From ebdede644bbf5744f91dbe0d39742f17b03c4e10 Mon Sep 17 00:00:00 2001 From: Stefano Garzarella Date: Tue, 18 Jun 2024 12:00:34 +0200 Subject: libvhost-user: mask F_INFLIGHT_SHMFD if memfd is not supported MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Tested-by: Philippe Mathieu-Daudé Acked-by: Stefan Hajnoczi Reviewed-by: David Hildenbrand Signed-off-by: Stefano Garzarella Message-Id: <20240618100043.144657-5-sgarzare@redhat.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- subprojects/libvhost-user/libvhost-user.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'subprojects') diff --git a/subprojects/libvhost-user/libvhost-user.c b/subprojects/libvhost-user/libvhost-user.c index ea27683dac..9c630c2170 100644 --- a/subprojects/libvhost-user/libvhost-user.c +++ b/subprojects/libvhost-user/libvhost-user.c @@ -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; } -- cgit v1.2.3