From 53ed8e04ae41aabd67f8e0283930746ce2afbc87 Mon Sep 17 00:00:00 2001
From: Ludovic Fernandez <ldez@users.noreply.github.com>
Date: Mon, 23 Nov 2020 12:00:03 +0100
Subject: [PATCH 01/14] Update go-acme/lego to v4.1.2

---
 go.mod | 2 +-
 go.sum | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/go.mod b/go.mod
index 04adf5f48..6010bad44 100644
--- a/go.mod
+++ b/go.mod
@@ -35,7 +35,7 @@ require (
 	github.com/fatih/structs v1.1.0
 	github.com/flynn/go-shlex v0.0.0-20150515145356-3f9db97f8568 // indirect
 	github.com/gambol99/go-marathon v0.0.0-20180614232016-99a156b96fb2
-	github.com/go-acme/lego/v4 v4.1.0
+	github.com/go-acme/lego/v4 v4.1.2
 	github.com/go-check/check v0.0.0-00010101000000-000000000000
 	github.com/go-kit/kit v0.10.1-0.20200915143503-439c4d2ed3ea
 	github.com/golang/protobuf v1.3.4
diff --git a/go.sum b/go.sum
index d4e35bcf7..b0ff75b08 100644
--- a/go.sum
+++ b/go.sum
@@ -275,8 +275,8 @@ github.com/gambol99/go-marathon v0.0.0-20180614232016-99a156b96fb2/go.mod h1:GLy
 github.com/ghodss/yaml v0.0.0-20150909031657-73d445a93680/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
 github.com/ghodss/yaml v1.0.0 h1:wQHKEahhL6wmXdzwWG11gIVCkOv05bNOh+Rxn0yngAk=
 github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
-github.com/go-acme/lego/v4 v4.1.0 h1:/9pMjaeaLq6m0n+io+kv2ySs2ZfrmH6eazuMoN18GHo=
-github.com/go-acme/lego/v4 v4.1.0/go.mod h1:pIFm5tWkXSgiAEfJ/XQCQIvX1cEvHFwbgLZyx8OVSUE=
+github.com/go-acme/lego/v4 v4.1.2 h1:1zROppXkTbAIh7J7AydGD3dFICLIocucJY1NTH/wB64=
+github.com/go-acme/lego/v4 v4.1.2/go.mod h1:pIFm5tWkXSgiAEfJ/XQCQIvX1cEvHFwbgLZyx8OVSUE=
 github.com/go-cmd/cmd v1.0.5/go.mod h1:y8q8qlK5wQibcw63djSl/ntiHUHXHGdCkPk0j4QeW4s=
 github.com/go-errors/errors v1.0.1 h1:LUHzmkK3GUKUrL/1gfBUxAHzcev3apQlezX/+O7ma6w=
 github.com/go-errors/errors v1.0.1/go.mod h1:f4zRHt4oKfwPJE5k8C9vpYG+aDHdBFUsgrm6/TyX73Q=

From 1c505903ff8ae20821b84dabcf08c104b8001e18 Mon Sep 17 00:00:00 2001
From: Ludovic Fernandez <ldez@users.noreply.github.com>
Date: Tue, 24 Nov 2020 09:40:03 +0100
Subject: [PATCH 02/14] fix: invalid slice parsing.

---
 go.mod | 2 +-
 go.sum | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/go.mod b/go.mod
index 6010bad44..76298aa9f 100644
--- a/go.mod
+++ b/go.mod
@@ -72,7 +72,7 @@ require (
 	github.com/stretchr/testify v1.6.1
 	github.com/stvp/go-udp-testing v0.0.0-20191102171040-06b61409b154
 	github.com/tinylib/msgp v1.0.2 // indirect
-	github.com/traefik/paerser v0.1.0
+	github.com/traefik/paerser v0.1.1
 	github.com/traefik/yaegi v0.9.7
 	github.com/uber/jaeger-client-go v2.25.0+incompatible
 	github.com/uber/jaeger-lib v2.2.0+incompatible
diff --git a/go.sum b/go.sum
index b0ff75b08..eec9c67e5 100644
--- a/go.sum
+++ b/go.sum
@@ -764,8 +764,8 @@ github.com/tinylib/msgp v1.0.2/go.mod h1:+d+yLhGm8mzTaHzB+wgMYrodPfmZrzkirds8fDW
 github.com/tmc/grpc-websocket-proxy v0.0.0-20170815181823-89b8d40f7ca8/go.mod h1:ncp9v5uamzpCO7NfCPTXjqaC+bZgJeR0sMTm6dMHP7U=
 github.com/tmc/grpc-websocket-proxy v0.0.0-20190109142713-0ad062ec5ee5 h1:LnC5Kc/wtumK+WB441p7ynQJzVuNRJiqddSIE3IlSEQ=
 github.com/tmc/grpc-websocket-proxy v0.0.0-20190109142713-0ad062ec5ee5/go.mod h1:ncp9v5uamzpCO7NfCPTXjqaC+bZgJeR0sMTm6dMHP7U=
-github.com/traefik/paerser v0.1.0 h1:B4v1tbvd8YnHsA7spwHKEWJoGrRP+2jYpIozsCMHhl0=
-github.com/traefik/paerser v0.1.0/go.mod h1:yYnAgdEC2wJH5CgG75qGWC8SsFDEapg09o9RrA6FfrE=
+github.com/traefik/paerser v0.1.1 h1:Suj0iA4hTAV6E4Dh5/++TXAj5u6iTwydBlFssIUz+9w=
+github.com/traefik/paerser v0.1.1/go.mod h1:yYnAgdEC2wJH5CgG75qGWC8SsFDEapg09o9RrA6FfrE=
 github.com/traefik/yaegi v0.9.7 h1:CbeKjEhy3DoSC8xC4TQF2Mhmd7u3Cjqluz1//x6Vtcs=
 github.com/traefik/yaegi v0.9.7/go.mod h1:FAYnRlZyuVlEkvnkHq3bvJ1lW5be6XuwgLdkYgYG6Lk=
 github.com/transip/gotransip/v6 v6.2.0 h1:0Z+qVsyeiQdWfcAUeJyF0IEKAPvhJwwpwPi2WGtBIiE=

From e9cccf6504764aab9a37e77a764da8f1a2159a42 Mon Sep 17 00:00:00 2001
From: Harold Ozouf <harold.ozouf@gmail.com>
Date: Tue, 24 Nov 2020 14:16:03 +0100
Subject: [PATCH 03/14] Do not evaluate templated URL in redirectRegex
 middleware

---
 pkg/middlewares/redirect/redirect.go          | 31 +++----------------
 .../redirect/redirect_regex_test.go           | 13 +-------
 2 files changed, 6 insertions(+), 38 deletions(-)

diff --git a/pkg/middlewares/redirect/redirect.go b/pkg/middlewares/redirect/redirect.go
index 9f6939474..e58422315 100644
--- a/pkg/middlewares/redirect/redirect.go
+++ b/pkg/middlewares/redirect/redirect.go
@@ -1,9 +1,6 @@
 package redirect
 
 import (
-	"bytes"
-	"html/template"
-	"io"
 	"net/http"
 	"net/url"
 	"regexp"
@@ -47,24 +44,17 @@ func (r *redirect) GetTracingInformation() (string, ext.SpanKindEnum) {
 func (r *redirect) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
 	oldURL := rawURL(req)
 
-	// If the Regexp doesn't match, skip to the next handler
+	// If the Regexp doesn't match, skip to the next handler.
 	if !r.regex.MatchString(oldURL) {
 		r.next.ServeHTTP(rw, req)
 		return
 	}
 
-	// apply a rewrite regexp to the URL
+	// Apply a rewrite regexp to the URL.
 	newURL := r.regex.ReplaceAllString(oldURL, r.replacement)
 
-	// replace any variables that may be in there
-	rewrittenURL := &bytes.Buffer{}
-	if err := applyString(newURL, rewrittenURL, req); err != nil {
-		r.errHandler.ServeHTTP(rw, req, err)
-		return
-	}
-
-	// parse the rewritten URL and replace request URL with it
-	parsedURL, err := url.Parse(rewrittenURL.String())
+	// Parse the rewritten URL and replace request URL with it.
+	parsedURL, err := url.Parse(newURL)
 	if err != nil {
 		r.errHandler.ServeHTTP(rw, req, err)
 		return
@@ -78,7 +68,7 @@ func (r *redirect) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
 
 	req.URL = parsedURL
 
-	// make sure the request URI corresponds the rewritten URL
+	// Make sure the request URI corresponds the rewritten URL.
 	req.RequestURI = req.URL.RequestURI()
 	r.next.ServeHTTP(rw, req)
 }
@@ -138,14 +128,3 @@ func rawURL(req *http.Request) string {
 
 	return strings.Join([]string{scheme, "://", host, port, uri}, "")
 }
-
-func applyString(in string, out io.Writer, req *http.Request) error {
-	t, err := template.New("t").Parse(in)
-	if err != nil {
-		return err
-	}
-
-	data := struct{ Request *http.Request }{Request: req}
-
-	return t.Execute(out, data)
-}
diff --git a/pkg/middlewares/redirect/redirect_regex_test.go b/pkg/middlewares/redirect/redirect_regex_test.go
index bc9f08242..d6346cf75 100644
--- a/pkg/middlewares/redirect/redirect_regex_test.go
+++ b/pkg/middlewares/redirect/redirect_regex_test.go
@@ -10,7 +10,6 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"github.com/traefik/traefik/v2/pkg/config/dynamic"
-	"github.com/traefik/traefik/v2/pkg/testhelpers"
 )
 
 func TestRedirectRegexHandler(t *testing.T) {
@@ -35,16 +34,6 @@ func TestRedirectRegexHandler(t *testing.T) {
 			expectedURL:    "https://foobar.com:443",
 			expectedStatus: http.StatusFound,
 		},
-		{
-			desc: "use request header",
-			config: dynamic.RedirectRegex{
-				Regex:       `^(?:http?:\/\/)(foo)(\.com)(:\d+)(.*)$`,
-				Replacement: `https://${1}{{ .Request.Header.Get "X-Foo" }}$2:443$4`,
-			},
-			url:            "http://foo.com:80",
-			expectedURL:    "https://foobar.com:443",
-			expectedStatus: http.StatusFound,
-		},
 		{
 			desc: "URL doesn't match regex",
 			config: dynamic.RedirectRegex{
@@ -186,7 +175,7 @@ func TestRedirectRegexHandler(t *testing.T) {
 					method = test.method
 				}
 
-				req := testhelpers.MustNewRequest(method, test.url, nil)
+				req := httptest.NewRequest(method, test.url, nil)
 				if test.secured {
 					req.TLS = &tls.ConnectionState{}
 				}

From d2c1d39d423674e3d7b98a3322fe120b7714ceb7 Mon Sep 17 00:00:00 2001
From: SkapiN <skapinthefourb@gmail.com>
Date: Tue, 24 Nov 2020 14:50:03 +0100
Subject: [PATCH 04/14] Fix clusters option in ECS provider documentation

---
 docs/content/providers/ecs.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/content/providers/ecs.md b/docs/content/providers/ecs.md
index ab860c524..7a4afa92c 100644
--- a/docs/content/providers/ecs.md
+++ b/docs/content/providers/ecs.md
@@ -87,7 +87,7 @@ _Optional, Default=["default"]_
 
 ```toml tab="File (TOML)"
 [providers.ecs]
-  cluster = ["default"]
+  clusters = ["default"]
   # ...
 ```
 

From 76e35a09b76be4dc4833d2d867d3ea8169c8ea75 Mon Sep 17 00:00:00 2001
From: Kevin Pollet <pollet.kevin@gmail.com>
Date: Tue, 24 Nov 2020 17:06:04 +0100
Subject: [PATCH 05/14] Prepare release v2.3.4

---
 CHANGELOG.md                   | 12 ++++++++++++
 script/gcg/traefik-bugfix.toml |  6 +++---
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 35864f514..0f718aead 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,15 @@
+## [v2.3.4](https://github.com/traefik/traefik/tree/v2.3.4) (2020-11-24)
+[All Commits](https://github.com/traefik/traefik/compare/v2.3.3...v2.3.4)
+
+**Bug fixes:**
+- **[acme]** Update go-acme/lego to v4.1.2 ([#7577](https://github.com/traefik/traefik/pull/7577) by [ldez](https://github.com/ldez))
+- **[k8s,k8s/crd,k8s/ingress]** Apply labelSelector as a TweakListOptions for Kubernetes informers ([#7521](https://github.com/traefik/traefik/pull/7521) by [rtribotte](https://github.com/rtribotte))
+- **[middleware]** Do not evaluate templated URL in redirectRegex middleware ([#7573](https://github.com/traefik/traefik/pull/7573) by [jspdown](https://github.com/jspdown))
+- **[provider]** fix: invalid slice parsing. ([#7583](https://github.com/traefik/traefik/pull/7583) by [ldez](https://github.com/ldez))
+
+**Documentation:**
+- **[ecs]** Fix clusters option in ECS provider documentation ([#7586](https://github.com/traefik/traefik/pull/7586) by [skapin](https://github.com/skapin))
+
 ## [v2.3.3](https://github.com/traefik/traefik/tree/v2.3.3) (2020-11-19)
 [All Commits](https://github.com/traefik/traefik/compare/v2.3.2...v2.3.3)
 
diff --git a/script/gcg/traefik-bugfix.toml b/script/gcg/traefik-bugfix.toml
index 0a4e2f244..3b6392736 100644
--- a/script/gcg/traefik-bugfix.toml
+++ b/script/gcg/traefik-bugfix.toml
@@ -4,11 +4,11 @@ RepositoryName = "traefik"
 OutputType = "file"
 FileName = "traefik_changelog.md"
 
-# example new bugfix v2.3.3
+# example new bugfix v2.3.4
 CurrentRef = "v2.3"
-PreviousRef = "v2.3.2"
+PreviousRef = "v2.3.3"
 BaseBranch = "v2.3"
-FutureCurrentRefName = "v2.3.3"
+FutureCurrentRefName = "v2.3.4"
 
 ThresholdPreviousRef = 10
 ThresholdCurrentRef = 10

From 512ed086bd237dbde14294eea75ba1910ecae54e Mon Sep 17 00:00:00 2001
From: Sergiu Marsavela <marsavela@gmail.com>
Date: Fri, 27 Nov 2020 11:18:04 +0100
Subject: [PATCH 06/14] Fix typos in migration guide

---
 docs/content/migration/v1-to-v2.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/content/migration/v1-to-v2.md b/docs/content/migration/v1-to-v2.md
index 7840726ed..3c0c58080 100644
--- a/docs/content/migration/v1-to-v2.md
+++ b/docs/content/migration/v1-to-v2.md
@@ -385,7 +385,7 @@ To apply a redirection:
     
     entryPoints:
       web:
-        address: 80
+        address: ":80"
         http:
           redirections:
             entrypoint:
@@ -393,7 +393,7 @@ To apply a redirection:
               scheme: https
     
       websecure:
-        address: 443
+        address: ":443"
     ```
 
 !!! example "HTTP to HTTPS redirection per domain"

From 121eaced490f5cef4ab1ffba0d00a9cb0ef50d3c Mon Sep 17 00:00:00 2001
From: Kevin Crawley <3759919+notsureifkevin@users.noreply.github.com>
Date: Thu, 3 Dec 2020 02:36:03 -0600
Subject: [PATCH 07/14] Add example for multiple service per container

---
 docs/content/routing/providers/docker.md | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/docs/content/routing/providers/docker.md b/docs/content/routing/providers/docker.md
index 6cc0cf2a8..d3af40057 100644
--- a/docs/content/routing/providers/docker.md
+++ b/docs/content/routing/providers/docker.md
@@ -58,6 +58,26 @@ Attach labels to your containers and let Traefik do the rest!
         Setting the label `traefik.http.services.xxx.loadbalancer.server.port`
         overrides that behavior.
 
