golang: CVE-2022-2880 ReverseProxy should not forward unparseable query parameters

Upstream-Status: Backport from https://github.com/golang/go/commit/9d2c73a9fd69e45876509bb3bdb2af99bf77da1e

Signed-off-by: Hitendra Prajapati <hprajapati@mvista.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>

2 files changed, 165 insertions, 0 deletions

diff --git a/meta/recipes-devtools/go/go-1.14.inc b/meta/recipes-devtools/go/go-1.14.inc
index 2e1d8240f6..3341beb159 100644
--- a/meta/recipes-devtools/go/go-1.14.inc
+++ b/meta/recipes-devtools/go/go-1.14.inc
@@ -41,6 +41,7 @@ SRC_URI += "\
     file://0002-CVE-2022-32190.patch \
     file://0003-CVE-2022-32190.patch \
     file://0004-CVE-2022-32190.patch \
+    file://CVE-2022-2880.patch \
 "
 
 SRC_URI_append_libc-musl = " file://0009-ld-replace-glibc-dynamic-linker-with-musl.patch"
diff --git a/meta/recipes-devtools/go/go-1.14/CVE-2022-2880.patch b/meta/recipes-devtools/go/go-1.14/CVE-2022-2880.patch
new file mode 100644
index 0000000000..8376dc45ba
--- /dev/null
+++ b/meta/recipes-devtools/go/go-1.14/CVE-2022-2880.patch
@@ -0,0 +1,164 @@
+From 753e3f8da191c2ac400407d83c70f46900769417 Mon Sep 17 00:00:00 2001
+From: Hitendra Prajapati <hprajapati@mvista.com>
+Date: Thu, 27 Oct 2022 12:22:41 +0530
+Subject: [PATCH] CVE-2022-2880
+
+Upstream-Status: Backport [https://github.com/golang/go/commit/9d2c73a9fd69e45876509bb3bdb2af99bf77da1e]
+CVE: CVE-2022-2880
+Signed-off-by: Hitendra Prajapati <hprajapati@mvista.com>
+
+net/http/httputil: avoid query parameter
+
+Query parameter smuggling occurs when a proxy's interpretation
+of query parameters differs from that of a downstream server.
+Change ReverseProxy to avoid forwarding ignored query parameters.
+
+Remove unparsable query parameters from the outbound request
+
+   * if req.Form != nil after calling ReverseProxy.Director; and
+   * before calling ReverseProxy.Rewrite.
+
+This change preserves the existing behavior of forwarding the
+raw query untouched if a Director hook does not parse the query
+by calling Request.ParseForm (possibly indirectly).
+---
+ src/net/http/httputil/reverseproxy.go      | 36 +++++++++++
+ src/net/http/httputil/reverseproxy_test.go | 74 ++++++++++++++++++++++
+ 2 files changed, 110 insertions(+)
+
+diff --git a/src/net/http/httputil/reverseproxy.go b/src/net/http/httputil/reverseproxy.go
+index 2072a5f..c6fb873 100644
+--- a/src/net/http/httputil/reverseproxy.go
++++ b/src/net/http/httputil/reverseproxy.go
+@@ -212,6 +212,9 @@ func (p *ReverseProxy) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
+ 	}
+ 
+ 	p.Director(outreq)
++	if outreq.Form != nil {
++		outreq.URL.RawQuery = cleanQueryParams(outreq.URL.RawQuery)
++	}
+ 	outreq.Close = false
+ 
+ 	reqUpType := upgradeType(outreq.Header)
+@@ -561,3 +564,36 @@ func (c switchProtocolCopier) copyToBackend(errc chan<- error) {
+ 	_, err := io.Copy(c.backend, c.user)
+ 	errc <- err
+ }
++
++func cleanQueryParams(s string) string {
++	reencode := func(s string) string {
++		v, _ := url.ParseQuery(s)
++		return v.Encode()
++	}
++	for i := 0; i < len(s); {
