct request *) cqr->callback_data;
 	blk_mq_requeue_request(req, false);