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>

diff --git a/meta/recipes-devtools/go/go-1.14.inc b/meta/recipes-devtools/go/go-1.14.inc
index 2e1d8240f6e2236d639caa897dc547c777f87d7b..3341beb159f42952f3ed4096e0deb24d6d8e252d 100644 (file)
--- 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 (file)
index 0000000..8376dc4
--- /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
+