+??? example "Specifying more than one router and service per container"
+
+    Forwarding requests to more than one port on a container requires referencing the service loadbalancer port definition using the service parameter on the router.
+
+    In this example, requests are forwarded for `http://example-a.com` to `http://<private IP of container>:8000` in addition to `http://example-b.com` forwarding to `http://<private IP of container>:9000`:
+
+    ```yaml
+    version: "3"
+    services:
+      my-container:
+        # ...
+        labels:
+          - traefik.http.routers.www-router.rule=Host(`example-a.com`)
+          - traefik.http.routers.www-router.service=www-service
+          - traefik.http.services.www-service.loadbalancer.server.port=8000
+          - traefik.http.routers.admin-router.rule=Host(`example-b.com`)
+          - traefik.http.routers.admin-router.service=admin-service
+          - traefik.http.services.admin-service.loadbalancer.server.port=9000
+    ```
+
 ??? example "Configuring Docker Swarm & Deploying / Exposing Services"
 
     Enabling the docker provider (Swarm Mode)

From 7403b6fb82582e96cdd0a2e57451bfcd10eabb8c Mon Sep 17 00:00:00 2001
From: Harold Ozouf <harold.ozouf@gmail.com>
Date: Fri, 4 Dec 2020 20:56:04 +0100
Subject: [PATCH 08/14] Fix concatenation of IPv6 addresses and ports

---
 .../kubernetes/crd/fixtures/services.yml      |  44 ++++++-
 .../kubernetes/crd/fixtures/tcp/services.yml  |  42 +++++-
 .../kubernetes/crd/fixtures/tcp/with_ipv6.yml |  17 +++
 .../kubernetes/crd/fixtures/udp/services.yml  |  29 +++++
 .../kubernetes/crd/fixtures/udp/with_ipv6.yml |  14 ++
 .../kubernetes/crd/fixtures/with_ipv6.yml     |  18 +++
 .../kubernetes/crd/kubernetes_http.go         |  10 +-
 pkg/provider/kubernetes/crd/kubernetes_tcp.go |   6 +-
 .../kubernetes/crd/kubernetes_test.go         | 122 ++++++++++++++++++
 pkg/provider/kubernetes/crd/kubernetes_udp.go |   6 +-
 .../Ingress-with-IPv6-endpoints_endpoint.yml  |  12 ++
 .../Ingress-with-IPv6-endpoints_ingress.yml   |  18 +++
 .../Ingress-with-IPv6-endpoints_service.yml   |  26 ++++
 pkg/provider/kubernetes/ingress/kubernetes.go |   9 +-
 .../kubernetes/ingress/kubernetes_test.go     |  41 ++++++
 15 files changed, 403 insertions(+), 11 deletions(-)
 create mode 100644 pkg/provider/kubernetes/crd/fixtures/tcp/with_ipv6.yml
 create mode 100644 pkg/provider/kubernetes/crd/fixtures/udp/with_ipv6.yml
 create mode 100644 pkg/provider/kubernetes/crd/fixtures/with_ipv6.yml
 create mode 100644 pkg/provider/kubernetes/ingress/fixtures/Ingress-with-IPv6-endpoints_endpoint.yml
 create mode 100644 pkg/provider/kubernetes/ingress/fixtures/Ingress-with-IPv6-endpoints_ingress.yml
 create mode 100644 pkg/provider/kubernetes/ingress/fixtures/Ingress-with-IPv6-endpoints_service.yml

diff --git a/pkg/provider/kubernetes/crd/fixtures/services.yml b/pkg/provider/kubernetes/crd/fixtures/services.yml
index 72b2e1b16..50d6d65c6 100644
--- a/pkg/provider/kubernetes/crd/fixtures/services.yml
+++ b/pkg/provider/kubernetes/crd/fixtures/services.yml
@@ -119,6 +119,35 @@ subsets:
       - name: websecure2
         port: 8443
 
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: whoami-ipv6
+  namespace: default
+
+spec:
+  ports:
+    - name: web
+      port: 8080
+  selector:
+    app: traefiklabs
+    task: whoami-ipv6
+
+---
+kind: Endpoints
+apiVersion: v1
+metadata:
+  name: whoami-ipv6
+  namespace: default
+
+subsets:
+  - addresses:
+      - ip: "2001:db8:85a3:8d3:1319:8a2e:370:7348"
+    ports:
+      - name: web
+        port: 8080
+
 ---
 apiVersion: v1
 kind: Service
@@ -157,5 +186,16 @@ spec:
       protocol: TCP
       port: 443
 
-
-
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: external-svc-with-ipv6
+  namespace: default
+spec:
+  externalName: "2001:db8:85a3:8d3:1319:8a2e:370:7347"
+  type: ExternalName
+  ports:
+    - name: http
+      protocol: TCP
+      port: 8080
diff --git a/pkg/provider/kubernetes/crd/fixtures/tcp/services.yml b/pkg/provider/kubernetes/crd/fixtures/tcp/services.yml
index 7aabcb9be..32a854c8a 100644
--- a/pkg/provider/kubernetes/crd/fixtures/tcp/services.yml
+++ b/pkg/provider/kubernetes/crd/fixtures/tcp/services.yml
@@ -132,6 +132,36 @@ subsets:
       - name: myapp4
         port: 8084
 
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: whoamitcp-ipv6
+  namespace: default
+
+spec:
+  ports:
+    - name: myapp-ipv6
+      port: 8080
+  selector:
+    app: traefiklabs
+    task: whoamitcp-ipv6
+
+---
+kind: Endpoints
+apiVersion: v1
+metadata:
+  name: whoamitcp-ipv6
+  namespace: default
+
+subsets:
+  - addresses:
+      - ip: "fd00:10:244:0:1::3"
+      - ip: "2001:db8:85a3:8d3:1319:8a2e:370:7348"
+    ports:
+      - name: myapp-ipv6
+        port: 8080
+
 ---
 apiVersion: v1
 kind: Service
@@ -167,4 +197,14 @@ spec:
   type: ExternalName
   ports:
     - name: http
-      protocol: TCP
\ No newline at end of file
+      protocol: TCP
+
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: external.service.with.ipv6
+  namespace: default
+spec:
+  externalName: "fe80::200:5aee:feaa:20a2"
+  type: ExternalName
diff --git a/pkg/provider/kubernetes/crd/fixtures/tcp/with_ipv6.yml b/pkg/provider/kubernetes/crd/fixtures/tcp/with_ipv6.yml
new file mode 100644
index 000000000..777915c18
--- /dev/null
+++ b/pkg/provider/kubernetes/crd/fixtures/tcp/with_ipv6.yml
@@ -0,0 +1,17 @@
+apiVersion: traefik.containo.us/v1alpha1
+kind: IngressRouteTCP
+metadata:
+  name: test.route
+  namespace: default
+
+spec:
+  entryPoints:
+    - foo
+
+  routes:
+  - match: HostSNI(`*`)
+    services:
+    - name: whoamitcp-ipv6
+      port: 8080
+    - name: external.service.with.ipv6
+      port: 8080
diff --git a/pkg/provider/kubernetes/crd/fixtures/udp/services.yml b/pkg/provider/kubernetes/crd/fixtures/udp/services.yml
index c1a589cb6..f1c0abe18 100644
--- a/pkg/provider/kubernetes/crd/fixtures/udp/services.yml
+++ b/pkg/provider/kubernetes/crd/fixtures/udp/services.yml
@@ -101,3 +101,32 @@ subsets:
     ports:
       - name: myapp4
         port: 8084
+
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: whoamiudp-ipv6
+  namespace: default
+
+spec:
+  ports:
+    - name: myapp-ipv6
+      port: 8080
+  selector:
+    app: traefiklabs
+    task: whoamiudp-ipv6
+
+---
+kind: Endpoints
+apiVersion: v1
+metadata:
+  name: whoamiudp-ipv6
+  namespace: default
+
+subsets:
+  - addresses:
+      - ip: "fd00:10:244:0:1::3"
+    ports:
+      - name: myapp-ipv6
+        port: 8080
diff --git a/pkg/provider/kubernetes/crd/fixtures/udp/with_ipv6.yml b/pkg/provider/kubernetes/crd/fixtures/udp/with_ipv6.yml
new file mode 100644
index 000000000..2acc8bdc7
--- /dev/null
+++ b/pkg/provider/kubernetes/crd/fixtures/udp/with_ipv6.yml
@@ -0,0 +1,14 @@
+apiVersion: traefik.containo.us/v1alpha1
+kind: IngressRouteUDP
+metadata:
+  name: test.route
+  namespace: default
+
+spec:
+  entryPoints:
+    - foo
+
+  routes:
+  - services:
+    - name: whoamiudp-ipv6
+      port: 8080
diff --git a/pkg/provider/kubernetes/crd/fixtures/with_ipv6.yml b/pkg/provider/kubernetes/crd/fixtures/with_ipv6.yml
new file mode 100644
index 000000000..23af879ac
--- /dev/null
+++ b/pkg/provider/kubernetes/crd/fixtures/with_ipv6.yml
@@ -0,0 +1,18 @@
+apiVersion: traefik.containo.us/v1alpha1
+kind: IngressRoute
+metadata:
+  name: test.route
+  namespace: default
+
+spec:
+  entryPoints:
+    - foo
+
+  routes:
+    - match: Host(`foo.com`) && PathPrefix(`/bar`)
+      kind: Rule
+      services:
+        - name: whoami-ipv6
+          port: 8080
+        - name: external-svc-with-ipv6
+          port: 8080
diff --git a/pkg/provider/kubernetes/crd/kubernetes_http.go b/pkg/provider/kubernetes/crd/kubernetes_http.go
index 9a28bbf43..1a40c561c 100644
--- a/pkg/provider/kubernetes/crd/kubernetes_http.go
+++ b/pkg/provider/kubernetes/crd/kubernetes_http.go
@@ -4,6 +4,8 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"net"
+	"strconv"
 	"strings"
 
 	"github.com/traefik/traefik/v2/pkg/config/dynamic"
@@ -301,8 +303,10 @@ func (c configBuilder) loadServers(fallbackNamespace string, svc v1alpha1.LoadBa
 			return nil, err
 		}
 
+		hostPort := net.JoinHostPort(service.Spec.ExternalName, strconv.Itoa(int(svcPort.Port)))
+
 		return append(servers, dynamic.Server{
-			URL: fmt.Sprintf("%s://%s:%d", protocol, service.Spec.ExternalName, svcPort.Port),
+			URL: fmt.Sprintf("%s://%s", protocol, hostPort),
 		}), nil
 	}
 
@@ -336,8 +340,10 @@ func (c configBuilder) loadServers(fallbackNamespace string, svc v1alpha1.LoadBa
 		}
 
 		for _, addr := range subset.Addresses {
+			hostPort := net.JoinHostPort(addr.IP, strconv.Itoa(int(port)))
+
 			servers = append(servers, dynamic.Server{
-				URL: fmt.Sprintf("%s://%s:%d", protocol, addr.IP, port),
+				URL: fmt.Sprintf("%s://%s", protocol, hostPort),
 			})
 		}
 	}
diff --git a/pkg/provider/kubernetes/crd/kubernetes_tcp.go b/pkg/provider/kubernetes/crd/kubernetes_tcp.go
index 49cff4e60..abf29bb8e 100644
--- a/pkg/provider/kubernetes/crd/kubernetes_tcp.go
+++ b/pkg/provider/kubernetes/crd/kubernetes_tcp.go
@@ -4,6 +4,8 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"net"
+	"strconv"
 	"strings"
 
 	"github.com/traefik/traefik/v2/pkg/config/dynamic"
@@ -165,7 +167,7 @@ func loadTCPServers(client Client, namespace string, svc v1alpha1.ServiceTCP) ([
 	var servers []dynamic.TCPServer
 	if service.Spec.Type == corev1.ServiceTypeExternalName {
 		servers = append(servers, dynamic.TCPServer{
-			Address: fmt.Sprintf("%s:%d", service.Spec.ExternalName, svcPort.Port),
+			Address: net.JoinHostPort(service.Spec.ExternalName, strconv.Itoa(int(svcPort.Port))),
 		})
 	} else {
 		endpoints, endpointsExists, endpointsErr := client.GetEndpoints(namespace, svc.Name)
@@ -196,7 +198,7 @@ func loadTCPServers(client Client, namespace string, svc v1alpha1.ServiceTCP) ([
 
 			for _, addr := range subset.Addresses {
 				servers = append(servers, dynamic.TCPServer{
-					Address: fmt.Sprintf("%s:%d", addr.IP, port),
+					Address: net.JoinHostPort(addr.IP, strconv.Itoa(int(port))),
 				})
 			}
 		}
diff --git a/pkg/provider/kubernetes/crd/kubernetes_test.go b/pkg/provider/kubernetes/crd/kubernetes_test.go
index 73ed3588f..b866f20cb 100644
--- a/pkg/provider/kubernetes/crd/kubernetes_test.go
+++ b/pkg/provider/kubernetes/crd/kubernetes_test.go
@@ -987,6 +987,128 @@ func TestLoadIngressRouteTCPs(t *testing.T) {
 				TLS: &dynamic.TLSConfiguration{},
 			},
 		},
+		{
+			desc: "Ingress Route with IPv6 backends",
+			paths: []string{
+				"services.yml", "with_ipv6.yml",
+				"tcp/services.yml", "tcp/with_ipv6.yml",
+				"udp/services.yml", "udp/with_ipv6.yml",
+			},
+			expected: &dynamic.Configuration{
+				UDP: &dynamic.UDPConfiguration{
+					Routers: map[string]*dynamic.UDPRouter{
+						"default-test.route-0": {
+							EntryPoints: []string{"foo"},
+							Service:     "default-test.route-0",
+						},
+					},
+					Services: map[string]*dynamic.UDPService{
+						"default-test.route-0": {
+							LoadBalancer: &dynamic.UDPServersLoadBalancer{
+								Servers: []dynamic.UDPServer{
+									{
+										Address: "[fd00:10:244:0:1::3]:8080",
+									},
+								},
+							},
+						},
+					},
+				},
+				TCP: &dynamic.TCPConfiguration{
+					Routers: map[string]*dynamic.TCPRouter{
+						"default-test.route-673acf455cb2dab0b43a": {
+							EntryPoints: []string{"foo"},
+							Service:     "default-test.route-673acf455cb2dab0b43a",
+							Rule:        "HostSNI(`*`)",
+						},
+					},
+					Services: map[string]*dynamic.TCPService{
+						"default-test.route-673acf455cb2dab0b43a": {
+							Weighted: &dynamic.TCPWeightedRoundRobin{
+								Services: []dynamic.TCPWRRService{
+									{
+										Name:   "default-test.route-673acf455cb2dab0b43a-whoamitcp-ipv6-8080",
+										Weight: func(i int) *int { return &i }(1),
+									},
+									{
+										Name:   "default-test.route-673acf455cb2dab0b43a-external.service.with.ipv6-8080",
+										Weight: func(i int) *int { return &i }(1),
+									},
+								},
+							},
+						},
+						"default-test.route-673acf455cb2dab0b43a-whoamitcp-ipv6-8080": {
+							LoadBalancer: &dynamic.TCPServersLoadBalancer{
+								Servers: []dynamic.TCPServer{
+									{
+										Address: "[fd00:10:244:0:1::3]:8080",
+									},
+									{
+										Address: "[2001:db8:85a3:8d3:1319:8a2e:370:7348]:8080",
+									},
+								},
+							},
+						},
+						"default-test.route-673acf455cb2dab0b43a-external.service.with.ipv6-8080": {
+							LoadBalancer: &dynamic.TCPServersLoadBalancer{
+								Servers: []dynamic.TCPServer{
+									{
+										Address: "[fe80::200:5aee:feaa:20a2]:8080",
+									},
+								},
+							},
+						},
+					},
+				},
+				HTTP: &dynamic.HTTPConfiguration{
+					Routers: map[string]*dynamic.Router{
+						"default-test-route-6b204d94623b3df4370c": {
+							EntryPoints: []string{"foo"},
+							Service:     "default-test-route-6b204d94623b3df4370c",
+							Rule:        "Host(`foo.com`) && PathPrefix(`/bar`)",
+						},
+					},
+					Middlewares: map[string]*dynamic.Middleware{},
+					Services: map[string]*dynamic.Service{
+						"default-whoami-ipv6-8080": {
+							LoadBalancer: &dynamic.ServersLoadBalancer{
+								Servers: []dynamic.Server{
+									{
+										URL: "http://[2001:db8:85a3:8d3:1319:8a2e:370:7348]:8080",
+									},
+								},
+								PassHostHeader: func(i bool) *bool { return &i }(true),
+							},
+						},
+						"default-external-svc-with-ipv6-8080": {
+							LoadBalancer: &dynamic.ServersLoadBalancer{
+								Servers: []dynamic.Server{
+									{
+										URL: "http://[2001:db8:85a3:8d3:1319:8a2e:370:7347]:8080",
+									},
+								},
+								PassHostHeader: func(i bool) *bool { return &i }(true),
+							},
+						},
+						"default-test-route-6b204d94623b3df4370c": {
+							Weighted: &dynamic.WeightedRoundRobin{
+								Services: []dynamic.WRRService{
+									{
+										Name:   "default-whoami-ipv6-8080",
+										Weight: func(i int) *int { return &i }(1),
+									},
+									{
+										Name:   "default-external-svc-with-ipv6-8080",
+										Weight: func(i int) *int { return &i }(1),
+									},
+								},
+							},
+						},
+					},
+				},
+				TLS: &dynamic.TLSConfiguration{},
+			},
+		},
 	}
 
 	for _, test := range testCases {
diff --git a/pkg/provider/kubernetes/crd/kubernetes_udp.go b/pkg/provider/kubernetes/crd/kubernetes_udp.go
index 18d4f4b65..2d02c8b5f 100644
--- a/pkg/provider/kubernetes/crd/kubernetes_udp.go
+++ b/pkg/provider/kubernetes/crd/kubernetes_udp.go
@@ -4,6 +4,8 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"net"
+	"strconv"
 