++		switch s[i] {
++		case ';':
++			return reencode(s)
++		case '%':
++			if i+2 >= len(s) || !ishex(s[i+1]) || !ishex(s[i+2]) {
++				return reencode(s)
++			}
++			i += 3
++		default:
++			i++
++		}
++	}
++	return s
++}
++
++func ishex(c byte) bool {
++	switch {
++	case '0' <= c && c <= '9':
++		return true
++	case 'a' <= c && c <= 'f':
++		return true
++	case 'A' <= c && c <= 'F':
++		return true
++	}
++	return false
++}
+diff --git a/src/net/http/httputil/reverseproxy_test.go b/src/net/http/httputil/reverseproxy_test.go
+index 9a7223a..bc87a3b 100644
+--- a/src/net/http/httputil/reverseproxy_test.go
++++ b/src/net/http/httputil/reverseproxy_test.go
+@@ -1269,3 +1269,77 @@ func TestSingleJoinSlash(t *testing.T) {
+ 		}
+ 	}
+ }
++
++const (
++	testWantsCleanQuery = true
++	testWantsRawQuery   = false
++)
++
++func TestReverseProxyQueryParameterSmugglingDirectorDoesNotParseForm(t *testing.T) {
++	testReverseProxyQueryParameterSmuggling(t, testWantsRawQuery, func(u *url.URL) *ReverseProxy {
++		proxyHandler := NewSingleHostReverseProxy(u)
++		oldDirector := proxyHandler.Director
++		proxyHandler.Director = func(r *http.Request) {
++			oldDirector(r)
++		}
++		return proxyHandler
++	})
++}
++
++func TestReverseProxyQueryParameterSmugglingDirectorParsesForm(t *testing.T) {
++	testReverseProxyQueryParameterSmuggling(t, testWantsCleanQuery, func(u *url.URL) *ReverseProxy {
++		proxyHandler := NewSingleHostReverseProxy(u)
++		oldDirector := proxyHandler.Director
++		proxyHandler.Director = func(r *http.Request) {
++			// Parsing the form causes ReverseProxy to remove unparsable
++			// query parameters before forwarding.
++			r.FormValue("a")
++			oldDirector(r)
++		}
++		return proxyHandler
++	})
++}
++
++func testReverseProxyQueryParameterSmuggling(t *testing.T, wantCleanQuery bool, newProxy func(*url.URL) *ReverseProxy) {
++	const content = "response_content"
++	backend := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
++		w.Write([]byte(r.URL.RawQuery))
++	}))
++	defer backend.Close()
++	backendURL, err := url.Parse(backend.URL)
++	if err != nil {
++		t.Fatal(err)
++	}
++	proxyHandler := newProxy(backendURL)
++	frontend := httptest.NewServer(proxyHandler)
++	defer frontend.Close()
++
++	// Don't spam output with logs of queries containing semicolons.
++	backend.Config.ErrorLog = log.New(io.Discard, "", 0)
++	frontend.Config.ErrorLog = log.New(io.Discard, "", 0)
++
++	for _, test := range []struct {
++		rawQuery   string
++		cleanQuery string
++	}{{
++		rawQuery:   "a=1&a=2;b=3",
++		cleanQuery: "a=1",
++	}, {
++		rawQuery:   "a=1&a=%zz&b=3",
++		cleanQuery: "a=1&b=3",
++	}} {
++		res, err := frontend.Client().Get(frontend.URL + "?" + test.rawQuery)
++		if err != nil {
++			t.Fatalf("Get: %v", err)
++		}
++		defer res.Body.Close()
++		body, _ := io.ReadAll(res.Body)
++		wantQuery := test.rawQuery
++		if wantCleanQuery {
++			wantQuery = test.cleanQuery
++		}
++		if got, want := string(body), wantQuery; got != want {
++			t.Errorf("proxy forwarded raw query %q as %q, want %q", test.rawQuery, got, want)
++		}
++	}
++}
+-- 
+2.25.1
+