linux_dsm_epyc7002/net/vmw_vsock
Stefano Garzarella 65b422d9b6 vsock: forward all packets to the host when no H2G is registered
Before commit c0cfa2d8a7 ("vsock: add multi-transports support"),
if a G2H transport was loaded (e.g. virtio transport), every packets
was forwarded to the host, regardless of the destination CID.
The H2G transports implemented until then (vhost-vsock, VMCI) always
responded with an error, if the destination CID was not
VMADDR_CID_HOST.

From that commit, we are using the remote CID to decide which
transport to use, so packets with remote CID > VMADDR_CID_HOST(2)
are sent only through H2G transport. If no H2G is available, packets
are discarded directly in the guest.

Some use cases (e.g. Nitro Enclaves [1]) rely on the old behaviour
to implement sibling VMs communication, so we restore the old
behavior when no H2G is registered.
It will be up to the host to discard packets if the destination is
not the right one. As it was already implemented before adding
multi-transport support.

Tested with nested QEMU/KVM by me and Nitro Enclaves by Andra.

[1] Documentation/virt/ne_overview.rst

Cc: Jorgen Hansen <jhansen@vmware.com>
Cc: Dexuan Cui <decui@microsoft.com>
Fixes: c0cfa2d8a7 ("vsock: add multi-transports support")
Reported-by: Andra Paraschiv <andraprs@amazon.com>
Tested-by: Andra Paraschiv <andraprs@amazon.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20201112133837.34183-1-sgarzare@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-14 11:33:39 -08:00
..
af_vsock_tap.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
af_vsock.c vsock: forward all packets to the host when no H2G is registered 2020-11-14 11:33:39 -08:00
diag.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 321 2019-06-05 17:37:05 +02:00
hyperv_transport.c vsock: fix potential deadlock in transport->release() 2020-02-27 12:03:56 -08:00
Kconfig vsock: add vsock_loopback transport 2019-12-11 15:01:23 -08:00
Makefile vsock: add vsock_loopback transport 2019-12-11 15:01:23 -08:00
virtio_transport_common.c virtio_vsock: Fix race condition in virtio_transport_recv_pkt 2020-05-30 17:44:01 -07:00
virtio_transport.c vsock/virtio: annotate 'the_virtio_vsock' RCU pointer 2020-07-15 17:47:15 -07:00
vmci_transport_notify_qstate.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 321 2019-06-05 17:37:05 +02:00
vmci_transport_notify.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 321 2019-06-05 17:37:05 +02:00
vmci_transport_notify.h vsock: remove include/linux/vm_sockets.h file 2019-11-14 18:12:17 -08:00
vmci_transport.c vsock/vmci: make vmci_vsock_transport_cb() static 2020-06-05 13:18:26 -07:00
vmci_transport.h vsock: handle buffer_size sockopts in the core 2019-11-14 18:12:18 -08:00
vsock_addr.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 321 2019-06-05 17:37:05 +02:00
vsock_loopback.c vsock: add vsock_loopback transport 2019-12-11 15:01:23 -08:00