virtio/pci: explicit zero unknown devices features
The linux kernel implementation for the virtio_net driver recently
gained support for virtio features above the 64th bit.
It relies on the hypervisor to clear the features data for unknown /
unsupported features range.
The current pci-modern implementation, in such scenario, leaves the
data memory untouched, which causes the guest kernel assuming "random"
features are supported (and possibly leaks host memory contents).
Explicitly clear the features data for unsupported range.
Reported-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/ed62443b8fd3fef87bd313a54f821cf363f647a5.1755185758.git.pabeni@redhat.com
Signed-off-by: Will Deacon <will@kernel.org>
1 file changed