 	"github.com/traefik/traefik/v2/pkg/config/dynamic"
 	"github.com/traefik/traefik/v2/pkg/log"
@@ -121,7 +123,7 @@ func loadUDPServers(client Client, namespace string, svc v1alpha1.ServiceUDP) ([
 	var servers []dynamic.UDPServer
 	if service.Spec.Type == corev1.ServiceTypeExternalName {
 		servers = append(servers, dynamic.UDPServer{
-			Address: fmt.Sprintf("%s:%d", service.Spec.ExternalName, portSpec.Port),
+			Address: net.JoinHostPort(service.Spec.ExternalName, strconv.Itoa(int(portSpec.Port))),
 		})
 	} else {
 		endpoints, endpointsExists, endpointsErr := client.GetEndpoints(namespace, svc.Name)
@@ -152,7 +154,7 @@ func loadUDPServers(client Client, namespace string, svc v1alpha1.ServiceUDP) ([
 
 			for _, addr := range subset.Addresses {
 				servers = append(servers, dynamic.UDPServer{
-					Address: fmt.Sprintf("%s:%d", addr.IP, port),
+					Address: net.JoinHostPort(addr.IP, strconv.Itoa(int(port))),
 				})
 			}
 		}
diff --git a/pkg/provider/kubernetes/ingress/fixtures/Ingress-with-IPv6-endpoints_endpoint.yml b/pkg/provider/kubernetes/ingress/fixtures/Ingress-with-IPv6-endpoints_endpoint.yml
new file mode 100644
index 000000000..e70dd1a13
--- /dev/null
+++ b/pkg/provider/kubernetes/ingress/fixtures/Ingress-with-IPv6-endpoints_endpoint.yml
@@ -0,0 +1,12 @@
+kind: Endpoints
+apiVersion: v1
+metadata:
+  name: service-bar
+  namespace: testing
+
+subsets:
+- addresses:
+  - ip: "2001:0db8:3c4d:0015:0000:0000:1a2f:1a2b"
+  ports:
+  - name: http
+    port: 8080
diff --git a/pkg/provider/kubernetes/ingress/fixtures/Ingress-with-IPv6-endpoints_ingress.yml b/pkg/provider/kubernetes/ingress/fixtures/Ingress-with-IPv6-endpoints_ingress.yml
new file mode 100644
index 000000000..a12baef74
--- /dev/null
+++ b/pkg/provider/kubernetes/ingress/fixtures/Ingress-with-IPv6-endpoints_ingress.yml
@@ -0,0 +1,18 @@
+kind: Ingress
+apiVersion: networking.k8s.io/v1beta1
+metadata:
+  name: example.com
+  namespace: testing
+
+spec:
+  rules:
+    - http:
+        paths:
+          - path: /bar
+            backend:
+              serviceName: service-bar
+              servicePort: 8080
+          - path: /foo
+            backend:
+              serviceName: service-foo
+              servicePort: 8080
diff --git a/pkg/provider/kubernetes/ingress/fixtures/Ingress-with-IPv6-endpoints_service.yml b/pkg/provider/kubernetes/ingress/fixtures/Ingress-with-IPv6-endpoints_service.yml
new file mode 100644
index 000000000..9b8bfdb8b
--- /dev/null
+++ b/pkg/provider/kubernetes/ingress/fixtures/Ingress-with-IPv6-endpoints_service.yml
@@ -0,0 +1,26 @@
+kind: Service
+apiVersion: v1
+metadata:
+  name: service-bar
+  namespace: testing
+
+spec:
+  ports:
+  - name: http
+    port: 8080
+  clusterIp: "fc00:f853:ccd:e793::1"
+  type: ClusterIP
+
+---
+kind: Service
+apiVersion: v1
+metadata:
+  name: service-foo
+  namespace: testing
+
+spec:
+  ports:
+  - name: http
+    port: 8080
+  type: ExternalName
+  externalName: "2001:0db8:3c4d:0015:0000:0000:1a2f:2a3b"
diff --git a/pkg/provider/kubernetes/ingress/kubernetes.go b/pkg/provider/kubernetes/ingress/kubernetes.go
index f5944edb1..8f06b214b 100644
--- a/pkg/provider/kubernetes/ingress/kubernetes.go
+++ b/pkg/provider/kubernetes/ingress/kubernetes.go
@@ -5,8 +5,10 @@ import (
 	"errors"
 	"fmt"
 	"math"
+	"net"
 	"os"
 	"sort"
+	"strconv"
 	"strings"
 	"time"
 
@@ -479,9 +481,10 @@ func loadService(client Client, namespace string, backend networkingv1beta1.Ingr
 
 	if service.Spec.Type == corev1.ServiceTypeExternalName {
 		protocol := getProtocol(portSpec, portSpec.Name, svcConfig)
+		hostPort := net.JoinHostPort(service.Spec.ExternalName, strconv.Itoa(int(portSpec.Port)))
 
 		svc.LoadBalancer.Servers = []dynamic.Server{
-			{URL: fmt.Sprintf("%s://%s:%d", protocol, service.Spec.ExternalName, portSpec.Port)},
+			{URL: fmt.Sprintf("%s://%s", protocol, hostPort)},
 		}
 
 		return svc, nil
@@ -516,8 +519,10 @@ func loadService(client Client, namespace string, backend networkingv1beta1.Ingr
 		protocol := getProtocol(portSpec, portName, svcConfig)
 
 		for _, addr := range subset.Addresses {
+			hostPort := net.JoinHostPort(addr.IP, strconv.Itoa(int(port)))
+
 			svc.LoadBalancer.Servers = append(svc.LoadBalancer.Servers, dynamic.Server{
-				URL: fmt.Sprintf("%s://%s:%d", protocol, addr.IP, port),
+				URL: fmt.Sprintf("%s://%s", protocol, hostPort),
 			})
 		}
 	}
diff --git a/pkg/provider/kubernetes/ingress/kubernetes_test.go b/pkg/provider/kubernetes/ingress/kubernetes_test.go
index 253b62f47..ee9c98347 100644
--- a/pkg/provider/kubernetes/ingress/kubernetes_test.go
+++ b/pkg/provider/kubernetes/ingress/kubernetes_test.go
@@ -661,6 +661,47 @@ func TestLoadConfigurationFromIngresses(t *testing.T) {
 				},
 			},
 		},
+		{
+			desc: "Ingress with IPv6 endpoints",
+			expected: &dynamic.Configuration{
+				TCP: &dynamic.TCPConfiguration{},
+				HTTP: &dynamic.HTTPConfiguration{
+					Middlewares: map[string]*dynamic.Middleware{},
+					Routers: map[string]*dynamic.Router{
+						"example-com-testing-bar": {
+							Rule:    "PathPrefix(`/bar`)",
+							Service: "testing-service-bar-8080",
+						},
+						"example-com-testing-foo": {
+							Rule:    "PathPrefix(`/foo`)",
+							Service: "testing-service-foo-8080",
+						},
+					},
+					Services: map[string]*dynamic.Service{
+						"testing-service-bar-8080": {
+							LoadBalancer: &dynamic.ServersLoadBalancer{
+								Servers: []dynamic.Server{
+									{
+										URL: "http://[2001:0db8:3c4d:0015:0000:0000:1a2f:1a2b]:8080",
+									},
+								},
+								PassHostHeader: Bool(true),
+							},
+						},
+						"testing-service-foo-8080": {
+							LoadBalancer: &dynamic.ServersLoadBalancer{
+								Servers: []dynamic.Server{
+									{
+										URL: "http://[2001:0db8:3c4d:0015:0000:0000:1a2f:2a3b]:8080",
+									},
+								},
+								PassHostHeader: Bool(true),
+							},
+						},
+					},
+				},
+			},
+		},
 		{
 			desc: "TLS support",
 			expected: &dynamic.Configuration{

From 134a767a7f22fc3835e69751b9a17e3b09c73264 Mon Sep 17 00:00:00 2001
From: Ludovic Fernandez <ldez@users.noreply.github.com>
Date: Fri, 4 Dec 2020 23:40:03 +0100
Subject: [PATCH 09/14] Update go-acme/lego to v4.1.3

---
 go.mod | 2 +-
 go.sum | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/go.mod b/go.mod
index 76298aa9f..ccf24f391 100644
--- a/go.mod
+++ b/go.mod
@@ -35,7 +35,7 @@ require (
 	github.com/fatih/structs v1.1.0
 	github.com/flynn/go-shlex v0.0.0-20150515145356-3f9db97f8568 // indirect
 	github.com/gambol99/go-marathon v0.0.0-20180614232016-99a156b96fb2
-	github.com/go-acme/lego/v4 v4.1.2
+	github.com/go-acme/lego/v4 v4.1.3
 	github.com/go-check/check v0.0.0-00010101000000-000000000000
 	github.com/go-kit/kit v0.10.1-0.20200915143503-439c4d2ed3ea
 	github.com/golang/protobuf v1.3.4
diff --git a/go.sum b/go.sum
index eec9c67e5..c6b5724d1 100644
--- a/go.sum
+++ b/go.sum
@@ -275,8 +275,8 @@ github.com/gambol99/go-marathon v0.0.0-20180614232016-99a156b96fb2/go.mod h1:GLy
 github.com/ghodss/yaml v0.0.0-20150909031657-73d445a93680/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
 github.com/ghodss/yaml v1.0.0 h1:wQHKEahhL6wmXdzwWG11gIVCkOv05bNOh+Rxn0yngAk=
 github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
-github.com/go-acme/lego/v4 v4.1.2 h1:1zROppXkTbAIh7J7AydGD3dFICLIocucJY1NTH/wB64=
-github.com/go-acme/lego/v4 v4.1.2/go.mod h1:pIFm5tWkXSgiAEfJ/XQCQIvX1cEvHFwbgLZyx8OVSUE=
+github.com/go-acme/lego/v4 v4.1.3 h1:D8nnzrijQFUAqdNPwnbvm6tJ3AJAzQAlnROeecUNG/4=
+github.com/go-acme/lego/v4 v4.1.3/go.mod h1:pIFm5tWkXSgiAEfJ/XQCQIvX1cEvHFwbgLZyx8OVSUE=
 github.com/go-cmd/cmd v1.0.5/go.mod h1:y8q8qlK5wQibcw63djSl/ntiHUHXHGdCkPk0j4QeW4s=
 github.com/go-errors/errors v1.0.1 h1:LUHzmkK3GUKUrL/1gfBUxAHzcev3apQlezX/+O7ma6w=
 github.com/go-errors/errors v1.0.1/go.mod h1:f4zRHt4oKfwPJE5k8C9vpYG+aDHdBFUsgrm6/TyX73Q=

From 0d15ac8861e81059a5da651d95ef5a433593ad2f Mon Sep 17 00:00:00 2001
From: Ioannis Pinakoulakis <ipinak@users.noreply.github.com>
Date: Mon, 7 Dec 2020 15:14:03 +0200
Subject: [PATCH 10/14] Fix UI bug on long service name

---
 webui/src/components/_commons/PanelMiddlewares.vue     |  3 ++-
 .../src/components/_commons/PanelMirroringServices.vue |  3 ++-
 webui/src/components/_commons/PanelRouterDetails.vue   |  3 ++-
 .../src/components/_commons/PanelWeightedServices.vue  |  3 ++-
 webui/src/css/sass/app.scss                            | 10 ++++++++++
 5 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/webui/src/components/_commons/PanelMiddlewares.vue b/webui/src/components/_commons/PanelMiddlewares.vue
index daab41a76..266a12f16 100644
--- a/webui/src/components/_commons/PanelMiddlewares.vue
+++ b/webui/src/components/_commons/PanelMiddlewares.vue
@@ -231,8 +231,9 @@
               <div class="text-subtitle2">Service</div>
               <q-chip
                 dense
-                class="app-chip app-chip-green">
+                class="app-chip app-chip-green app-chip-overflow">
                 {{ exData(middleware).service }}
+                <q-tooltip>{{ exData(middleware).service }}</q-tooltip>
               </q-chip>
             </div>
           </div>
diff --git a/webui/src/components/_commons/PanelMirroringServices.vue b/webui/src/components/_commons/PanelMirroringServices.vue
index f9b505408..09a613894 100644
--- a/webui/src/components/_commons/PanelMirroringServices.vue
+++ b/webui/src/components/_commons/PanelMirroringServices.vue
@@ -21,8 +21,9 @@
             <div class="col-6">
               <q-chip
                 dense
-                class="app-chip app-chip-rule">
+                class="app-chip app-chip-rule app-chip-overflow">
                 {{ service.name }}
+                <q-tooltip>{{service.name}}</q-tooltip>
               </q-chip>
             </div>
             <div class="col-3 text-right">
diff --git a/webui/src/components/_commons/PanelRouterDetails.vue b/webui/src/components/_commons/PanelRouterDetails.vue
index cb53987ce..26ddfc6f3 100644
--- a/webui/src/components/_commons/PanelRouterDetails.vue
+++ b/webui/src/components/_commons/PanelRouterDetails.vue
@@ -66,8 +66,9 @@
               dense
               clickable
               @click.native="$router.push({ path: `/${protocol}/services/${getServiceId()}`})"
-              class="app-chip app-chip-wrap app-chip-service">
+              class="app-chip app-chip-wrap app-chip-service app-chip-overflow">
               {{ data.service }}
+              <q-tooltip>{{ data.service }}</q-tooltip>
             </q-chip>
           </div>
         </div>
diff --git a/webui/src/components/_commons/PanelWeightedServices.vue b/webui/src/components/_commons/PanelWeightedServices.vue
index 6cf5784c0..fb0ec582c 100644
--- a/webui/src/components/_commons/PanelWeightedServices.vue
+++ b/webui/src/components/_commons/PanelWeightedServices.vue
@@ -21,8 +21,9 @@
             <div class="col-7">
               <q-chip
                 dense
-                class="app-chip app-chip-rule">
+                class="app-chip app-chip-rule app-chip-overflow">
                 {{ service.name }}
+                <q-tooltip>{{service.name}}</q-tooltip>
               </q-chip>
             </div>
             <div class="col-3">
diff --git a/webui/src/css/sass/app.scss b/webui/src/css/sass/app.scss
index f9ab3e5a9..0bdc9ba3b 100644
--- a/webui/src/css/sass/app.scss
+++ b/webui/src/css/sass/app.scss
@@ -131,6 +131,16 @@ body {
       white-space: normal;
     }
   }
+  &-overflow {
+    max-width: 90%;
+
+    .q-chip__content{
+      display: block;
+      white-space: nowrap;
+      overflow: hidden;
+      text-overflow: ellipsis;
+    }
+  }
   &-accent, &-rule {
     color: $accent;
     background-color: rgba($accent, 0.1);

