libvhost-user: mask F_INFLIGHT_SHMFD if memfd is not supported

libvhost-user will panic when receiving VHOST_USER_GET_INFLIGHT_FD
message if MFD_ALLOW_SEALING is not defined, since it's not able
to create a memfd.

VHOST_USER_GET_INFLIGHT_FD is used only if
VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD is negotiated. So, let's mask
that feature if the backend is not able to properly handle these
messages.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20240618100043.144657-5-sgarzare@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Stefano Garzarella 2024-06-18 12:00:34 +02:00 committed by Michael S. Tsirkin
parent 92b58bc7e9
commit ebdede644b
1 changed files with 11 additions and 0 deletions

View File

@ -1674,6 +1674,17 @@ vu_get_protocol_features_exec(VuDev *dev, VhostUserMsg *vmsg)
features |= dev->iface->get_protocol_features(dev);
}
#ifndef MFD_ALLOW_SEALING
/*
* If MFD_ALLOW_SEALING is not defined, we are not able to handle
* VHOST_USER_GET_INFLIGHT_FD messages, since we can't create a memfd.
* Those messages are used only if VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD
* is negotiated. A device implementation can enable it, so let's mask
* it to avoid a runtime panic.
*/
features &= ~(1ULL << VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD);
#endif
vmsg_set_reply_u64(vmsg, features);
return true;
}