1 files changed, 21 insertions, 23 deletions

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index b47b2a87ae8f..5a1f98494ddd 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -260,7 +260,7 @@ static void nbd_dev_remove(struct nbd_device *nbd)
 	mutex_lock(&nbd_index_mutex);
 	idr_remove(&nbd_index_idr, nbd->index);
 	mutex_unlock(&nbd_index_mutex);
-
+	destroy_workqueue(nbd->recv_workq);
 	kfree(nbd);
 }
 
@@ -755,6 +755,8 @@ static struct nbd_cmd *nbd_handle_reply(struct nbd_device *nbd, int index,
 	if (cmd->index != index) {
 		dev_err(disk_to_dev(nbd->disk), "Unexpected reply %d from different sock %d (expected %d)",
 			tag, index, cmd->index);
+		ret = -ENOENT;
+		goto out;
 	}
 	if (cmd->cmd_cookie != nbd_handle_to_cookie(handle)) {
 		dev_err(disk_to_dev(nbd->disk), "Double reply on req %p, cmd_cookie %u, handle cookie %u\n",
@@ -1314,10 +1316,6 @@ static void nbd_config_put(struct nbd_device *nbd)
 		kfree(nbd->config);
 		nbd->config = NULL;
 
-		if (nbd->recv_workq)
-			destroy_workqueue(nbd->recv_workq);
-		nbd->recv_workq = NULL;
-
 		nbd->tag_set.timeout = 0;
 		nbd->disk->queue->limits.discard_granularity = 0;
 		nbd->disk->queue->limits.discard_alignment = 0;
@@ -1346,14 +1344,6 @@ static int nbd_start_device(struct nbd_device *nbd)
 		return -EINVAL;
 	}
 
-	nbd->recv_workq = alloc_workqueue("knbd%d-recv",
-					  WQ_MEM_RECLAIM | WQ_HIGHPRI |
-					  WQ_UNBOUND, 0, nbd->index);
-	if (!nbd->recv_workq) {
-		dev_err(disk_to_dev(nbd->disk), "Could not allocate knbd recv work queue.\n");
-		return -ENOMEM;
-	}
-
 	blk_mq_update_nr_hw_queues(&nbd->tag_set, config->num_connections);
 	nbd->pid = task_pid_nr(current);
 
@@ -1779,6 +1769,15 @@ static struct nbd_device *nbd_dev_add(int index, unsigned int refs)
 	}
 	nbd->disk = disk;
 
+	nbd->recv_workq = alloc_workqueue("nbd%d-recv",
+					  WQ_MEM_RECLAIM | WQ_HIGHPRI |
+					  WQ_UNBOUND, 0, nbd->index);
+	if (!nbd->recv_workq) {
+		dev_err(disk_to_dev(nbd->disk), "Could not allocate knbd recv work queue.\n");
+		err = -ENOMEM;
+		goto out_err_disk;
+	}
+
 	/*
 	 * Tell the block layer that we are not a rotational device
 	 */
@@ -1803,13 +1802,13 @@ static struct nbd_device *nbd_dev_add(int index, unsigned int refs)
 	disk->major = NBD_MAJOR;
 
 	/* Too big first_minor can cause duplicate creation of
-	 * sysfs files/links, since first_minor will be truncated to
-	 * byte in __device_add_disk().
+	 * sysfs files/links, since index << part_shift might overflow, or
+	 * MKDEV() expect that the max bits of first_minor is 20.
 	 */
 	disk->first_minor = index << part_shift;
-	if (disk->first_minor > 0xff) {
+	if (disk->first_minor < index || disk->first_minor > MINORMASK) {
 		err = -EINVAL;
-		goto out_free_idr;
+		goto out_free_work;
 	}
 
 	disk->minors = 1 << part_shift;
@@ -1818,7 +1817,7 @@ static struct nbd_device *nbd_dev_add(int index, unsigned int refs)
 	sprintf(disk->disk_name, "nbd%d", index);
 	err = add_disk(disk);
 	if (err)
-		goto out_err_disk;
+		goto out_free_work;
 
 	/*
 	 * Now publish the device.
@@ -1827,6 +1826,8 @@ static struct nbd_device *nbd_dev_add(int index, unsigned int refs)
 	nbd_total_devices++;
 	return nbd;
 
+out_free_work:
+	destroy_workqueue(nbd->recv_workq);
 out_err_disk:
 	blk_cleanup_disk(disk);
 out_free_idr:
@@ -2082,13 +2083,10 @@ static void nbd_disconnect_and_put(struct nbd_device *nbd)
 	nbd_disconnect(nbd);
 	sock_shutdown(nbd);
 	/*
-	 * Make sure recv thread has finished, so it does not drop the last
-	 * config ref and try to destroy the workqueue from inside the work
-	 * queue. And this also ensure that we can safely call nbd_clear_que()
+	 * Make sure recv thread has finished, we can safely call nbd_clear_que()
 	 * to cancel the inflight I/Os.
 	 */
-	if (nbd->recv_workq)
-		flush_workqueue(nbd->recv_workq);
+	flush_workqueue(nbd->recv_workq);
 	nbd_clear_que(nbd);
 	nbd->task_setup = NULL;
 	mutex_unlock(&nbd->config_lock);