From 02d856b8a5da96bd145cb043161e07d8aa5475db Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Paulo=20J=C3=BAnior?= <paulo@containo.us>
Date: Mon, 7 Dec 2020 14:24:04 -0300
Subject: [PATCH 11/14] Documentation: Add spacing to sidebars so the last item
 is always visible

---
 docs/content/assets/styles/menu.css | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/docs/content/assets/styles/menu.css b/docs/content/assets/styles/menu.css
index da46bae00..6cdcfa870 100644
--- a/docs/content/assets/styles/menu.css
+++ b/docs/content/assets/styles/menu.css
@@ -35,6 +35,10 @@
   padding: 0;
 }
 
+.md-sidebar__scrollwrap {
+  max-height: calc(100% - 50px);
+}
+
 .md-sidebar--secondary .md-sidebar__scrollwrap {
   border-radius: 8px;
   background-color: var(--light-blue) !important;

From c72769e2ea077332f982c4b1ef38c6b111e9998b Mon Sep 17 00:00:00 2001
From: Harold Ozouf <harold.ozouf@gmail.com>
Date: Wed, 9 Dec 2020 14:16:03 +0100
Subject: [PATCH 12/14] Fix TLS options fallback when domain and options are
 the same

Co-authored-by: Kevin Pollet <pollet.kevin@gmail.com>
---
 pkg/server/router/tcp/router.go      |  54 +++--
 pkg/server/router/tcp/router_test.go | 323 +++++++++++++++++++++++++--
 2 files changed, 328 insertions(+), 49 deletions(-)

diff --git a/pkg/server/router/tcp/router.go b/pkg/server/router/tcp/router.go
index ed8bc8ff9..69a04fc4f 100644
--- a/pkg/server/router/tcp/router.go
+++ b/pkg/server/router/tcp/router.go
@@ -109,13 +109,18 @@ func (m *Manager) buildEntryPointHandler(ctx context.Context, configs map[string
 	tlsOptionsForHostSNI := map[string]map[string]nameAndConfig{}
 	tlsOptionsForHost := map[string]string{}
 	for routerHTTPName, routerHTTPConfig := range configsHTTP {
-		if len(routerHTTPConfig.TLS.Options) == 0 || routerHTTPConfig.TLS.Options == defaultTLSConfigName {
+		if routerHTTPConfig.TLS == nil {
 			continue
 		}
 
 		ctxRouter := log.With(provider.AddInContext(ctx, routerHTTPName), log.Str(log.RouterName, routerHTTPName))
 		logger := log.FromContext(ctxRouter)
 
+		tlsOptionsName := defaultTLSConfigName
+		if len(routerHTTPConfig.TLS.Options) > 0 && routerHTTPConfig.TLS.Options != defaultTLSConfigName {
+			tlsOptionsName = provider.GetQualifiedName(ctxRouter, routerHTTPConfig.TLS.Options)
+		}
+
 		domains, err := rules.ParseDomains(routerHTTPConfig.Rule)
 		if err != nil {
 			routerErr := fmt.Errorf("invalid rule %s, error: %w", routerHTTPConfig.Rule, err)
@@ -129,34 +134,27 @@ func (m *Manager) buildEntryPointHandler(ctx context.Context, configs map[string
 		}
 
 		for _, domain := range domains {
-			if routerHTTPConfig.TLS != nil {
-				tlsOptionsName := routerHTTPConfig.TLS.Options
-				if tlsOptionsName != defaultTLSConfigName {
-					tlsOptionsName = provider.GetQualifiedName(ctxRouter, routerHTTPConfig.TLS.Options)
-				}
+			tlsConf, err := m.tlsManager.Get(defaultTLSStoreName, tlsOptionsName)
+			if err != nil {
+				routerHTTPConfig.AddError(err, true)
+				logger.Debug(err)
+				continue
+			}
 
-				tlsConf, err := m.tlsManager.Get(defaultTLSStoreName, tlsOptionsName)
-				if err != nil {
-					routerHTTPConfig.AddError(err, true)
-					logger.Debug(err)
-					continue
-				}
+			// domain is already in lower case thanks to the domain parsing
+			if tlsOptionsForHostSNI[domain] == nil {
+				tlsOptionsForHostSNI[domain] = make(map[string]nameAndConfig)
+			}
+			tlsOptionsForHostSNI[domain][tlsOptionsName] = nameAndConfig{
+				routerName: routerHTTPName,
+				TLSConfig:  tlsConf,
+			}
 
-				// domain is already in lower case thanks to the domain parsing
-				if tlsOptionsForHostSNI[domain] == nil {
-					tlsOptionsForHostSNI[domain] = make(map[string]nameAndConfig)
-				}
-				tlsOptionsForHostSNI[domain][routerHTTPConfig.TLS.Options] = nameAndConfig{
-					routerName: routerHTTPName,
-					TLSConfig:  tlsConf,
-				}
-
-				if _, ok := tlsOptionsForHost[domain]; ok {
-					// Multiple tlsOptions fallback to default
-					tlsOptionsForHost[domain] = "default"
-				} else {
-					tlsOptionsForHost[domain] = routerHTTPConfig.TLS.Options
-				}
+			if name, ok := tlsOptionsForHost[domain]; ok && name != tlsOptionsName {
+				// Different tlsOptions on the same domain fallback to default
+				tlsOptionsForHost[domain] = defaultTLSConfigName
+			} else {
+				tlsOptionsForHost[domain] = tlsOptionsName
 			}
 		}
 	}
@@ -304,5 +302,5 @@ func findTLSOptionName(tlsOptionsForHost map[string]string, host string) string
 		return tlsOptions
 	}
 
-	return "default"
+	return defaultTLSConfigName
 }
diff --git a/pkg/server/router/tcp/router_test.go b/pkg/server/router/tcp/router_test.go
index 6a966b79d..a00465a86 100644
--- a/pkg/server/router/tcp/router_test.go
+++ b/pkg/server/router/tcp/router_test.go
@@ -2,25 +2,31 @@ package tcp
 
 import (
 	"context"
+	"crypto/tls"
+	"net/http"
+	"net/http/httptest"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"github.com/traefik/traefik/v2/pkg/config/dynamic"
 	"github.com/traefik/traefik/v2/pkg/config/runtime"
 	"github.com/traefik/traefik/v2/pkg/server/service/tcp"
-	"github.com/traefik/traefik/v2/pkg/tls"
+	traefiktls "github.com/traefik/traefik/v2/pkg/tls"
 )
 
 func TestRuntimeConfiguration(t *testing.T) {
 	testCases := []struct {
-		desc          string
-		serviceConfig map[string]*runtime.TCPServiceInfo
-		routerConfig  map[string]*runtime.TCPRouterInfo
-		expectedError int
+		desc              string
+		httpServiceConfig map[string]*runtime.ServiceInfo
+		httpRouterConfig  map[string]*runtime.RouterInfo
+		tcpServiceConfig  map[string]*runtime.TCPServiceInfo
+		tcpRouterConfig   map[string]*runtime.TCPRouterInfo
+		expectedError     int
 	}{
 		{
 			desc: "No error",
-			serviceConfig: map[string]*runtime.TCPServiceInfo{
+			tcpServiceConfig: map[string]*runtime.TCPServiceInfo{
 				"foo-service": {
 					TCPService: &dynamic.TCPService{
 						LoadBalancer: &dynamic.TCPServersLoadBalancer{
@@ -38,7 +44,7 @@ func TestRuntimeConfiguration(t *testing.T) {
 					},
 				},
 			},
-			routerConfig: map[string]*runtime.TCPRouterInfo{
+			tcpRouterConfig: map[string]*runtime.TCPRouterInfo{
 				"foo": {
 					TCPRouter: &dynamic.TCPRouter{
 						EntryPoints: []string{"web"},
@@ -65,9 +71,54 @@ func TestRuntimeConfiguration(t *testing.T) {
 			},
 			expectedError: 0,
 		},
+		{
+			desc: "HTTP routers with same domain but different TLS options",
+			httpServiceConfig: map[string]*runtime.ServiceInfo{
+				"foo-service": {
+					Service: &dynamic.Service{
+						LoadBalancer: &dynamic.ServersLoadBalancer{
+							Servers: []dynamic.Server{
+								{
+									Port: "8085",
+									URL:  "127.0.0.1:8085",
+								},
+								{
+									URL:  "127.0.0.1:8086",
+									Port: "8086",
+								},
+							},
+						},
+					},
+				},
+			},
+			httpRouterConfig: map[string]*runtime.RouterInfo{
+				"foo": {
+					Router: &dynamic.Router{
+						EntryPoints: []string{"web"},
+						Service:     "foo-service",
+						Rule:        "Host(`bar.foo`)",
+						TLS: &dynamic.RouterTLSConfig{
+							Options: "foo",
+						},
+					},
+				},
+				"bar": {
+					Router: &dynamic.Router{
+
+						EntryPoints: []string{"web"},
+						Service:     "foo-service",
+						Rule:        "Host(`bar.foo`) && PathPrefix(`/path`)",
+						TLS: &dynamic.RouterTLSConfig{
+							Options: "bar",
+						},
+					},
+				},
+			},
+			expectedError: 2,
+		},
 		{
 			desc: "One router with wrong rule",
-			serviceConfig: map[string]*runtime.TCPServiceInfo{
+			tcpServiceConfig: map[string]*runtime.TCPServiceInfo{
 				"foo-service": {
 					TCPService: &dynamic.TCPService{
 						LoadBalancer: &dynamic.TCPServersLoadBalancer{
@@ -80,7 +131,7 @@ func TestRuntimeConfiguration(t *testing.T) {
 					},
 				},
 			},
-			routerConfig: map[string]*runtime.TCPRouterInfo{
+			tcpRouterConfig: map[string]*runtime.TCPRouterInfo{
 				"foo": {
 					TCPRouter: &dynamic.TCPRouter{
 						EntryPoints: []string{"web"},
@@ -101,7 +152,7 @@ func TestRuntimeConfiguration(t *testing.T) {
 		},
 		{
 			desc: "All router with wrong rule",
-			serviceConfig: map[string]*runtime.TCPServiceInfo{
+			tcpServiceConfig: map[string]*runtime.TCPServiceInfo{
 				"foo-service": {
 					TCPService: &dynamic.TCPService{
 						LoadBalancer: &dynamic.TCPServersLoadBalancer{
@@ -114,7 +165,7 @@ func TestRuntimeConfiguration(t *testing.T) {
 					},
 				},
 			},
-			routerConfig: map[string]*runtime.TCPRouterInfo{
+			tcpRouterConfig: map[string]*runtime.TCPRouterInfo{
 				"foo": {
 					TCPRouter: &dynamic.TCPRouter{
 						EntryPoints: []string{"web"},
@@ -134,7 +185,7 @@ func TestRuntimeConfiguration(t *testing.T) {
 		},
 		{
 			desc: "Router with unknown service",
-			serviceConfig: map[string]*runtime.TCPServiceInfo{
+			tcpServiceConfig: map[string]*runtime.TCPServiceInfo{
 				"foo-service": {
 					TCPService: &dynamic.TCPService{
 						LoadBalancer: &dynamic.TCPServersLoadBalancer{
@@ -147,7 +198,7 @@ func TestRuntimeConfiguration(t *testing.T) {
 					},
 				},
 			},
-			routerConfig: map[string]*runtime.TCPRouterInfo{
+			tcpRouterConfig: map[string]*runtime.TCPRouterInfo{
 				"foo": {
 					TCPRouter: &dynamic.TCPRouter{
 						EntryPoints: []string{"web"},
@@ -168,14 +219,14 @@ func TestRuntimeConfiguration(t *testing.T) {
 		},
 		{
 			desc: "Router with broken service",
-			serviceConfig: map[string]*runtime.TCPServiceInfo{
+			tcpServiceConfig: map[string]*runtime.TCPServiceInfo{
 				"foo-service": {
 					TCPService: &dynamic.TCPService{
 						LoadBalancer: nil,
 					},
 				},
 			},
-			routerConfig: map[string]*runtime.TCPRouterInfo{
+			tcpRouterConfig: map[string]*runtime.TCPRouterInfo{
 				"bar": {
 					TCPRouter: &dynamic.TCPRouter{
 						EntryPoints: []string{"web"},
@@ -197,15 +248,17 @@ func TestRuntimeConfiguration(t *testing.T) {
 			entryPoints := []string{"web"}
 
 			conf := &runtime.Configuration{
-				TCPServices: test.serviceConfig,
-				TCPRouters:  test.routerConfig,
+				Services:    test.httpServiceConfig,
+				Routers:     test.httpRouterConfig,
+				TCPServices: test.tcpServiceConfig,
+				TCPRouters:  test.tcpRouterConfig,
 			}
 			serviceManager := tcp.NewManager(conf)
-			tlsManager := tls.NewManager()
+			tlsManager := traefiktls.NewManager()
 			tlsManager.UpdateConfigs(
 				context.Background(),
-				map[string]tls.Store{},
-				map[string]tls.Options{
+				map[string]traefiktls.Store{},
+				map[string]traefiktls.Options{
 					"default": {
 						MinVersion: "VersionTLS10",
 					},
@@ -216,7 +269,7 @@ func TestRuntimeConfiguration(t *testing.T) {
 						MinVersion: "VersionTLS11",
 					},
 				},
-				[]*tls.CertAndStores{})
+				[]*traefiktls.CertAndStores{})
 
