[PATCH v4 8/8] vhost_scsi: Add check for inherit_owner status

[Cindy Lu]

The vhost_scsi VHOST_NEW_WORKER requires the inherit_owner
setting to be true. So we need to implement a check for this.

Signed-off-by: Cindy Lu <l...@redhat.com>
---
 drivers/vhost/scsi.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index 718fa4e0b31e..0d63b6b5c852 100644
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -2086,6 +2086,14 @@ vhost_scsi_ioctl(struct file *f,
                        return -EFAULT;
                return vhost_scsi_set_features(vs, features);
        case VHOST_NEW_WORKER:
+               /*
+                * vhost_tasks will account for worker threads under the 
parent's
+                * NPROC value but kthreads do not. To avoid userspace 
overflowing
+                * the system with worker threads inherit_owner must be true.
+                */
+               if (!vs->dev.inherit_owner)
+                       return -EFAULT;
+               fallthrough;
        case VHOST_FREE_WORKER:
        case VHOST_ATTACH_VRING_WORKER:
        case VHOST_GET_VRING_WORKER:
-- 
2.45.0