From 17e6be412054ae22027a339614fca82d55e64973 Mon Sep 17 00:00:00 2001
From: qihao <qihao@cmss.chinamobile.com>
Date: Thu, 30 Mar 2023 17:45:11 +0800
Subject: [PATCH] vhost-user-blk: fix the resize crash

cheery-pick from ab6075d849f4285fc730d3ae6e17418d65d09998

If the os is not installed and doesn't have the virtio guest driver,
the vhost dev isn't started, so the dev->vdev is NULL.

Reproduce: mount a Win 2019 iso, go into the install ui, then resize
the virtio-blk device, qemu crash.

Signed-off-by: qihao_yewu <qihao_yewu@cmss.chinamobile.com>
Signed-off-by: Li Feng <fengli@smartx.com>
Message-Id: <20220919121816.3252223-1-fengli@smartx.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 hw/block/vhost-user-blk.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c
index eb1264afc7..bcc3f83c4b 100644
--- a/hw/block/vhost-user-blk.c
+++ b/hw/block/vhost-user-blk.c
@@ -95,6 +95,10 @@ static int vhost_user_blk_handle_config_change(struct vhost_dev *dev)
     VHostUserBlk *s = VHOST_USER_BLK(dev->vdev);
     Error *local_err = NULL;
 
+    if (!dev->started) {
+        return 0;
+    }
+
     ret = vhost_dev_get_config(dev, (uint8_t *)&blkcfg,
                                sizeof(struct virtio_blk_config),
                                &local_err);
-- 
2.27.0