tests: Reproduce issue 14685

Signed-off-by: Marek Siarkowicz <siarkowicz@google.com>

Makefile

@@ -129,6 +129,27 @@ gofail-disable: install-gofail
 install-gofail:
 	cd tools/mod; go install go.etcd.io/gofail@${GOFAIL_VERSION}
 
+# Reproduce historical issues
+
+.PHONY: reproduce-issue14685
+reproduce-issue14685: ./bin/etcd-v3.5.5-failpoints
+	cp ./bin/etcd-v3.5.5-failpoints ./bin/etcd
+	GO_TEST_FLAGS='-v --run=TestLinearizability/Issue14685 --count 100 --failfast' make test-linearizability
+
+./bin/etcd-v3.5.5-failpoints:
+	rm -rf /tmp/etcd-release-v3.5.5/
+	mkdir -p /tmp/etcd-release-v3.5.5/
+	cd /tmp/etcd-release-v3.5.5/; \
+	  git clone https://github.com/etcd-io/etcd.git .; \
+	  git checkout v3.5.5; \
+	  go get go.etcd.io/gofail@${GOFAIL_VERSION}; \
+	  (cd server; go get go.etcd.io/gofail@${GOFAIL_VERSION}); \
+	  (cd etcdctl; go get go.etcd.io/gofail@${GOFAIL_VERSION}); \
+	  (cd etcdutl; go get go.etcd.io/gofail@${GOFAIL_VERSION}); \
+	  FAILPOINTS=true ./build;
+	mkdir -p ./bin
+	cp /tmp/etcd-release-v3.5.5/bin/etcd ./bin/etcd-v3.5.5-failpoints
+
 # Cleanup
 
 clean:

tests/linearizability/linearizability_test.go

@@ -70,6 +70,14 @@ func TestLinearizability(t *testing.T) {
 				e2e.WithGoFailEnabled(true),
 			),
 		},
+		{
+			name:      "Issue14685",
+			failpoint: DefragBeforeCopyPanic,
+			config: *e2e.NewConfig(
+				e2e.WithClusterSize(1),
+				e2e.WithGoFailEnabled(true),
+			),
+		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.name, func(t *testing.T) {