From e3265bf424e3bf26f2fc4cc25978e880e64c405c Mon Sep 17 00:00:00 2001
From: Quique Llorente <ellorent@redhat.com>
Date: Mon, 1 Feb 2021 15:08:28 +0100
Subject: [PATCH] Skip linux-bridge filtering if no "bridge" section

We have found that at some envs the "bridge" section from linux-bridge
is not present in case the bridge is down, this change ignore the
filtering in this is the case to preveng a segmentation fault.

Signed-off-by: Quique Llorente <ellorent@redhat.com>
---
 pkg/nmstatectl/remote.go | 68 ++++++++++++++++++++++++++++++++++++++++
 pkg/state/filter.go      | 19 +++++++++--
 pkg/state/filter_test.go | 62 ++++++++++++++++++++++++++++++++++++
 3 files changed, 147 insertions(+), 2 deletions(-)
 create mode 100644 pkg/nmstatectl/remote.go

diff --git a/pkg/nmstatectl/remote.go b/pkg/nmstatectl/remote.go
new file mode 100644
index 0000000000..84631d5033
--- /dev/null
+++ b/pkg/nmstatectl/remote.go
@@ -0,0 +1,68 @@
+package nmstatectl
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+
+	v1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/kubernetes/scheme"
+	"k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/remotecommand"
+)
+
+func ShowAtNode(config *rest.Config, nodeName string) (string, error) {
+	cmd := []string{
+		"sh",
+		"-c",
+		"nmstatectl",
+		"show",
+	}
+
+	client, err := kubernetes.NewForConfig(config)
+	if err != nil {
+		return "", err
+	}
+
+	//TODO: Don't hardcode namespace
+	//TODO: Use controller-runtime client ?
+	handlerPodList, err := client.CoreV1().Pods("nmstate").List(context.Background(), metav1.ListOptions{
+		LabelSelector: "component=kubernetes-nmstate-handler",
+		FieldSelector: fmt.Sprintf("spec.nodeName=%s", nodeName),
+	})
+	if err != nil {
+		return "", err
+	}
+	if len(handlerPodList.Items) == 0 {
+		return "", fmt.Errorf("No handler running at %s", nodeName)
+	}
+	//TODO: Don't hardcode namespace
+	req := client.CoreV1().RESTClient().Post().Resource("pods").Name(handlerPodList.Items[0].Name).
+		Namespace("nmstate").SubResource("exec")
+	option := &v1.PodExecOptions{
+		Command: cmd,
+		Stdin:   false,
+		Stdout:  true,
+		Stderr:  true,
+		TTY:     false,
+	}
+	req.VersionedParams(
+		option,
+		scheme.ParameterCodec,
+	)
+	exec, err := remotecommand.NewSPDYExecutor(config, "POST", req.URL())
+	if err != nil {
+		return "", err
+	}
+	var stdout, stderr bytes.Buffer
+	err = exec.Stream(remotecommand.StreamOptions{
+		Stdout: &stdout,
+		Stderr: &stderr,
+	})
+	if err != nil {
+		return "", err
+	}
+	return stdout.String(), nil
+}
diff --git a/pkg/state/filter.go b/pkg/state/filter.go
index cb7d4c55f0..a98ad6a851 100644
--- a/pkg/state/filter.go
+++ b/pkg/state/filter.go
@@ -58,9 +58,24 @@ func filterOutDynamicAttributes(iface map[string]interface{}) {
 		return
 	}
 
-	bridge := iface["bridge"].(map[string]interface{})
+	bridgeIface, ok := iface["bridge"]
+	if !ok {
+		return
+	}
+	bridge, ok := bridgeIface.(map[string]interface{})
+	if !ok {
+		return
+	}
+
+	optionsIface, ok := bridge["options"]
+	if !ok {
+		return
+	}
+	options, ok := optionsIface.(map[string]interface{})
+	if !ok {
+		return
+	}
 
-	options := bridge["options"].(map[string]interface{})
 	delete(options, "gc-timer")
 	delete(options, "hello-timer")
 }
diff --git a/pkg/state/filter_test.go b/pkg/state/filter_test.go
index 3f49f13a09..1549daab00 100644
--- a/pkg/state/filter_test.go
+++ b/pkg/state/filter_test.go
@@ -307,4 +307,66 @@ routes:
 			Expect(returnedState).To(MatchYAML(filteredState))
 		})
 	})
+	Context("when there is a linux bridge without 'bridge' options because is down", func() {
+		BeforeEach(func() {
+			state = nmstate.NewState(`
+interfaces:
+- name: eth1
+  state: up
+  type: ethernet
+- name: br1
+  type: linux-bridge
+  state: down
+  ipv4:
+    enabled: false
+  ipv6:
+    enabled: false
+  lldp:
+    enabled: false
+  mac-address: A2:EE:84:7B:42:4C
+  mtu: 1500
+routes:
+  config: []
+  running:
+  - destination: 0.0.0.0/0
+    metric: 102
+    next-hop-address: 192.168.66.2
+    next-hop-interface: eth1
+    table-id: 254
+`)
+
+			filteredState = nmstate.NewState(`
+interfaces:
+- name: eth1
+  state: up
+  type: ethernet
+- name: br1
+  type: linux-bridge
+  state: down
+  ipv4:
+    enabled: false
+  ipv6:
+    enabled: false
+  lldp:
+    enabled: false
+  mac-address: A2:EE:84:7B:42:4C
+  mtu: 1500
+routes:
+  config: []
+  running:
+  - destination: 0.0.0.0/0
+    metric: 102
+    next-hop-address: 192.168.66.2
+    next-hop-interface: eth1
+    table-id: 254
+`)
+			interfacesFilterGlob = glob.MustCompile("")
+		})
+		It("should keep the bridge as it is", func() {
+			returnedState, err := filterOut(state, interfacesFilterGlob)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(returnedState).To(MatchYAML(filteredState))
+		})
+	})
+
 })