 			routerManager := NewManager(conf, serviceManager,
 				nil, nil, tlsManager)
@@ -237,7 +290,235 @@ func TestRuntimeConfiguration(t *testing.T) {
 					allErrors++
 				}
 			}
+			for _, v := range conf.Services {
+				if v.Err != nil {
+					allErrors++
+				}
+			}
+			for _, v := range conf.Routers {
+				if len(v.Err) > 0 {
+					allErrors++
+				}
+			}
 			assert.Equal(t, test.expectedError, allErrors)
 		})
 	}
 }
+
+func TestDomainFronting(t *testing.T) {
+	tests := []struct {
+		desc           string
+		routers        map[string]*runtime.RouterInfo
+		expectedStatus int
+	}{
+		{
+			desc: "Request is misdirected when TLS options are different",
+			routers: map[string]*runtime.RouterInfo{
+				"router-1@file": {
+					Router: &dynamic.Router{
+						EntryPoints: []string{"web"},
+						Rule:        "Host(`host1.local`)",
+						TLS: &dynamic.RouterTLSConfig{
+							Options: "host1",
+						},
+					},
+				},
+				"router-2@file": {
+					Router: &dynamic.Router{
+						EntryPoints: []string{"web"},
+						Rule:        "Host(`host2.local`)",
+						TLS:         &dynamic.RouterTLSConfig{},
+					},
+				},
+			},
+			expectedStatus: http.StatusMisdirectedRequest,
+		},
+		{
+			desc: "Request is OK when TLS options are the same",
+			routers: map[string]*runtime.RouterInfo{
+				"router-1@file": {
+					Router: &dynamic.Router{
+						EntryPoints: []string{"web"},
+						Rule:        "Host(`host1.local`)",
+						TLS: &dynamic.RouterTLSConfig{
+							Options: "host1",
+						},
+					},
+				},
+				"router-2@file": {
+					Router: &dynamic.Router{
+						EntryPoints: []string{"web"},
+						Rule:        "Host(`host2.local`)",
+						TLS: &dynamic.RouterTLSConfig{
+							Options: "host1",
+						},
+					},
+				},
+			},
+			expectedStatus: http.StatusOK,
+		},
+		{
+			desc: "Default TLS options is used when options are ambiguous for the same host",
+			routers: map[string]*runtime.RouterInfo{
+				"router-1@file": {
+					Router: &dynamic.Router{
+						EntryPoints: []string{"web"},
+						Rule:        "Host(`host1.local`)",
+						TLS: &dynamic.RouterTLSConfig{
+							Options: "host1",
+						},
+					},
+				},
+				"router-2@file": {
+					Router: &dynamic.Router{
+						EntryPoints: []string{"web"},
+						Rule:        "Host(`host1.local`) && PathPrefix(`/foo`)",
+						TLS: &dynamic.RouterTLSConfig{
+							Options: "default",
+						},
+					},
+				},
+				"router-3@file": {
+					Router: &dynamic.Router{
+						EntryPoints: []string{"web"},
+						Rule:        "Host(`host2.local`)",
+						TLS: &dynamic.RouterTLSConfig{
+							Options: "host1",
+						},
+					},
+				},
+			},
+			expectedStatus: http.StatusMisdirectedRequest,
+		},
+		{
+			desc: "Default TLS options should not be used when options are the same for the same host",
+			routers: map[string]*runtime.RouterInfo{
+				"router-1@file": {
+					Router: &dynamic.Router{
+						EntryPoints: []string{"web"},
+						Rule:        "Host(`host1.local`)",
+						TLS: &dynamic.RouterTLSConfig{
+							Options: "host1",
+						},
+					},
+				},
+				"router-2@file": {
+					Router: &dynamic.Router{
+						EntryPoints: []string{"web"},
+						Rule:        "Host(`host1.local`) && PathPrefix(`/bar`)",
+						TLS: &dynamic.RouterTLSConfig{
+							Options: "host1",
+						},
+					},
+				},
+				"router-3@file": {
+					Router: &dynamic.Router{
+						EntryPoints: []string{"web"},
+						Rule:        "Host(`host2.local`)",
+						TLS: &dynamic.RouterTLSConfig{
+							Options: "host1",
+						},
+					},
+				},
+			},
+			expectedStatus: http.StatusOK,
+		},
+		{
+			desc: "Request is misdirected when TLS options have the same name but from different providers",
+			routers: map[string]*runtime.RouterInfo{
+				"router-1@file": {
+					Router: &dynamic.Router{
+						EntryPoints: []string{"web"},
+						Rule:        "Host(`host1.local`)",
+						TLS: &dynamic.RouterTLSConfig{
+							Options: "host1",
+						},
+					},
+				},
+				"router-2@crd": {
+					Router: &dynamic.Router{
+						EntryPoints: []string{"web"},
+						Rule:        "Host(`host2.local`)",
+						TLS: &dynamic.RouterTLSConfig{
+							Options: "host1",
+						},
+					},
+				},
+			},
+			expectedStatus: http.StatusMisdirectedRequest,
+		},
+		{
+			desc: "Request is OK when TLS options reference from a different provider is the same",
+			routers: map[string]*runtime.RouterInfo{
+				"router-1@file": {
+					Router: &dynamic.Router{
+						EntryPoints: []string{"web"},
+						Rule:        "Host(`host1.local`)",
+						TLS: &dynamic.RouterTLSConfig{
+							Options: "host1@crd",
+						},
+					},
+				},
+				"router-2@crd": {
+					Router: &dynamic.Router{
+						EntryPoints: []string{"web"},
+						Rule:        "Host(`host2.local`)",
+						TLS: &dynamic.RouterTLSConfig{
+							Options: "host1@crd",
+						},
+					},
+				},
+			},
+			expectedStatus: http.StatusOK,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.desc, func(t *testing.T) {
+			entryPoints := []string{"web"}
+			tlsOptions := map[string]traefiktls.Options{
+				"default": {
+					MinVersion: "VersionTLS10",
+				},
+				"host1@file": {
+					MinVersion: "VersionTLS12",
+				},
+				"host1@crd": {
+					MinVersion: "VersionTLS12",
+				},
+			}
+
+			conf := &runtime.Configuration{
+				Routers: test.routers,
+			}
+
+			serviceManager := tcp.NewManager(conf)
+
+			tlsManager := traefiktls.NewManager()
+			tlsManager.UpdateConfigs(context.Background(), map[string]traefiktls.Store{}, tlsOptions, []*traefiktls.CertAndStores{})
+
+			httpsHandler := map[string]http.Handler{
+				"web": http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {}),
+			}
+
+			routerManager := NewManager(conf, serviceManager, nil, httpsHandler, tlsManager)
+
+			routers := routerManager.BuildHandlers(context.Background(), entryPoints)
+
+			router, ok := routers["web"]
+			require.True(t, ok)
+
+			req := httptest.NewRequest(http.MethodGet, "/", nil)
+			req.Host = "host1.local"
+			req.TLS = &tls.ConnectionState{
+				ServerName: "host2.local",
+			}
+
+			rw := httptest.NewRecorder()
+
+			router.GetHTTPSHandler().ServeHTTP(rw, req)
+
+			assert.Equal(t, test.expectedStatus, rw.Code)
+		})
+	}
+}

From 7ba907f261b4cedfc82d06c4a3a5a37ce819e889 Mon Sep 17 00:00:00 2001
From: Romain <rtribotte@users.noreply.github.com>
Date: Thu, 10 Dec 2020 14:58:04 +0100
Subject: [PATCH 13/14] IngressRoute: add an option to disable cross-namespace
 routing

Co-authored-by: Jean-Baptiste Doumenjou <925513+jbdoumenjou@users.noreply.github.com>
---
 docs/content/providers/kubernetes-crd.md      |  28 +
 .../reference/static-configuration/cli-ref.md |   3 +
 .../reference/static-configuration/env-ref.md |   3 +
 .../reference/static-configuration/file.toml  |   1 +
 .../reference/static-configuration/file.yaml  |   1 +
 .../k8s/07-ingressroute-cross-namespace.yml   | 120 ++++
 integration/fixtures/k8s_crd.toml             |   1 +
 integration/k8s_test.go                       |   1 +
 integration/testdata/rawdata-crd.json         |  33 +
 .../kubernetes/crd/fixtures/services.yml      |  30 +
 .../kubernetes/crd/fixtures/tcp/services.yml  |  30 +
 .../crd/fixtures/tcp/with_cross_namespace.yml |  16 +
 .../kubernetes/crd/fixtures/udp/services.yml  |  30 +
 .../crd/fixtures/udp/with_cross_namespace.yml |  15 +
 .../crd/fixtures/with_cross_namespace.yml     |  91 +++
 .../with_middleware_cross_namespace.yml       |  58 ++
 pkg/provider/kubernetes/crd/kubernetes.go     |  23 +-
 .../kubernetes/crd/kubernetes_http.go         |  72 ++-
 pkg/provider/kubernetes/crd/kubernetes_tcp.go |  10 +-
 .../kubernetes/crd/kubernetes_test.go         | 583 +++++++++++++++++-
 pkg/provider/kubernetes/crd/kubernetes_udp.go |  10 +-
 21 files changed, 1123 insertions(+), 36 deletions(-)
 create mode 100644 integration/fixtures/k8s/07-ingressroute-cross-namespace.yml
 create mode 100644 pkg/provider/kubernetes/crd/fixtures/tcp/with_cross_namespace.yml
 create mode 100644 pkg/provider/kubernetes/crd/fixtures/udp/with_cross_namespace.yml
 create mode 100644 pkg/provider/kubernetes/crd/fixtures/with_cross_namespace.yml
 create mode 100644 pkg/provider/kubernetes/crd/fixtures/with_middleware_cross_namespace.yml

