Add a BlockDriverState NULL check to virtio_blk_handle_request()
to prevent a segfault if the drive is forcibly removed using HMP
'drive_del' (without performing a hotplug 'device_del' first).
Signed-off-by: Mark Kanda <mark.ka...@oracle.com>
Reviewed-by: Karl Heubaum <karl.heub...@oracle.com>
Reviewed-by: Ameya More <ameya.m...@oracle.com>
---
hw/block/virtio-blk.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
index b1532e4..76ddbbf 100644
--- a/hw/block/virtio-blk.c
+++ b/hw/block/virtio-blk.c
@@ -507,6 +507,13 @@ static int virtio_blk_handle_request(VirtIOBlockReq *req,
MultiReqBuffer *mrb)
return -1;
}
+ /* If the drive was forcibly removed (e.g. HMP 'drive_del'), the block
+ * driver state may be NULL and there is nothing left to do. */
+ if (!blk_bs(req->dev->blk)) {
+ virtio_error(vdev, "virtio-blk BlockDriverState is NULL");
+ return -1;
+ }
+
/* We always touch the last byte, so just see how big in_iov is. */
req->in_len = iov_size(in_iov, in_num);
req->in = (void *)in_iov[in_num - 1].iov_base
--
1.8.3.1
