Headline
CVE-2021-32844: Various fixes by fredericdalleau · Pull Request #313 · moby/hyperkit
HyperKit is a toolkit for embedding hypervisor capabilities in an application. In versions 0.20210107 and prior of HyperKit, vi_pci_write has is a call to vc_cfgwrite that does not check for null which when called makes the host crash. This issue may lead to a guest crashing the host causing a denial of service. This issue is fixed in commit 451558fe8aaa8b24e02e34106e3bb9fe41d7ad13.
This series add some fixes for various cases that have been reported that allow the guest to trigger a crash of the virtual machine.
The first two are NULL pointer dereference and are already handled in bhyve.
https://cgit.freebsd.org/src/tree/usr.sbin/bhyve/virtio.c#n606
https://cgit.freebsd.org/src/tree/usr.sbin/bhyve/virtio.c#n725
The other two are unhandled returned errors in vq_getchain. For now, trace and return as in pci_vt9p_notify.
Let me know what you think.