diff --git a/docs/content/providers/kubernetes-crd.md b/docs/content/providers/kubernetes-crd.md
index 41a6c5b89..8f2e6cfe5 100644
--- a/docs/content/providers/kubernetes-crd.md
+++ b/docs/content/providers/kubernetes-crd.md
@@ -250,6 +250,34 @@ providers:
 --providers.kubernetescrd.throttleDuration=10s
 ```
 
+### `allowCrossNamespace`
+
+_Optional, Default: true_
+
+```toml tab="File (TOML)"
+[providers.kubernetesCRD]
+  allowCrossNamespace = false
+  # ...
+```
+
+```yaml tab="File (YAML)"
+providers:
+  kubernetesCRD:
+    allowCrossNamespace: false
+    # ...
+```
+
+```bash tab="CLI"
+--providers.kubernetescrd.allowCrossNamespace=false
+```
+
+If the parameter is set to `false`, an IngressRoute will not be able to reference any resources
+in another namespace than the IngressRoute namespace.
+
+!!! warning "Deprecation"
+    
+    Please notice that the default value for this option will be set to `false` in a future version.
+
 ## Further
 
 Also see the [full example](../user-guides/crd-acme/index.md) with Let's Encrypt.
diff --git a/docs/content/reference/static-configuration/cli-ref.md b/docs/content/reference/static-configuration/cli-ref.md
index 8ecd20175..f5ad7077b 100644
--- a/docs/content/reference/static-configuration/cli-ref.md
+++ b/docs/content/reference/static-configuration/cli-ref.md
@@ -540,6 +540,9 @@ TLS key
 `--providers.kubernetescrd`:  
 Enable Kubernetes backend with default settings. (Default: ```false```)
 
+`--providers.kubernetescrd.allowcrossnamespace`:  
+Allow cross namespace resource reference. (Default: ```true```)
+
 `--providers.kubernetescrd.certauthfilepath`:  
 Kubernetes certificate authority file path (not needed for in-cluster client).
 
diff --git a/docs/content/reference/static-configuration/env-ref.md b/docs/content/reference/static-configuration/env-ref.md
index 83c5e8480..9abff68d3 100644
--- a/docs/content/reference/static-configuration/env-ref.md
+++ b/docs/content/reference/static-configuration/env-ref.md
@@ -540,6 +540,9 @@ TLS key
 `TRAEFIK_PROVIDERS_KUBERNETESCRD`:  
 Enable Kubernetes backend with default settings. (Default: ```false```)
 
+`TRAEFIK_PROVIDERS_KUBERNETESCRD_ALLOWCROSSNAMESPACE`:  
+Allow cross namespace resource reference. (Default: ```true```)
+
 `TRAEFIK_PROVIDERS_KUBERNETESCRD_CERTAUTHFILEPATH`:  
 Kubernetes certificate authority file path (not needed for in-cluster client).
 
diff --git a/docs/content/reference/static-configuration/file.toml b/docs/content/reference/static-configuration/file.toml
index 8bef7d6ac..1d5985d19 100644
--- a/docs/content/reference/static-configuration/file.toml
+++ b/docs/content/reference/static-configuration/file.toml
@@ -113,6 +113,7 @@
     certAuthFilePath = "foobar"
     disablePassHostHeaders = true
     namespaces = ["foobar", "foobar"]
+    allowCrossNamespace = true
     labelSelector = "foobar"
     ingressClass = "foobar"
     throttleDuration = 42
diff --git a/docs/content/reference/static-configuration/file.yaml b/docs/content/reference/static-configuration/file.yaml
index 9da38a70a..26332ef18 100644
--- a/docs/content/reference/static-configuration/file.yaml
+++ b/docs/content/reference/static-configuration/file.yaml
@@ -123,6 +123,7 @@ providers:
     namespaces:
     - foobar
     - foobar
+    allowCrossNamespace: true
     labelSelector: foobar
     ingressClass: foobar
     throttleDuration: 42s
diff --git a/integration/fixtures/k8s/07-ingressroute-cross-namespace.yml b/integration/fixtures/k8s/07-ingressroute-cross-namespace.yml
new file mode 100644
index 000000000..fbdeb88a4
--- /dev/null
+++ b/integration/fixtures/k8s/07-ingressroute-cross-namespace.yml
@@ -0,0 +1,120 @@
+---
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: other-ns
+
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: whoami
+  namespace: other-ns
+
+spec:
+  ports:
+    - name: http
+      port: 80
+  selector:
+    app: traefiklabs
+    task: whoami
+
+---
+apiVersion: traefik.containo.us/v1alpha1
+kind: IngressRoute
+metadata:
+  name: test6.route
+  namespace: other-ns
+
+spec:
+  entryPoints:
+    - web
+  routes:
+  - match: Host(`foo.com`) && PathPrefix(`/a`)
+    kind: Rule
+    services:
+    - name: whoami
+      namespace: default
+      port: 80
+  - match: Host(`foo.com`) && PathPrefix(`/b`)
+    kind: Rule
+    services:
+    - name: wrr2
+      namespace: default
+      kind: TraefikService
+  - match: Host(`foo.com`) && PathPrefix(`/c`)
+    kind: Rule
+    services:
+    - name: wrr3
+      kind: TraefikService
+  - match: Host(`foo.com`) && PathPrefix(`/d`)
+    kind: Rule
+    services:
+    - name: whoami
+      namespace: other-ns
+      port: 80
+    middlewares:
+    - name: stripprefix2
+      namespace: default
+  - match: Host(`foo.com`) && PathPrefix(`/e`)
+    kind: Rule
+    services:
+    - name: whoami
+      port: 80
+    middlewares:
+    - name: test-errorpage
+
+---
+apiVersion: traefik.containo.us/v1alpha1
+kind: TraefikService
+metadata:
+  name: wrr2
+  namespace: default
+
+spec:
+  weighted:
+    services:
+      - name: whoami
+        port: 80
+
+---
+apiVersion: traefik.containo.us/v1alpha1
+kind: TraefikService
+metadata:
+  name: wrr3
+  namespace: other-ns
+
+spec:
+  weighted:
+    services:
+      - name: whoami
+        namespace: default
+        port: 80
+
+---
+apiVersion: traefik.containo.us/v1alpha1
+kind: Middleware
+metadata:
+  name: stripprefix2
+  namespace: default
+
+spec:
+  stripPrefix:
+    prefixes:
+      - /tobestripped
+
+---
+apiVersion: traefik.containo.us/v1alpha1
+kind: Middleware
+metadata:
+  name: test-errorpage
+
+spec:
+  errors:
+    status:
+      - 500-599
+    query: /{status}.html
+    service:
+      name: whoami
+      namespace: other-ns
+      port: 80
diff --git a/integration/fixtures/k8s_crd.toml b/integration/fixtures/k8s_crd.toml
index 1f85c7822..3015b6093 100644
--- a/integration/fixtures/k8s_crd.toml
+++ b/integration/fixtures/k8s_crd.toml
@@ -16,3 +16,4 @@
     address = ":8000"
 
 [providers.kubernetesCRD]
+  allowCrossNamespace = false
diff --git a/integration/k8s_test.go b/integration/k8s_test.go
index 60bd25b36..728e326e0 100644
--- a/integration/k8s_test.go
+++ b/integration/k8s_test.go
@@ -53,6 +53,7 @@ func (s *K8sSuite) TearDownSuite(c *check.C) {
 		"./fixtures/k8s/coredns.yaml",
 		"./fixtures/k8s/rolebindings.yaml",
 		"./fixtures/k8s/traefik.yaml",
+		"./fixtures/k8s/ccm.yaml",
 	}
 
 	for _, filename := range generatedFiles {
diff --git a/integration/testdata/rawdata-crd.json b/integration/testdata/rawdata-crd.json
index 570bee4d4..193f2ed13 100644
--- a/integration/testdata/rawdata-crd.json
+++ b/integration/testdata/rawdata-crd.json
@@ -50,6 +50,20 @@
 			"using": [
 				"web"
 			]
+		},
+		"other-ns-test6-route-482e4988e134701d8cc8@kubernetescrd": {
+			"entryPoints": [
+				"web"
+			],
+			"service": "other-ns-wrr3",
+			"rule": "Host(`foo.com`) \u0026\u0026 PathPrefix(`/c`)",
+			"error": [
+				"the service \"other-ns-wrr3@kubernetescrd\" does not exist"
+			],
+			"status": "disabled",
+			"using": [
+				"web"
+			]
 		}
 	},
 	"middlewares": {
@@ -64,6 +78,14 @@
 				"default-test2-route-23c7f4c450289ee29016@kubernetescrd"
 			]
 		},
+		"default-stripprefix2@kubernetescrd": {
+			"stripPrefix": {
+				"prefixes": [
+					"/tobestripped"
+				]
+			},
+			"status": "enabled"
+		},
 		"default-stripprefix@kubernetescrd": {
 			"stripPrefix": {
 				"prefixes": [
@@ -172,6 +194,17 @@
 				"default-test3-route-7d0ac22d3d8db4b82618@kubernetescrd"
 			]
 		},
+		"default-wrr2@kubernetescrd": {
+			"weighted": {
+				"services": [
+					{
+						"name": "default-whoami-80",
+						"weight": 1
+					}
+				]
+			},
+			"status": "enabled"
+		},
 		"noop@internal": {
 			"status": "enabled"
 		}
diff --git a/pkg/provider/kubernetes/crd/fixtures/services.yml b/pkg/provider/kubernetes/crd/fixtures/services.yml
index 50d6d65c6..7d39877c4 100644
--- a/pkg/provider/kubernetes/crd/fixtures/services.yml
+++ b/pkg/provider/kubernetes/crd/fixtures/services.yml
@@ -199,3 +199,33 @@ spec:
     - name: http
       protocol: TCP
       port: 8080
+
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: whoami-svc
+  namespace: cross-ns
+
+spec:
+  ports:
+    - name: web
+      port: 80
+  selector:
+    app: traefiklabs
+    task: whoami
+
+---
+kind: Endpoints
+apiVersion: v1
+metadata:
+  name: whoami-svc
+  namespace: cross-ns
+
+subsets:
+  - addresses:
+      - ip: 10.10.0.1
+      - ip: 10.10.0.2
+    ports:
+      - name: web
+        port: 80
diff --git a/pkg/provider/kubernetes/crd/fixtures/tcp/services.yml b/pkg/provider/kubernetes/crd/fixtures/tcp/services.yml
index 32a854c8a..1f1377343 100644
--- a/pkg/provider/kubernetes/crd/fixtures/tcp/services.yml
+++ b/pkg/provider/kubernetes/crd/fixtures/tcp/services.yml
@@ -208,3 +208,33 @@ metadata:
 spec:
   externalName: "fe80::200:5aee:feaa:20a2"
   type: ExternalName
+
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: whoamitcp-cross-ns
+  namespace: cross-ns
+
+spec:
+  ports:
+    - name: myapp
+      port: 8000
+  selector:
+    app: traefiklabs
+    task: whoamitcp
+
+---
+kind: Endpoints
+apiVersion: v1
+metadata:
+  name: whoamitcp-cross-ns
+  namespace: cross-ns
+
+subsets:
+  - addresses:
+      - ip: 10.10.0.1
+      - ip: 10.10.0.2
+    ports:
+      - name: myapp
+        port: 8000
diff --git a/pkg/provider/kubernetes/crd/fixtures/tcp/with_cross_namespace.yml b/pkg/provider/kubernetes/crd/fixtures/tcp/with_cross_namespace.yml
new file mode 100644
index 000000000..c7ba22f19
--- /dev/null
+++ b/pkg/provider/kubernetes/crd/fixtures/tcp/with_cross_namespace.yml
@@ -0,0 +1,16 @@
+apiVersion: traefik.containo.us/v1alpha1
+kind: IngressRouteTCP
+metadata:
+  name: test.route
+  namespace: default
+
+spec:
+  entryPoints:
+    - foo
+
+  routes:
+  - match: HostSNI(`foo.com`)
+    services:
+    - name: whoamitcp-cross-ns
+      namespace: cross-ns
+      port: 8000
diff --git a/pkg/provider/kubernetes/crd/fixtures/udp/services.yml b/pkg/provider/kubernetes/crd/fixtures/udp/services.yml
index f1c0abe18..887ddc385 100644
--- a/pkg/provider/kubernetes/crd/fixtures/udp/services.yml
+++ b/pkg/provider/kubernetes/crd/fixtures/udp/services.yml
@@ -130,3 +130,33 @@ subsets:
     ports:
       - name: myapp-ipv6
         port: 8080
+
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: whoamiudp-cross-ns
+  namespace: cross-ns
+
+spec:
+  ports:
+    - name: myapp
+      port: 8000
+  selector:
+    app: traefiklabs
+    task: whoamiudp
+
+---
+kind: Endpoints
+apiVersion: v1
+metadata:
+  name: whoamiudp-cross-ns
+  namespace: cross-ns
+
+subsets:
+  - addresses:
+      - ip: 10.10.0.1
+      - ip: 10.10.0.2
+    ports:
+      - name: myapp
+        port: 8000
diff --git a/pkg/provider/kubernetes/crd/fixtures/udp/with_cross_namespace.yml b/pkg/provider/kubernetes/crd/fixtures/udp/with_cross_namespace.yml
new file mode 100644
index 000000000..8df091d70
--- /dev/null
+++ b/pkg/provider/kubernetes/crd/fixtures/udp/with_cross_namespace.yml
@@ -0,0 +1,15 @@
+apiVersion: traefik.containo.us/v1alpha1
+kind: IngressRouteUDP
+metadata:
+  name: test.route
+  namespace: default
+
+spec:
+  entryPoints:
+    - foo
+
+  routes:
+  - services:
+    - name: whoamiudp-cross-ns
+      namespace: cross-ns
+      port: 8000
diff --git a/pkg/provider/kubernetes/crd/fixtures/with_cross_namespace.yml b/pkg/provider/kubernetes/crd/fixtures/with_cross_namespace.yml
new file mode 100644
index 000000000..bdc98ca1e
--- /dev/null
+++ b/pkg/provider/kubernetes/crd/fixtures/with_cross_namespace.yml
@@ -0,0 +1,91 @@
+apiVersion: traefik.containo.us/v1alpha1
+kind: IngressRoute
+metadata:
+  name: cross-ns-route
+  namespace: default
+
+spec:
+  entryPoints:
+    - foo
+
+  routes:
+  - match: Host(`foo.com`) && PathPrefix(`/bar`)
+    kind: Rule
+    priority: 12
+    services:
+    - name: whoami-svc
+      namespace: cross-ns
+      port: 80
+    - name: tr-svc-wrr1
+      kind: TraefikService
+    - name: tr-svc-wrr2
+      namespace: cross-ns
+      kind: TraefikService
+    - name: tr-svc-mirror1
+      kind: TraefikService
+    - name: tr-svc-mirror2
+      namespace: cross-ns
+      kind: TraefikService
+
+---
+apiVersion: traefik.containo.us/v1alpha1
+kind: TraefikService
+metadata:
+  name: tr-svc-wrr1
+  namespace: default
+
+spec:
+  weighted:
+    services:
+      - name: whoami-svc
+        namespace: cross-ns
+        weight: 1
+        port: 80
+
+---
+apiVersion: traefik.containo.us/v1alpha1
+kind: TraefikService
+metadata:
+  name: tr-svc-wrr2
+  namespace: cross-ns
+
+spec:
+  weighted:
+    services:
+      - name: whoami-svc
+        weight: 1
+        port: 80
+
+---
+apiVersion: traefik.containo.us/v1alpha1
+kind: TraefikService
+metadata:
+  name: tr-svc-mirror1
+  namespace: default
+
+spec:
+  mirroring:
+    name: whoami
+    port: 80
+    mirrors:
+      - name: whoami-svc
+        namespace: cross-ns
+        percent: 20
+        port: 80
+
+---
+apiVersion: traefik.containo.us/v1alpha1
+kind: TraefikService
+metadata:
+  name: tr-svc-mirror2
+  namespace: cross-ns
+
+spec:
+  mirroring:
+    name: whoami-svc
+    port: 80
+    mirrors:
+      - name: whoami-svc
+        namespace: cross-ns
+        percent: 20
+        port: 80
diff --git a/pkg/provider/kubernetes/crd/fixtures/with_middleware_cross_namespace.yml b/pkg/provider/kubernetes/crd/fixtures/with_middleware_cross_namespace.yml
new file mode 100644
index 000000000..aaed4a1d8
--- /dev/null
+++ b/pkg/provider/kubernetes/crd/fixtures/with_middleware_cross_namespace.yml
@@ -0,0 +1,58 @@
+apiVersion: traefik.containo.us/v1alpha1
+kind: IngressRoute
+metadata:
+  name: test-crossnamespace.route
+  namespace: default
+
+spec:
+  entryPoints:
+    - foo
+
+  routes:
+  - match: Host(`foo.com`) && PathPrefix(`/bar`)
+    kind: Rule
+    priority: 12
+    services:
+    - name: whoami
+      namespace: default
+      port: 80
+    middlewares:
+    - name: stripprefix
+      namespace: cross-ns
+  - match: Host(`foo.com`) && PathPrefix(`/bir`)
+    kind: Rule
+    priority: 12
+    services:
+    - name: whoami
+      namespace: default
+      port: 80
+    middlewares:
+    - name: test-errorpage
+
+---
+apiVersion: traefik.containo.us/v1alpha1
+kind: Middleware
+metadata:
+  name: stripprefix
+  namespace: cross-ns
+
+spec:
+  stripPrefix:
+    prefixes:
+      - /stripit
+
+---
+apiVersion: traefik.containo.us/v1alpha1
+kind: Middleware
+metadata:
+  name: test-errorpage
+  namespace: default
+spec:
+  errors:
+    status:
+      - 500-599
+    query: /{status}.html
+    service:
+      name: whoami-svc
+      namespace: cross-ns
+      port: 80
diff --git a/pkg/provider/kubernetes/crd/kubernetes.go b/pkg/provider/kubernetes/crd/kubernetes.go
index 3d3678a83..2a440cfc1 100644
--- a/pkg/provider/kubernetes/crd/kubernetes.go
+++ b/pkg/provider/kubernetes/crd/kubernetes.go
@@ -43,6 +43,7 @@ type Provider struct {
 	CertAuthFilePath       string          `description:"Kubernetes certificate authority file path (not needed for in-cluster client)." json:"certAuthFilePath,omitempty" toml:"certAuthFilePath,omitempty" yaml:"certAuthFilePath,omitempty"`
 	DisablePassHostHeaders bool            `description:"Kubernetes disable PassHost Headers." json:"disablePassHostHeaders,omitempty" toml:"disablePassHostHeaders,omitempty" yaml:"disablePassHostHeaders,omitempty" export:"true"`
 	Namespaces             []string        `description:"Kubernetes namespaces." json:"namespaces,omitempty" toml:"namespaces,omitempty" yaml:"namespaces,omitempty" export:"true"`
+	AllowCrossNamespace    *bool           `description:"Allow cross namespace resource reference." json:"allowCrossNamespace,omitempty" toml:"allowCrossNamespace,omitempty" yaml:"allowCrossNamespace,omitempty" export:"true"`
 	LabelSelector          string          `description:"Kubernetes label selector to use." json:"labelSelector,omitempty" toml:"labelSelector,omitempty" yaml:"labelSelector,omitempty" export:"true"`
 	IngressClass           string          `description:"Value of kubernetes.io/ingress.class annotation to watch for." json:"ingressClass,omitempty" toml:"ingressClass,omitempty" yaml:"ingressClass,omitempty" export:"true"`
 	ThrottleDuration       ptypes.Duration `description:"Ingress refresh throttle duration" json:"throttleDuration,omitempty" toml:"throttleDuration,omitempty" yaml:"throttleDuration,omitempty" export:"true"`
@@ -82,6 +83,11 @@ func (p *Provider) newK8sClient(ctx context.Context) (*clientWrapper, error) {
