Re: [PATCH net] vsock: forward all packets to the host when no H2G is registered
On Thu, Nov 19, 2020 at 03:25:42PM +0100, Alexander Graf wrote: On 19.11.20 15:03, Stefan Hajnoczi wrote: On Thu, Nov 12, 2020 at 02:38:37PM +0100, Stefano Garzarella wrote: Before commit c0cfa2d8a788 ("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 Cc: Dexuan Cui Fixes: c0cfa2d8a788 ("vsock: add multi-transports support") Reported-by: Andra Paraschiv Tested-by: Andra Paraschiv Signed-off-by: Stefano Garzarella --- net/vmw_vsock/af_vsock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Acked-by: Stefan Hajnoczi Is there anything we have to do to also get this into the affected stable trees? :) The patch is already queued by Jakub in the netdev stable queue: https://patchwork.kernel.org/bundle/netdev/stable/?series=382773=* Stefano
Re: [PATCH net] vsock: forward all packets to the host when no H2G is registered
On 19.11.20 15:03, Stefan Hajnoczi wrote: On Thu, Nov 12, 2020 at 02:38:37PM +0100, Stefano Garzarella wrote: Before commit c0cfa2d8a788 ("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 Cc: Dexuan Cui Fixes: c0cfa2d8a788 ("vsock: add multi-transports support") Reported-by: Andra Paraschiv Tested-by: Andra Paraschiv Signed-off-by: Stefano Garzarella --- net/vmw_vsock/af_vsock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Acked-by: Stefan Hajnoczi Is there anything we have to do to also get this into the affected stable trees? :) Alex Amazon Development Center Germany GmbH Krausenstr. 38 10117 Berlin Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B Sitz: Berlin Ust-ID: DE 289 237 879
Re: [PATCH net] vsock: forward all packets to the host when no H2G is registered
On Thu, Nov 12, 2020 at 02:38:37PM +0100, Stefano Garzarella wrote: > Before commit c0cfa2d8a788 ("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 > Cc: Dexuan Cui > Fixes: c0cfa2d8a788 ("vsock: add multi-transports support") > Reported-by: Andra Paraschiv > Tested-by: Andra Paraschiv > Signed-off-by: Stefano Garzarella > --- > net/vmw_vsock/af_vsock.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) Acked-by: Stefan Hajnoczi signature.asc Description: PGP signature
Re: [PATCH net] vsock: forward all packets to the host when no H2G is registered
Hello: This patch was applied to netdev/net.git (refs/heads/master): On Thu, 12 Nov 2020 14:38:37 +0100 you wrote: > Before commit c0cfa2d8a788 ("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. > > [...] Here is the summary with links: - [net] vsock: forward all packets to the host when no H2G is registered https://git.kernel.org/netdev/net/c/65b422d9b61b You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
[PATCH net] vsock: forward all packets to the host when no H2G is registered
Before commit c0cfa2d8a788 ("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 Cc: Dexuan Cui Fixes: c0cfa2d8a788 ("vsock: add multi-transports support") Reported-by: Andra Paraschiv Tested-by: Andra Paraschiv Signed-off-by: Stefano Garzarella --- net/vmw_vsock/af_vsock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index b4d7b8aba003..d10916ab4526 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -438,7 +438,7 @@ int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk) case SOCK_STREAM: if (vsock_use_local_transport(remote_cid)) new_transport = transport_local; - else if (remote_cid <= VMADDR_CID_HOST) + else if (remote_cid <= VMADDR_CID_HOST || !transport_h2g) new_transport = transport_g2h; else new_transport = transport_h2g; -- 2.26.2