From 3517ac4c0bcd54222e7c72b1497ad1f946e2d08e Mon Sep 17 00:00:00 2001
From: Tony Gong <gongt@google.com>
Date: Tue, 5 Dec 2023 10:18:49 -0800
Subject: [PATCH] Cancel multicast delayed report job on Disable

Cancel the delayed report job when operating in V2 mode (this already
happens in V1 mode) in MakeAllNonMemberLocked, which is called on
endpoint Disable. This prevents a panic inside the delayed report
job where it asserts that the protocol is enabled.

PiperOrigin-RevId: 588113303
---
 .../internal/ip/generic_multicast_protocol.go |   4 +-
 .../ip/generic_multicast_protocol_test.go     | 101 ++++++++++++++++++
 2 files changed, 104 insertions(+), 1 deletion(-)

diff --git a/pkg/tcpip/network/internal/ip/generic_multicast_protocol.go b/pkg/tcpip/network/internal/ip/generic_multicast_protocol.go
index 884ea0562c..54c38b83be 100644
--- a/pkg/tcpip/network/internal/ip/generic_multicast_protocol.go
+++ b/pkg/tcpip/network/internal/ip/generic_multicast_protocol.go
@@ -390,7 +390,9 @@ func (g *GenericMulticastProtocolState) MakeAllNonMemberLocked() {
 	switch g.mode {
 	case protocolModeV2:
 		v2ReportBuilder = g.opts.Protocol.NewReportV2Builder()
-		handler = func(groupAddress tcpip.Address, _ *multicastGroupState) {
+		handler = func(groupAddress tcpip.Address, info *multicastGroupState) {
+			info.cancelDelayedReportJob()
+
 			// Send a report immediately to announce us leaving the group.
 			v2ReportBuilder.AddRecord(
 				MulticastGroupProtocolV2ReportRecordChangeToIncludeMode,
diff --git a/pkg/tcpip/network/internal/ip/generic_multicast_protocol_test.go b/pkg/tcpip/network/internal/ip/generic_multicast_protocol_test.go
index 8f1a2e446f..6e1ff80b3a 100644
--- a/pkg/tcpip/network/internal/ip/generic_multicast_protocol_test.go
+++ b/pkg/tcpip/network/internal/ip/generic_multicast_protocol_test.go
@@ -1392,6 +1392,107 @@ func TestGroupStateNonMember(t *testing.T) {
 	}
 }
 
+// TestMakeAllNonMemberCancelsDelayedReportJob tests that the delayed report job
+// is cancelled on MakeAllNonMember, otherwise the job will panic if the endpoint
+// is disabled.
+func TestMakeAllNonMemberCancelsDelayedReportJob(t *testing.T) {
+	const maxRespCode = 1
+
+	tests := []struct {
+		name            string
+		v1              bool
+		v1Compatibility bool
+		checkFields     func(tcpip.Address, bool) checkFields
+	}{
+		{
+			name:            "V1",
+			v1:              true,
+			v1Compatibility: false,
+			checkFields: func(addr tcpip.Address, leave bool) checkFields {
+				if leave {
+					return checkFields{sendLeaveGroupAddresses: []tcpip.Address{addr}}
+				}
+				return checkFields{sendReportGroupAddresses: []tcpip.Address{addr}}
+			},
+		},
+		{
+			name:            "V1 Compatibility",
+			v1:              false,
+			v1Compatibility: true,
+			checkFields: func(addr tcpip.Address, leave bool) checkFields {
+				if leave {
+					return checkFields{sendLeaveGroupAddresses: []tcpip.Address{addr}}
+				}
+				return checkFields{sendReportGroupAddresses: []tcpip.Address{addr}}
+			},
+		},
+		{
+			name:            "V2",
+			v1:              false,
+			v1Compatibility: false,
+			checkFields: func(addr tcpip.Address, leave bool) checkFields {
+				recordType := ip.MulticastGroupProtocolV2ReportRecordChangeToExcludeMode
+				if leave {
+					recordType = ip.MulticastGroupProtocolV2ReportRecordChangeToIncludeMode
+				}
+				return checkFields{sentV2Reports: []mockReportV2{{records: []mockReportV2Record{mockReportV2Record{
+					recordType:   recordType,
+					groupAddress: addr,
+				}}}}}
+			},
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			mgp := mockMulticastGroupProtocol{t: t}
+			clock := faketime.NewManualClock()
+
+			mgp.init(ip.GenericMulticastProtocolOptions{
+				Rand:                      rand.New(rand.NewSource(3)),
+				Clock:                     clock,
+				MaxUnsolicitedReportDelay: maxUnsolicitedReportDelay,
+			}, test.v1)
+
+			if test.v1Compatibility {
+				// V1 query targeting an unjoined group should drop us into V1
+				// compatibility mode without sending any packets, affecting tests.
+				mgp.handleQuery(addr3, 0)
+			}
+
+			mgp.joinGroup(addr1)
+			if diff := mgp.check(test.checkFields(addr1, false /* leave */)); diff != "" {
+				t.Fatalf("mockMulticastGroupProtocol mismatch (-want +got):\n%s", diff)
+			}
+
+			// Handle a query so that the delayed report job is scheduled when operating
+			// in V2 mode.
+			mgp.handleQueryV2(addr1, maxRespCode, header.MakeAddressIterator(addr1.Len(), bytes.NewBuffer(nil)), 0, 0)
+
+			mgp.makeAllNonMember()
+			if diff := mgp.check(test.checkFields(addr1, true /* leave */)); diff != "" {
+				t.Errorf("mockMulticastGroupProtocol mismatch (-want +got):\n%s", diff)
+			}
+
+			mgp.setEnabled(false)
+
+			// Generic multicast protocol timers are expected to take the job mutex.
+			//
+			// Advance the clock to after the delayed report job is supposed to fire.
+			// If the delayed report job isn't cancelled by the MakeAllNonMember call,
+			// it will panic due to the expectation that the protocol is enabled.
+			if test.v1 || test.v1Compatibility {
+				clock.Advance(mgp.V2QueryMaxRespCodeToV1Delay(maxRespCode))
+			} else {
+				clock.Advance(mgp.V2QueryMaxRespCodeToV2Delay(maxRespCode))
+			}
+			if diff := mgp.check(checkFields{}); diff != "" {
+				t.Errorf("mockMulticastGroupProtocol mismatch (-want +got):\n%s", diff)
+			}
+		})
+	}
+}
+
 func TestQueuedPackets(t *testing.T) {
 	tests := []struct {
 		name            string