 	return client, nil
 }
 
+// SetDefaults sets the default values.
+func (p *Provider) SetDefaults() {
+	p.AllowCrossNamespace = func(b bool) *bool { return &b }(true)
+}
+
 // Init the provider.
 func (p *Provider) Init() error {
 	return nil
@@ -98,6 +104,10 @@ func (p *Provider) Provide(configurationChan chan<- dynamic.Message, pool *safe.
 		return err
 	}
 
+	if p.AllowCrossNamespace == nil || *p.AllowCrossNamespace {
+		logger.Warn("Cross-namespace reference between IngressRoutes and resources is enabled, please ensure that this is expected (see AllowCrossNamespace option)")
+	}
+
 	pool.GoCtx(func(ctxPool context.Context) {
 		operation := func() error {
 			eventsChan, err := k8sClient.WatchAll(p.Namespaces, ctxPool.Done())
@@ -197,7 +207,7 @@ func (p *Provider) loadConfigurationFromCRD(ctx context.Context, client Client)
 			continue
 		}
 
-		errorPage, errorPageService, err := createErrorPageMiddleware(client, middleware.Namespace, middleware.Spec.Errors)
+		errorPage, errorPageService, err := p.createErrorPageMiddleware(client, middleware.Namespace, middleware.Spec.Errors)
 		if err != nil {
 			log.FromContext(ctxMid).Errorf("Error while reading error page middleware: %v", err)
 			continue
@@ -236,7 +246,7 @@ func (p *Provider) loadConfigurationFromCRD(ctx context.Context, client Client)
 		}
 	}
 
-	cb := configBuilder{client}
+	cb := configBuilder{client, p.AllowCrossNamespace}
 	for _, service := range client.GetTraefikServices() {
 		err := cb.buildTraefikService(ctx, service, conf.HTTP.Services)
 		if err != nil {
@@ -281,7 +291,7 @@ func getServicePort(svc *corev1.Service, port int32) (*corev1.ServicePort, error
 	return &corev1.ServicePort{Port: port}, nil
 }
 
-func createErrorPageMiddleware(client Client, namespace string, errorPage *v1alpha1.ErrorPage) (*dynamic.ErrorPage, *dynamic.Service, error) {
+func (p *Provider) createErrorPageMiddleware(client Client, namespace string, errorPage *v1alpha1.ErrorPage) (*dynamic.ErrorPage, *dynamic.Service, error) {
 	if errorPage == nil {
 		return nil, nil, nil
 	}
@@ -291,7 +301,7 @@ func createErrorPageMiddleware(client Client, namespace string, errorPage *v1alp
 		Query:  errorPage.Query,
 	}
 
-	balancerServerHTTP, err := configBuilder{client}.buildServersLB(namespace, errorPage.Service.LoadBalancerSpec)
+	balancerServerHTTP, err := configBuilder{client, p.AllowCrossNamespace}.buildServersLB(namespace, errorPage.Service.LoadBalancerSpec)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -749,3 +759,8 @@ func throttleEvents(ctx context.Context, throttleDuration time.Duration, pool *s
 
 	return eventsChanBuffered
 }
+
+func isNamespaceAllowed(allowCrossNamespace *bool, parentNamespace, namespace string) bool {
+	// If allowCrossNamespace option is not defined the default behavior is to allow cross namespace references.
+	return allowCrossNamespace == nil || *allowCrossNamespace || parentNamespace == namespace
+}
diff --git a/pkg/provider/kubernetes/crd/kubernetes_http.go b/pkg/provider/kubernetes/crd/kubernetes_http.go
index 1a40c561c..b66b65b61 100644
--- a/pkg/provider/kubernetes/crd/kubernetes_http.go
+++ b/pkg/provider/kubernetes/crd/kubernetes_http.go
@@ -48,7 +48,8 @@ func (p *Provider) loadIngressRouteConfiguration(ctx context.Context, client Cli
 			ingressName = ingressRoute.GenerateName
 		}
 
-		cb := configBuilder{client}
+		cb := configBuilder{client, p.AllowCrossNamespace}
+
 		for _, route := range ingressRoute.Spec.Routes {
 			if route.Kind != "Rule" {
 				logger.Errorf("Unsupported match kind: %s. Only \"Rule\" is supported for now.", route.Kind)
@@ -66,23 +67,10 @@ func (p *Provider) loadIngressRouteConfiguration(ctx context.Context, client Cli
 				continue
 			}
 
-			var mds []string
-			for _, mi := range route.Middlewares {
-				if strings.Contains(mi.Name, providerNamespaceSeparator) {
-					if len(mi.Namespace) > 0 {
-						logger.
-							WithField(log.MiddlewareName, mi.Name).
-							Warnf("namespace %q is ignored in cross-provider context", mi.Namespace)
-					}
-					mds = append(mds, mi.Name)
-					continue
-				}
-
-				ns := mi.Namespace
-				if len(ns) == 0 {
-					ns = ingressRoute.Namespace
-				}
-				mds = append(mds, makeID(ns, mi.Name))
+			mds, err := p.makeMiddlewareKeys(ctx, ingressRoute.Namespace, route.Middlewares)
+			if err != nil {
+				logger.Errorf("Failed to create middleware keys: %v", err)
+				continue
 			}
 
 			normalized := provider.Normalize(makeID(ingressRoute.Namespace, serviceKey))
@@ -153,8 +141,38 @@ func (p *Provider) loadIngressRouteConfiguration(ctx context.Context, client Cli
 	return conf
 }
 
+func (p *Provider) makeMiddlewareKeys(ctx context.Context, ingRouteNamespace string, middlewares []v1alpha1.MiddlewareRef) ([]string, error) {
+	var mds []string
+
+	for _, mi := range middlewares {
+		if strings.Contains(mi.Name, providerNamespaceSeparator) {
+			if len(mi.Namespace) > 0 {
+				log.FromContext(ctx).
+					WithField(log.MiddlewareName, mi.Name).
+					Warnf("namespace %q is ignored in cross-provider context", mi.Namespace)
+			}
+			mds = append(mds, mi.Name)
+			continue
+		}
+
+		ns := ingRouteNamespace
+		if len(mi.Namespace) > 0 {
+			if !isNamespaceAllowed(p.AllowCrossNamespace, ingRouteNamespace, mi.Namespace) {
+				return nil, fmt.Errorf("middleware %s/%s is not in the IngressRoute namespace %s", mi.Namespace, mi.Name, ingRouteNamespace)
+			}
+
+			ns = mi.Namespace
+		}
+
+		mds = append(mds, makeID(ns, mi.Name))
+	}
+
+	return mds, nil
+}
+
 type configBuilder struct {
-	client Client
+	client              Client
+	allowCrossNamespace *bool
 }
 
 // buildTraefikService creates the configuration for the traefik service defined in tService,
@@ -270,7 +288,7 @@ func (c configBuilder) buildServersLB(namespace string, svc v1alpha1.LoadBalance
 	return &dynamic.Service{LoadBalancer: lb}, nil
 }
 
-func (c configBuilder) loadServers(fallbackNamespace string, svc v1alpha1.LoadBalancerSpec) ([]dynamic.Server, error) {
+func (c configBuilder) loadServers(parentNamespace string, svc v1alpha1.LoadBalancerSpec) ([]dynamic.Server, error) {
 	strategy := svc.Strategy
 	if strategy == "" {
 		strategy = roundRobinStrategy
@@ -279,7 +297,11 @@ func (c configBuilder) loadServers(fallbackNamespace string, svc v1alpha1.LoadBa
 		return nil, fmt.Errorf("load balancing strategy %s is not supported", strategy)
 	}
 
-	namespace := namespaceOrFallback(svc, fallbackNamespace)
+	namespace := namespaceOrFallback(svc, parentNamespace)
+
+	if !isNamespaceAllowed(c.allowCrossNamespace, parentNamespace, namespace) {
+		return nil, fmt.Errorf("load balancer service %s/%s is not in the parent resource namespace %s", svc.Namespace, svc.Name, parentNamespace)
+	}
 
 	// If the service uses explicitly the provider suffix
 	sanitizedName := strings.TrimSuffix(svc.Name, providerNamespaceSeparator+providerName)
@@ -355,10 +377,14 @@ func (c configBuilder) loadServers(fallbackNamespace string, svc v1alpha1.LoadBa
 // In addition, if the service is a Kubernetes one,
 // it generates and returns the configuration part for such a service,
 // so that the caller can add it to the global config map.
-func (c configBuilder) nameAndService(ctx context.Context, namespaceService string, service v1alpha1.LoadBalancerSpec) (string, *dynamic.Service, error) {
+func (c configBuilder) nameAndService(ctx context.Context, parentNamespace string, service v1alpha1.LoadBalancerSpec) (string, *dynamic.Service, error) {
 	svcCtx := log.With(ctx, log.Str(log.ServiceName, service.Name))
 
-	namespace := namespaceOrFallback(service, namespaceService)
+	namespace := namespaceOrFallback(service, parentNamespace)
+
+	if !isNamespaceAllowed(c.allowCrossNamespace, parentNamespace, namespace) {
+		return "", nil, fmt.Errorf("service %s/%s not in the parent resource namespace %s", service.Namespace, service.Name, parentNamespace)
+	}
 
 	switch {
 	case service.Kind == "" || service.Kind == "Service":
diff --git a/pkg/provider/kubernetes/crd/kubernetes_tcp.go b/pkg/provider/kubernetes/crd/kubernetes_tcp.go
index abf29bb8e..915ed4cd6 100644
--- a/pkg/provider/kubernetes/crd/kubernetes_tcp.go
+++ b/pkg/provider/kubernetes/crd/kubernetes_tcp.go
@@ -55,7 +55,7 @@ func (p *Provider) loadIngressRouteTCPConfiguration(ctx context.Context, client
 			serviceName := makeID(ingressRouteTCP.Namespace, key)
 
 			for _, service := range route.Services {
-				balancerServerTCP, err := createLoadBalancerServerTCP(client, ingressRouteTCP.Namespace, service)
+				balancerServerTCP, err := p.createLoadBalancerServerTCP(client, ingressRouteTCP.Namespace, service)
 				if err != nil {
 					logger.
 						WithField("serviceName", service.Name).
@@ -125,9 +125,13 @@ func (p *Provider) loadIngressRouteTCPConfiguration(ctx context.Context, client
 	return conf
 }
 
-func createLoadBalancerServerTCP(client Client, namespace string, service v1alpha1.ServiceTCP) (*dynamic.TCPService, error) {
-	ns := namespace
+func (p *Provider) createLoadBalancerServerTCP(client Client, parentNamespace string, service v1alpha1.ServiceTCP) (*dynamic.TCPService, error) {
+	ns := parentNamespace
 	if len(service.Namespace) > 0 {
+		if !isNamespaceAllowed(p.AllowCrossNamespace, parentNamespace, service.Namespace) {
+			return nil, fmt.Errorf("tcp service %s/%s is not in the parent resource namespace %s", service.Namespace, service.Name, parentNamespace)
+		}
+
 		ns = service.Namespace
 	}
 
diff --git a/pkg/provider/kubernetes/crd/kubernetes_test.go b/pkg/provider/kubernetes/crd/kubernetes_test.go
index b866f20cb..aff6eb964 100644
--- a/pkg/provider/kubernetes/crd/kubernetes_test.go
+++ b/pkg/provider/kubernetes/crd/kubernetes_test.go
@@ -2,13 +2,21 @@ package crd
 
 import (
 	"context"
+	"io/ioutil"
+	"path/filepath"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"github.com/traefik/traefik/v2/pkg/config/dynamic"
 	"github.com/traefik/traefik/v2/pkg/provider"
+	crdfake "github.com/traefik/traefik/v2/pkg/provider/kubernetes/crd/generated/clientset/versioned/fake"
+	"github.com/traefik/traefik/v2/pkg/provider/kubernetes/crd/traefik/v1alpha1"
+	"github.com/traefik/traefik/v2/pkg/provider/kubernetes/k8s"
 	"github.com/traefik/traefik/v2/pkg/tls"
 	corev1 "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	kubefake "k8s.io/client-go/kubernetes/fake"
 )
 
 var _ provider.Provider = (*Provider)(nil)
@@ -1122,7 +1130,10 @@ func TestLoadIngressRouteTCPs(t *testing.T) {
 			}
 
 			p := Provider{IngressClass: test.ingressClass}
-			conf := p.loadConfigurationFromCRD(context.Background(), newClientMock(test.paths...))
+			p.SetDefaults()
+
+			clientMock := newClientMock(test.paths...)
+			conf := p.loadConfigurationFromCRD(context.Background(), clientMock)
 			assert.Equal(t, test.expected, conf)
 		})
 	}
@@ -3187,7 +3198,10 @@ func TestLoadIngressRoutes(t *testing.T) {
 			}
 
 			p := Provider{IngressClass: test.ingressClass}
-			conf := p.loadConfigurationFromCRD(context.Background(), newClientMock(test.paths...))
+			p.SetDefaults()
+
+			clientMock := newClientMock(test.paths...)
+			conf := p.loadConfigurationFromCRD(context.Background(), clientMock)
 			assert.Equal(t, test.expected, conf)
 		})
 	}
@@ -3495,7 +3509,10 @@ func TestLoadIngressRouteUDPs(t *testing.T) {
 			}
 
 			p := Provider{IngressClass: test.ingressClass}
-			conf := p.loadConfigurationFromCRD(context.Background(), newClientMock(test.paths...))
+			p.SetDefaults()
+
+			clientMock := newClientMock(test.paths...)
+			conf := p.loadConfigurationFromCRD(context.Background(), clientMock)
 			assert.Equal(t, test.expected, conf)
 		})
 	}
@@ -3714,3 +3731,563 @@ func TestGetServicePort(t *testing.T) {
 		})
 	}
 }
+
+func TestCrossNamespace(t *testing.T) {
+	testCases := []struct {
+		desc                string
+		allowCrossNamespace bool
+		ingressClass        string
+		paths               []string
+		expected            *dynamic.Configuration
+	}{
+		{
+			desc: "Empty",
+			expected: &dynamic.Configuration{
+				UDP: &dynamic.UDPConfiguration{
+					Routers:  map[string]*dynamic.UDPRouter{},
+					Services: map[string]*dynamic.UDPService{},
+				},
+				TCP: &dynamic.TCPConfiguration{
+					Routers:  map[string]*dynamic.TCPRouter{},
+					Services: map[string]*dynamic.TCPService{},
+				},
+				HTTP: &dynamic.HTTPConfiguration{
+					Routers:     map[string]*dynamic.Router{},
+					Middlewares: map[string]*dynamic.Middleware{},
+					Services:    map[string]*dynamic.Service{},
+				},
+				TLS: &dynamic.TLSConfiguration{},
+			},
+		},
+		{
+			desc:  "HTTP middleware cross namespace disallowed",
+			paths: []string{"services.yml", "with_middleware_cross_namespace.yml"},
+			expected: &dynamic.Configuration{
+				UDP: &dynamic.UDPConfiguration{
+					Routers:  map[string]*dynamic.UDPRouter{},
+					Services: map[string]*dynamic.UDPService{},
+				},
+				TCP: &dynamic.TCPConfiguration{
+					Routers:  map[string]*dynamic.TCPRouter{},
+					Services: map[string]*dynamic.TCPService{},
+				},
+				HTTP: &dynamic.HTTPConfiguration{
+					Routers: map[string]*dynamic.Router{
+						"default-test-crossnamespace-route-9313b71dbe6a649d5049": {
+							EntryPoints: []string{"foo"},
+							Service:     "default-test-crossnamespace-route-9313b71dbe6a649d5049",
+							Rule:        "Host(`foo.com`) && PathPrefix(`/bir`)",
+							Priority:    12,
+							Middlewares: []string{"default-test-errorpage"},
+						},
+					},
+					Middlewares: map[string]*dynamic.Middleware{
+						"cross-ns-stripprefix": {
+							StripPrefix: &dynamic.StripPrefix{
+								Prefixes:   []string{"/stripit"},
+								ForceSlash: false,
+							},
+						},
+					},
+					Services: map[string]*dynamic.Service{
+						"default-test-crossnamespace-route-9313b71dbe6a649d5049": {
+							LoadBalancer: &dynamic.ServersLoadBalancer{
+								Servers: []dynamic.Server{
+									{
+										URL: "http://10.10.0.1:80",
+									},
+									{
+										URL: "http://10.10.0.2:80",
+									},
+								},
+								PassHostHeader: Bool(true),
+							},
+						},
+					},
+				},
+				TLS: &dynamic.TLSConfiguration{},
+			},
+		},
+		{
+			desc:                "HTTP middleware cross namespace allowed",
+			paths:               []string{"services.yml", "with_middleware_cross_namespace.yml"},
+			allowCrossNamespace: true,
+			expected: &dynamic.Configuration{
+				UDP: &dynamic.UDPConfiguration{
+					Routers:  map[string]*dynamic.UDPRouter{},
+					Services: map[string]*dynamic.UDPService{},
+				},
+				TCP: &dynamic.TCPConfiguration{
+					Routers:  map[string]*dynamic.TCPRouter{},
+					Services: map[string]*dynamic.TCPService{},
+				},
+				HTTP: &dynamic.HTTPConfiguration{
+					Routers: map[string]*dynamic.Router{
+						"default-test-crossnamespace-route-6b204d94623b3df4370c": {
+							EntryPoints: []string{"foo"},
+							Service:     "default-test-crossnamespace-route-6b204d94623b3df4370c",
+							Rule:        "Host(`foo.com`) && PathPrefix(`/bar`)",
+							Priority:    12,
+							Middlewares: []string{
+								"cross-ns-stripprefix",
+							},
+						},
+						"default-test-crossnamespace-route-9313b71dbe6a649d5049": {
+							EntryPoints: []string{"foo"},
+							Service:     "default-test-crossnamespace-route-9313b71dbe6a649d5049",
+							Rule:        "Host(`foo.com`) && PathPrefix(`/bir`)",
+							Priority:    12,
+							Middlewares: []string{"default-test-errorpage"},
+						},
+					},
+					Middlewares: map[string]*dynamic.Middleware{
+						"cross-ns-stripprefix": {
+							StripPrefix: &dynamic.StripPrefix{
+								Prefixes:   []string{"/stripit"},
+								ForceSlash: false,
+							},
+						},
+						"default-test-errorpage": {
+							Errors: &dynamic.ErrorPage{
+								Status:  []string{"500-599"},
+								Service: "default-test-errorpage-errorpage-service",
+								Query:   "/{status}.html",
+							},
+						},
+					},
+					Services: map[string]*dynamic.Service{
+						"default-test-crossnamespace-route-6b204d94623b3df4370c": {
+							LoadBalancer: &dynamic.ServersLoadBalancer{
+								Servers: []dynamic.Server{
+									{
+										URL: "http://10.10.0.1:80",
+									},
+									{
+										URL: "http://10.10.0.2:80",
+									},
+								},
+								PassHostHeader: Bool(true),
+							},
+						},
+						"default-test-crossnamespace-route-9313b71dbe6a649d5049": {
+							LoadBalancer: &dynamic.ServersLoadBalancer{
+								Servers: []dynamic.Server{
+									{
