diff options
| -rwxr-xr-x | pkg/sentry/socket/netlink/netlink_state_autogen.go | 2 | ||||
| -rw-r--r-- | pkg/sentry/socket/netlink/provider.go | 7 | ||||
| -rw-r--r-- | pkg/sentry/socket/netlink/route/protocol.go | 5 | ||||
| -rw-r--r-- | pkg/sentry/socket/netlink/socket.go | 42 | ||||
| -rwxr-xr-x | pkg/sentry/socket/netlink/uevent/protocol.go | 60 | ||||
| -rwxr-xr-x | pkg/sentry/socket/netlink/uevent/uevent_state_autogen.go | 20 | ||||
| -rw-r--r-- | runsc/boot/loader.go | 1 |
7 files changed, 137 insertions, 0 deletions
diff --git a/pkg/sentry/socket/netlink/netlink_state_autogen.go b/pkg/sentry/socket/netlink/netlink_state_autogen.go index fa1feb447..39079575e 100755 --- a/pkg/sentry/socket/netlink/netlink_state_autogen.go +++ b/pkg/sentry/socket/netlink/netlink_state_autogen.go @@ -19,6 +19,7 @@ func (x *Socket) save(m state.Map) { m.Save("portID", &x.portID) m.Save("sendBufferSize", &x.sendBufferSize) m.Save("passcred", &x.passcred) + m.Save("filter", &x.filter) } func (x *Socket) afterLoad() {} @@ -33,6 +34,7 @@ func (x *Socket) load(m state.Map) { m.Load("portID", &x.portID) m.Load("sendBufferSize", &x.sendBufferSize) m.Load("passcred", &x.passcred) + m.Load("filter", &x.filter) } func (x *kernelSCM) beforeSave() {} diff --git a/pkg/sentry/socket/netlink/provider.go b/pkg/sentry/socket/netlink/provider.go index 689cad997..be005df24 100644 --- a/pkg/sentry/socket/netlink/provider.go +++ b/pkg/sentry/socket/netlink/provider.go @@ -30,6 +30,13 @@ type Protocol interface { // Protocol returns the Linux netlink protocol value. Protocol() int + // CanSend returns true if this protocol may ever send messages. + // + // TODO(gvisor.dev/issue/1119): This is a workaround to allow + // advertising support for otherwise unimplemented features on sockets + // that will never send messages, thus making those features no-ops. + CanSend() bool + // ProcessMessage processes a single message from userspace. // // If err == nil, any messages added to ms will be sent back to the diff --git a/pkg/sentry/socket/netlink/route/protocol.go b/pkg/sentry/socket/netlink/route/protocol.go index cc70ac237..6b4a0ecf4 100644 --- a/pkg/sentry/socket/netlink/route/protocol.go +++ b/pkg/sentry/socket/netlink/route/protocol.go @@ -61,6 +61,11 @@ func (p *Protocol) Protocol() int { return linux.NETLINK_ROUTE } +// CanSend implements netlink.Protocol.CanSend. +func (p *Protocol) CanSend() bool { + return true +} + // dumpLinks handles RTM_GETLINK + NLM_F_DUMP requests. func (p *Protocol) dumpLinks(ctx context.Context, hdr linux.NetlinkMessageHeader, data []byte, ms *netlink.MessageSet) *syserr.Error { // NLM_F_DUMP + RTM_GETLINK messages are supposed to include an diff --git a/pkg/sentry/socket/netlink/socket.go b/pkg/sentry/socket/netlink/socket.go index 05dac4f0a..4a1b87a9a 100644 --- a/pkg/sentry/socket/netlink/socket.go +++ b/pkg/sentry/socket/netlink/socket.go @@ -54,6 +54,8 @@ const ( maxSendBufferSize = 4 << 20 // 4MB ) +var errNoFilter = syserr.New("no filter attached", linux.ENOENT) + // netlinkSocketDevice is the netlink socket virtual device. var netlinkSocketDevice = device.NewAnonDevice() @@ -108,6 +110,12 @@ type Socket struct { // passcred indicates if this socket wants SCM credentials. passcred bool + + // filter indicates that this socket has a BPF filter "installed". + // + // TODO(gvisor.dev/issue/1119): We don't actually support filtering, + // this is just bookkeeping for tracking add/remove. + filter bool } var _ socket.Socket = (*Socket)(nil) @@ -400,6 +408,40 @@ func (s *Socket) SetSockOpt(t *kernel.Task, level int, name int, opt []byte) *sy s.mu.Unlock() return