Fix panic when parsing SO_TIMESTAMP cmsg

PiperOrigin-RevId: 350223482

1 files changed, 59 insertions, 0 deletions

diff --git a/pkg/sentry/socket/control/control_test.go b/pkg/sentry/socket/control/control_test.go
new file mode 100644
index 000000000..d40a4cc85
--- /dev/null
+++ b/pkg/sentry/socket/control/control_test.go
@@ -0,0 +1,59 @@
+// Copyright 2020 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 control provides internal representations of socket control
+// messages.
+package control
+
+import (
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/binary"
+	"gvisor.dev/gvisor/pkg/sentry/socket"
+	"gvisor.dev/gvisor/pkg/usermem"
+)
+
+func TestParse(t *testing.T) {
+	// Craft the control message to parse.
+	length := linux.SizeOfControlMessageHeader + linux.SizeOfTimeval
+	hdr := linux.ControlMessageHeader{
+		Length: uint64(length),
+		Level:  linux.SOL_SOCKET,
+		Type:   linux.SO_TIMESTAMP,
+	}
+	buf := make([]byte, 0, length)
+	buf = binary.Marshal(buf, usermem.ByteOrder, &hdr)
+	ts := linux.Timeval{
+		Sec:  2401,
+		Usec: 343,
+	}
+	buf = binary.Marshal(buf, usermem.ByteOrder, &ts)
+
+	cmsg, err := Parse(nil, nil, buf, 8 /* width */)
+	if err != nil {
+		t.Fatalf("Parse(_, _, %+v, _): %v", cmsg, err)
+	}
+
+	want := socket.ControlMessages{
+		IP: socket.IPControlMessages{
+			HasTimestamp: true,
+			Timestamp:    ts.ToNsecCapped(),
+		},
+	}
+	if diff := cmp.Diff(want, cmsg); diff != "" {
+		t.Errorf("unexpected message parsed, (-want, +got):\n%s", diff)
+	}
+}