Bug 1940141

Summary: Permissive Egress NetworkPolicy (0.0.0.0/0) is blocking all traffic
Product: OpenShift Container Platform Reporter: Michał Dulko <mdulko>
Component: NetworkingAssignee: Michał Dulko <mdulko>
Networking sub component: kuryr QA Contact: Jon Uriarte <juriarte>
Status: CLOSED ERRATA Docs Contact:
Severity: medium    
Priority: medium CC: amuller, bbennett, chrisw, gcheresh, jdelft, juriarte, ltomasbo, mdulko, mpatercz, openshift-bugzilla-robot, ralonsoh, rdobosz, rlobillo, scohen
Version: 4.6.z   
Target Milestone: ---   
Target Release: 4.6.z   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: 1938960 Environment:
Last Closed: 2021-04-20 19:27:22 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 1938960, 1952429    
Bug Blocks: 1947343    

Comment 3 Jon Uriarte 2021-03-30 12:38:45 UTC 
Verified in 4.6.0-0.nightly-2021-03-27-052141 on top of OSP 16.1.4 (RHOS-16.1-RHEL-8-20210311.n.1) with OVN-Octavia.

SG rules generated by below NP resource definition allow egress traffic for all protocols and not only TCP:

kind: NetworkPolicy
apiVersion: networking.k8s.io/v1
metadata:
  name: np-bz1940141
spec:
  podSelector:
    matchLabels:
      run: demo
  policyTypes:
  - Egress
  - Ingress
  ingress:
  - from:
    - podSelector: {}
  egress:
  - to:
    - ipBlock:
        cidr: 0.0.0.0/0

Steps:

1. Create test and test2 projects both with kuryr/demo pod exposed by a service on port 80:

$ oc new-project test
$ oc run --image kuryr/demo demo
$ oc expose pod/demo --port 80 --target-port 8080
$ oc get all -n test
NAME       READY   STATUS    RESTARTS   AGE
pod/demo   1/1     Running   0          44s

NAME           TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)   AGE
service/demo   ClusterIP   172.30.100.174   <none>        80/TCP    14s

$ oc new-project test2
$ oc run --image kuryr/demo demo2
$ oc expose pod/demo2 --port 80 --target-port 8080
$ oc get all -n test2
NAME        READY   STATUS    RESTARTS   AGE
pod/demo2   1/1     Running   0          21s

NAME            TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)   AGE
service/demo2   ClusterIP   172.30.254.31   <none>        80/TCP    4s


2. Apply np on demo pod in test project:

$ cat np_bz1940141.yaml 
kind: NetworkPolicy
apiVersion: networking.k8s.io/v1
metadata:
  name: np-bz1940141
spec:
  podSelector:
    matchLabels:
      run: demo
  policyTypes:
  - Egress
  - Ingress
  ingress:
  - from:
    - podSelector: {}
  egress:
  - to:
    - ipBlock:
        cidr: 0.0.0.0/0

$ oc apply -f np_bz1940141.yaml -n test

# knp resource generated includes Egress rule apply to IPv4 traffic, 
not only TCP, but also UDP

$ oc -n test get knp/np-bz1940141 -o json | jq .spec
{                                                                                                                                                                                                                                             
  "egressSgRules": [                                                                                                                                                                                                                          
    {
      "sgRule": {
        "description": "Kuryr-Kubernetes NetPolicy SG rule",
        "direction": "egress",
        "ethertype": "IPv4",
        "port_range_max": 65535,
        "port_range_min": 1,
        "remote_ip_prefix": "0.0.0.0/0"
      }
    },
    {
      "sgRule": {
        "description": "Kuryr-Kubernetes NetPolicy SG rule",
        "direction": "egress",
        "ethertype": "IPv4",
        "remote_ip_prefix": "172.30.100.174"
      }
    }
  ],
  "ingressSgRules": [
    {
      "namespace": "test",
      "sgRule": {
        "description": "Kuryr-Kubernetes NetPolicy SG rule",
        "direction": "ingress",
        "ethertype": "IPv4",
        "port_range_max": 65535,
        "port_range_min": 1,
        "remote_ip_prefix": "10.128.120.0/23"
      }
    },
    {
      "sgRule": {
        "description": "Kuryr-Kubernetes NetPolicy SG rule",
        "direction": "ingress",
        "ethertype": "IPv4",
        "remote_ip_prefix": "10.196.0.0/16"
      }
    }
  ],
  "podSelector": {
    "matchLabels": {
      "run": "demo"
    }
  },
  "policyTypes": [
    "Egress",
    "Ingress"
  ]
}


3. Test connectivity:

$ oc rsh -n test demo

1. Ping to external domain:
~ $ curl -s www.google.com
<!doctype html><html dir="rtl" itemscope="" itemtype="http://schema.org/
WebPage" lang="iw"><head><meta content="text/html; charset=UTF-8" http-e
quiv="Content-Type"><meta content="/images/branding/googleg/1x/googleg_s
tandard_color_128dp.png" itemprop="image"><title>Google</title><script n
once="tmGrp9BOgBuSGdMD4i89gA==">(function(){window.google={kEI:'3IUzYKu_
IsmVsAfT8o6oDg',kEXPI:'0,18168,1284265[...]

2. Curl the other namespace:
~ $ curl 172.30.254.31
demo2: HELLO! I AM ALIVE!!!
Comment 4 Michał Dulko 2021-04-07 16:16:16 UTC 
Back to POST as we've found an issue caused by this patch.
Comment 5 Michał Dulko 2021-04-08 09:23:04 UTC 
Back to VERIFIED, I should better create a new bug.
Comment 10 errata-xmlrpc 2021-04-20 19:27:22 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (OpenShift Container Platform 4.6.25 bug fix update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2021:1153
Comment 11 Michał Dulko 2021-05-07 08:54:04 UTC 
*** Bug 1952429 has been marked as a duplicate of this bug. ***