nil + case linux.SO_ATTACH_FILTER: + // TODO(gvisor.dev/issue/1119): We don't actually + // support filtering. If this socket can't ever send + // messages, then there is nothing to filter and we can + // advertise support. Otherwise, be conservative and + // return an error. + if s.protocol.CanSend() { + socket.SetSockOptEmitUnimplementedEvent(t, name) + return syserr.ErrProtocolNotAvailable + } + + s.mu.Lock() + s.filter = true + s.mu.Unlock() + return nil + + case linux.SO_DETACH_FILTER: + // TODO(gvisor.dev/issue/1119): See above. + if s.protocol.CanSend() { + socket.SetSockOptEmitUnimplementedEvent(t, name) + return syserr.ErrProtocolNotAvailable + } + + s.mu.Lock() + filter := s.filter + s.filter = false + s.mu.Unlock() + + if !filter { + return errNoFilter + } + + return nil + default: socket.SetSockOptEmitUnimplementedEvent(t, name) } diff --git a/pkg/sentry/socket/netlink/uevent/protocol.go b/pkg/sentry/socket/netlink/uevent/protocol.go new file mode 100755 index 000000000..b5d7808d7 --- /dev/null +++ b/pkg/sentry/socket/netlink/uevent/protocol.go @@ -0,0 +1,60 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package uevent provides a NETLINK_KOBJECT_UEVENT socket protocol. +// +// NETLINK_KOBJECT_UEVENT sockets send udev-style device events. gVisor does +// not support any device events, so these sockets never send any messages. +package uevent + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/socket/netlink" + "gvisor.dev/gvisor/pkg/syserr" +) + +// Protocol implements netlink.Protocol. +// +// +stateify savable +type Protocol struct{} + +var _ netlink.Protocol = (*Protocol)(nil) + +// NewProtocol creates a NETLINK_KOBJECT_UEVENT netlink.Protocol. +func NewProtocol(t *kernel.Task) (netlink.Protocol, *syserr.Error) { + return &Protocol{}, nil +} + +// Protocol implements netlink.Protocol.Protocol. +func (p *Protocol) Protocol() int { + return linux.NETLINK_KOBJECT_UEVENT +} + +// CanSend implements netlink.Protocol.CanSend. +func (p *Protocol) CanSend() bool { + return false +} + +// ProcessMessage implements netlink.Protocol.ProcessMessage. +func (p *Protocol) ProcessMessage(ctx context.Context, hdr linux.NetlinkMessageHeader, data []byte, ms *netlink.MessageSet) *syserr.Error { + // Silently ignore all messages. + return nil +} + +// init registers the NETLINK_KOBJECT_UEVENT provider. +func init() { + netlink.RegisterProvider(linux.NETLINK_KOBJECT_UEVENT, NewProtocol) +} diff --git a/pkg/sentry/socket/netlink/uevent/uevent_state_autogen.go b/pkg/sentry/socket/netlink/uevent/uevent_state_autogen.go new file mode 100755 index 000000000..01a99399d --- /dev/null +++ b/pkg/sentry/socket/netlink/uevent/uevent_state_autogen.go @@ -0,0 +1,20 @@ +// automatically generated by stateify. + +package uevent + +import ( + "gvisor.dev/gvisor/pkg/state" +) + +func (x *Protocol) beforeSave() {} +func (x *Protocol) save(m state.Map) { + x.beforeSave() +} + +func (x *Protocol) afterLoad() {} +func (x *Protocol) load(m state.Map) { +} + +func init() { + state.Register("uevent.Protocol", (*Protocol)(nil), state.Fns{Save: (*Protocol).save, Load: (*Protocol).load}) +} diff --git a/runsc/boot/loader.go b/runsc/boot/loader.go index 4d1bd2d08..f05d5973f 100644 --- a/runsc/boot/loader.go +++ b/runsc/boot/loader.go @@ -65,6 +65,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/socket/hostinet" _ "gvisor.dev/gvisor/pkg/sentry/socket/netlink" _ "gvisor.dev/gvisor/pkg/sentry/socket/netlink/route" + _ "gvisor.dev/gvisor/pkg/sentry/socket/netlink/uevent" "gvisor.dev/gvisor/pkg/sentry/socket/netstack" _ "gvisor.dev/gvisor/pkg/sentry/socket/unix" ) |