+										URL: "http://10.10.0.1:80",
+									},
+									{
+										URL: "http://10.10.0.2:80",
+									},
+								},
+								PassHostHeader: Bool(true),
+							},
+						},
+						"default-test-errorpage-errorpage-service": {
+							LoadBalancer: &dynamic.ServersLoadBalancer{
+								Servers: []dynamic.Server{
+									{
+										URL: "http://10.10.0.1:80",
+									},
+									{
+										URL: "http://10.10.0.2:80",
+									},
+								},
+								PassHostHeader: Bool(true),
+							},
+						},
+					},
+				},
+				TLS: &dynamic.TLSConfiguration{},
+			},
+		},
+		{
+			desc:                "HTTP cross namespace allowed",
+			paths:               []string{"services.yml", "with_cross_namespace.yml"},
+			allowCrossNamespace: true,
+			expected: &dynamic.Configuration{
+				UDP: &dynamic.UDPConfiguration{
+					Routers:  map[string]*dynamic.UDPRouter{},
+					Services: map[string]*dynamic.UDPService{},
+				},
+				TCP: &dynamic.TCPConfiguration{
+					Routers:  map[string]*dynamic.TCPRouter{},
+					Services: map[string]*dynamic.TCPService{},
+				},
+				HTTP: &dynamic.HTTPConfiguration{
+					Routers: map[string]*dynamic.Router{
+						"default-cross-ns-route-6b204d94623b3df4370c": {
+							EntryPoints: []string{"foo"},
+							Service:     "default-cross-ns-route-6b204d94623b3df4370c",
+							Rule:        "Host(`foo.com`) && PathPrefix(`/bar`)",
+							Priority:    12,
+						},
+					},
+					Middlewares: map[string]*dynamic.Middleware{},
+					Services: map[string]*dynamic.Service{
+						"default-cross-ns-route-6b204d94623b3df4370c": {
+							Weighted: &dynamic.WeightedRoundRobin{
+								Services: []dynamic.WRRService{
+									{
+										Name:   "cross-ns-whoami-svc-80",
+										Weight: func(i int) *int { return &i }(1),
+									},
+									{
+										Name:   "default-tr-svc-wrr1",
+										Weight: func(i int) *int { return &i }(1),
+									},
+									{
+										Name:   "cross-ns-tr-svc-wrr2",
+										Weight: func(i int) *int { return &i }(1),
+									},
+									{
+										Name:   "default-tr-svc-mirror1",
+										Weight: func(i int) *int { return &i }(1),
+									},
+									{
+										Name:   "cross-ns-tr-svc-mirror2",
+										Weight: func(i int) *int { return &i }(1),
+									},
+								},
+							},
+						},
+						"cross-ns-whoami-svc-80": {
+							LoadBalancer: &dynamic.ServersLoadBalancer{
+								Servers: []dynamic.Server{
+									{
+										URL: "http://10.10.0.1:80",
+									},
+									{
+										URL: "http://10.10.0.2:80",
+									},
+								},
+								PassHostHeader: Bool(true),
+							},
+						},
+						"default-tr-svc-wrr1": {
+							Weighted: &dynamic.WeightedRoundRobin{
+								Services: []dynamic.WRRService{
+									{
+										Name:   "cross-ns-whoami-svc-80",
+										Weight: func(i int) *int { return &i }(1),
+									},
+								},
+							},
+						},
+						"cross-ns-tr-svc-wrr2": {
+							Weighted: &dynamic.WeightedRoundRobin{
+								Services: []dynamic.WRRService{
+									{
+										Name:   "cross-ns-whoami-svc-80",
+										Weight: func(i int) *int { return &i }(1),
+									},
+								},
+							},
+						},
+						"default-tr-svc-mirror1": {
+							Mirroring: &dynamic.Mirroring{
+								Service: "default-whoami-80",
+								Mirrors: []dynamic.MirrorService{
+									{
+										Name:    "cross-ns-whoami-svc-80",
+										Percent: 20,
+									},
+								},
+							},
+						},
+						"cross-ns-tr-svc-mirror2": {
+							Mirroring: &dynamic.Mirroring{
+								Service: "cross-ns-whoami-svc-80",
+								Mirrors: []dynamic.MirrorService{
+									{
+										Name:    "cross-ns-whoami-svc-80",
+										Percent: 20,
+									},
+								},
+							},
+						},
+						"default-whoami-80": {
+							LoadBalancer: &dynamic.ServersLoadBalancer{
+								Servers: []dynamic.Server{
+									{
+										URL: "http://10.10.0.1:80",
+									},
+									{
+										URL: "http://10.10.0.2:80",
+									},
+								},
+								PassHostHeader: Bool(true),
+							},
+						},
+					},
+				},
+				TLS: &dynamic.TLSConfiguration{},
+			},
+		},
+		{
+			desc:  "HTTP cross namespace disallowed",
+			paths: []string{"services.yml", "with_cross_namespace.yml"},
+			expected: &dynamic.Configuration{
+				UDP: &dynamic.UDPConfiguration{
+					Routers:  map[string]*dynamic.UDPRouter{},
+					Services: map[string]*dynamic.UDPService{},
+				},
+				TCP: &dynamic.TCPConfiguration{
+					Routers:  map[string]*dynamic.TCPRouter{},
+					Services: map[string]*dynamic.TCPService{},
+				},
+				HTTP: &dynamic.HTTPConfiguration{
+					Routers:     map[string]*dynamic.Router{},
+					Middlewares: map[string]*dynamic.Middleware{},
+					Services: map[string]*dynamic.Service{
+						"cross-ns-tr-svc-wrr2": {
+							Weighted: &dynamic.WeightedRoundRobin{
+								Services: []dynamic.WRRService{
+									{
+										Name:   "cross-ns-whoami-svc-80",
+										Weight: func(i int) *int { return &i }(1),
+									},
+								},
+							},
+						},
+						"cross-ns-whoami-svc-80": {
+							LoadBalancer: &dynamic.ServersLoadBalancer{
+								Servers: []dynamic.Server{
+									{
+										URL: "http://10.10.0.1:80",
+									},
+									{
+										URL: "http://10.10.0.2:80",
+									},
+								},
+								PassHostHeader: Bool(true),
+							},
+						},
+						"cross-ns-tr-svc-mirror2": {
+							Mirroring: &dynamic.Mirroring{
+								Service: "cross-ns-whoami-svc-80",
+								Mirrors: []dynamic.MirrorService{
+									{
+										Name:    "cross-ns-whoami-svc-80",
+										Percent: 20,
+									},
+								},
+							},
+						},
+						"default-whoami-80": {
+							LoadBalancer: &dynamic.ServersLoadBalancer{
+								Servers: []dynamic.Server{
+									{
+										URL: "http://10.10.0.1:80",
+									},
+									{
+										URL: "http://10.10.0.2:80",
+									},
+								},
+								PassHostHeader: Bool(true),
+							},
+						},
+					},
+				},
+				TLS: &dynamic.TLSConfiguration{},
+			},
+		},
+		{
+			desc:                "TCP cross namespace allowed",
+			paths:               []string{"tcp/services.yml", "tcp/with_cross_namespace.yml"},
+			allowCrossNamespace: true,
+			expected: &dynamic.Configuration{
+				UDP: &dynamic.UDPConfiguration{
+					Routers:  map[string]*dynamic.UDPRouter{},
+					Services: map[string]*dynamic.UDPService{},
+				},
+				HTTP: &dynamic.HTTPConfiguration{
+					Routers:     map[string]*dynamic.Router{},
+					Middlewares: map[string]*dynamic.Middleware{},
+					Services:    map[string]*dynamic.Service{},
+				},
+				TCP: &dynamic.TCPConfiguration{
+					Routers: map[string]*dynamic.TCPRouter{
+						"default-test.route-fdd3e9338e47a45efefc": {
+							EntryPoints: []string{"foo"},
+							Service:     "default-test.route-fdd3e9338e47a45efefc",
+							Rule:        "HostSNI(`foo.com`)",
+						},
+					},
+					Services: map[string]*dynamic.TCPService{
+						"default-test.route-fdd3e9338e47a45efefc": {
+							LoadBalancer: &dynamic.TCPServersLoadBalancer{
+								Servers: []dynamic.TCPServer{
+									{
+										Address: "10.10.0.1:8000",
+										Port:    "",
+									},
+									{
+										Address: "10.10.0.2:8000",
+										Port:    "",
+									},
+								},
+							},
+						},
+					},
+				},
+				TLS: &dynamic.TLSConfiguration{},
+			},
+		},
+		{
+			desc:  "TCP cross namespace disallowed",
+			paths: []string{"tcp/services.yml", "tcp/with_cross_namespace.yml"},
+			expected: &dynamic.Configuration{
+				UDP: &dynamic.UDPConfiguration{
+					Routers:  map[string]*dynamic.UDPRouter{},
+					Services: map[string]*dynamic.UDPService{},
+				},
+				TCP: &dynamic.TCPConfiguration{
+					// The router that references the invalid service will be discarded.
+					Routers: map[string]*dynamic.TCPRouter{
+						"default-test.route-fdd3e9338e47a45efefc": {
+							EntryPoints: []string{"foo"},
+							Service:     "default-test.route-fdd3e9338e47a45efefc",
+							Rule:        "HostSNI(`foo.com`)",
+						},
+					},
+					Services: map[string]*dynamic.TCPService{},
+				},
+				HTTP: &dynamic.HTTPConfiguration{
+					Routers:     map[string]*dynamic.Router{},
+					Middlewares: map[string]*dynamic.Middleware{},
+					Services:    map[string]*dynamic.Service{},
+				},
+				TLS: &dynamic.TLSConfiguration{},
+			},
+		},
+		{
+			desc:                "UDP cross namespace allowed",
+			paths:               []string{"udp/services.yml", "udp/with_cross_namespace.yml"},
+			allowCrossNamespace: true,
+			expected: &dynamic.Configuration{
+				UDP: &dynamic.UDPConfiguration{
+					Routers: map[string]*dynamic.UDPRouter{
+						"default-test.route-0": {
+							EntryPoints: []string{"foo"},
+							Service:     "default-test.route-0",
+						},
+					},
+					Services: map[string]*dynamic.UDPService{
+						"default-test.route-0": {
+							LoadBalancer: &dynamic.UDPServersLoadBalancer{
+								Servers: []dynamic.UDPServer{
+									{
+										Address: "10.10.0.1:8000",
+										Port:    "",
+									},
+									{
+										Address: "10.10.0.2:8000",
+										Port:    "",
+									},
+								},
+							},
+						},
+					},
+				},
+				HTTP: &dynamic.HTTPConfiguration{
+					Routers:     map[string]*dynamic.Router{},
+					Middlewares: map[string]*dynamic.Middleware{},
+					Services:    map[string]*dynamic.Service{},
+				},
+				TCP: &dynamic.TCPConfiguration{
+					Routers:  map[string]*dynamic.TCPRouter{},
+					Services: map[string]*dynamic.TCPService{},
+				},
+				TLS: &dynamic.TLSConfiguration{},
+			},
+		},
+		{
+			desc:  "UDP cross namespace disallowed",
+			paths: []string{"udp/services.yml", "udp/with_cross_namespace.yml"},
+			expected: &dynamic.Configuration{
+				// The router that references the invalid service will be discarded.
+				UDP: &dynamic.UDPConfiguration{
+					Routers: map[string]*dynamic.UDPRouter{
+						"default-test.route-0": {
+							EntryPoints: []string{"foo"},
+							Service:     "default-test.route-0",
+						},
+					},
+					Services: map[string]*dynamic.UDPService{},
+				},
+				TCP: &dynamic.TCPConfiguration{
+					Routers:  map[string]*dynamic.TCPRouter{},
+					Services: map[string]*dynamic.TCPService{},
+				},
+				HTTP: &dynamic.HTTPConfiguration{
+					Routers:     map[string]*dynamic.Router{},
+					Middlewares: map[string]*dynamic.Middleware{},
+					Services:    map[string]*dynamic.Service{},
+				},
+				TLS: &dynamic.TLSConfiguration{},
+			},
+		},
+	}
+
+	for _, test := range testCases {
+		test := test
+
+		t.Run(test.desc, func(t *testing.T) {
+			t.Parallel()
+
+			var k8sObjects []runtime.Object
+			var crdObjects []runtime.Object
+			for _, path := range test.paths {
+				yamlContent, err := ioutil.ReadFile(filepath.FromSlash("./fixtures/" + path))
+				if err != nil {
+					panic(err)
+				}
+
+				objects := k8s.MustParseYaml(yamlContent)
+				for _, obj := range objects {
+					switch o := obj.(type) {
+					case *corev1.Service, *corev1.Endpoints, *corev1.Secret:
+						k8sObjects = append(k8sObjects, o)
+					case *v1alpha1.IngressRoute:
+						crdObjects = append(crdObjects, o)
+					case *v1alpha1.IngressRouteTCP:
+						crdObjects = append(crdObjects, o)
+					case *v1alpha1.IngressRouteUDP:
+						crdObjects = append(crdObjects, o)
+					case *v1alpha1.Middleware:
+						crdObjects = append(crdObjects, o)
+					case *v1alpha1.TraefikService:
+						crdObjects = append(crdObjects, o)
+					case *v1alpha1.TLSOption:
+						crdObjects = append(crdObjects, o)
+					case *v1alpha1.TLSStore:
+						crdObjects = append(crdObjects, o)
+					default:
+					}
+				}
+			}
+
+			kubeClient := kubefake.NewSimpleClientset(k8sObjects...)
+			crdClient := crdfake.NewSimpleClientset(crdObjects...)
+
+			client := newClientImpl(kubeClient, crdClient)
+
+			stopCh := make(chan struct{})
+
+			eventCh, err := client.WatchAll([]string{"default", "cross-ns"}, stopCh)
+			require.NoError(t, err)
+
+			if k8sObjects != nil || crdObjects != nil {
+				// just wait for the first event
+				<-eventCh
+			}
+
+			p := Provider{}
+			p.SetDefaults()
+
+			p.AllowCrossNamespace = func(b bool) *bool { return &b }(test.allowCrossNamespace)
+			conf := p.loadConfigurationFromCRD(context.Background(), client)
+			assert.Equal(t, test.expected, conf)
+		})
+	}
+}
diff --git a/pkg/provider/kubernetes/crd/kubernetes_udp.go b/pkg/provider/kubernetes/crd/kubernetes_udp.go
index 2d02c8b5f..0346084a2 100644
--- a/pkg/provider/kubernetes/crd/kubernetes_udp.go
+++ b/pkg/provider/kubernetes/crd/kubernetes_udp.go
@@ -36,7 +36,7 @@ func (p *Provider) loadIngressRouteUDPConfiguration(ctx context.Context, client
 			serviceName := makeID(ingressRouteUDP.Namespace, key)
 
 			for _, service := range route.Services {
-				balancerServerUDP, err := createLoadBalancerServerUDP(client, ingressRouteUDP.Namespace, service)
+				balancerServerUDP, err := p.createLoadBalancerServerUDP(client, ingressRouteUDP.Namespace, service)
 				if err != nil {
 					logger.
 						WithField("serviceName", service.Name).
@@ -77,9 +77,13 @@ func (p *Provider) loadIngressRouteUDPConfiguration(ctx context.Context, client
 	return conf
 }
 
-func createLoadBalancerServerUDP(client Client, namespace string, service v1alpha1.ServiceUDP) (*dynamic.UDPService, error) {
-	ns := namespace
+func (p *Provider) createLoadBalancerServerUDP(client Client, parentNamespace string, service v1alpha1.ServiceUDP) (*dynamic.UDPService, error) {
+	ns := parentNamespace
 	if len(service.Namespace) > 0 {
+		if !isNamespaceAllowed(p.AllowCrossNamespace, parentNamespace, service.Namespace) {
+			return nil, fmt.Errorf("udp service %s/%s is not in the parent resource namespace %s", service.Namespace, service.Name, ns)
+		}
+
 		ns = service.Namespace
 	}
 

From 42d8e6d60def0b49e2de4720b3ad16dc5901f3c3 Mon Sep 17 00:00:00 2001
From: Romain <rtribotte@users.noreply.github.com>
Date: Thu, 10 Dec 2020 16:48:04 +0100
Subject: [PATCH 14/14] Prepare release v2.3.5

---
 CHANGELOG.md                   | 15 +++++++++++++++
 script/gcg/traefik-bugfix.toml |  6 +++---
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0f718aead..e7b266e52 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,18 @@
+## [v2.3.5](https://github.com/traefik/traefik/tree/v2.3.5) (2020-12-10)
+[All Commits](https://github.com/traefik/traefik/compare/v2.3.4...v2.3.5)
+
+**Bug fixes:**
+- **[acme]** Update go-acme/lego to v4.1.3 ([#7625](https://github.com/traefik/traefik/pull/7625) by [ldez](https://github.com/ldez))
+- **[k8s,k8s/crd]** IngressRoute: add an option to disable cross-namespace routing ([#7595](https://github.com/traefik/traefik/pull/7595) by [rtribotte](https://github.com/rtribotte))
+- **[k8s/crd,k8s/ingress]** Fix concatenation of IPv6 addresses and ports ([#7620](https://github.com/traefik/traefik/pull/7620) by [jspdown](https://github.com/jspdown))
+- **[tcp,tls]** Fix TLS options fallback when domain and options are the same  ([#7609](https://github.com/traefik/traefik/pull/7609) by [jspdown](https://github.com/jspdown))
+- **[webui]** Fix UI bug on long service name ([#7535](https://github.com/traefik/traefik/pull/7535) by [ipinak](https://github.com/ipinak))
+
+**Documentation:**
+- **[docker]** Add example for multiple service per container ([#7610](https://github.com/traefik/traefik/pull/7610) by [notsureifkevin](https://github.com/notsureifkevin))
+- Documentation: Add spacing to sidebars so the last item is always visible ([#7616](https://github.com/traefik/traefik/pull/7616) by [paulocfjunior](https://github.com/paulocfjunior))
+- Fix typos in migration guide  ([#7596](https://github.com/traefik/traefik/pull/7596) by [marsavela](https://github.com/marsavela))
+
 ## [v2.3.4](https://github.com/traefik/traefik/tree/v2.3.4) (2020-11-24)
 [All Commits](https://github.com/traefik/traefik/compare/v2.3.3...v2.3.4)
 
diff --git a/script/gcg/traefik-bugfix.toml b/script/gcg/traefik-bugfix.toml
index 3b6392736..408b454d1 100644
--- a/script/gcg/traefik-bugfix.toml
+++ b/script/gcg/traefik-bugfix.toml
@@ -4,11 +4,11 @@ RepositoryName = "traefik"
 OutputType = "file"
 FileName = "traefik_changelog.md"
 
-# example new bugfix v2.3.4
+# example new bugfix v2.3.5
 CurrentRef = "v2.3"
-PreviousRef = "v2.3.3"
+PreviousRef = "v2.3.4"
 BaseBranch = "v2.3"
-FutureCurrentRefName = "v2.3.4"
+FutureCurrentRefName = "v2.3.5"
 
 ThresholdPreviousRef = 10
 ThresholdCurrentRef = 10