RenderFrameProxyHost::OnOpenURL needs to validate resource request body.

content/browser/frame_host/render_frame_proxy_host.cc

Index: content/browser/frame_host/render_frame_proxy_host.cc
diff --git a/content/browser/frame_host/render_frame_proxy_host.cc b/content/browser/frame_host/render_frame_proxy_host.cc
index 1107e77fe4508b99b5a2f3446bf766bf59c7ad7d..725492de62a2806e96b3234b355c3a9c45fc98cc 100644
--- a/content/browser/frame_host/render_frame_proxy_host.cc
+++ b/content/browser/frame_host/render_frame_proxy_host.cc
@@ -8,6 +8,7 @@
 
 #include "base/lazy_instance.h"
 #include "content/browser/bad_message.h"
+#include "content/browser/child_process_security_policy_impl.h"
 #include "content/browser/frame_host/cross_process_frame_connector.h"
 #include "content/browser/frame_host/frame_tree.h"
 #include "content/browser/frame_host/frame_tree_node.h"
@@ -32,7 +33,8 @@ typedef base::hash_map<RenderFrameProxyHostID, RenderFrameProxyHost*>
     RoutingIDFrameProxyMap;
 base::LazyInstance<RoutingIDFrameProxyMap>::DestructorAtExit
     g_routing_id_frame_proxy_map = LAZY_INSTANCE_INITIALIZER;
-}
+
+}  // namespace
 
 // static
 RenderFrameProxyHost* RenderFrameProxyHost::FromID(int process_id,
@@ -250,6 +252,15 @@ void RenderFrameProxyHost::OnOpenURL(
   if (!site_instance_->IsRelatedSiteInstance(current_rfh->GetSiteInstance()))
     return;
 
+  // Verify if the request originator (*not* |current_rfh|) has access to the
+  // contents of the POST body.
+  if (!ChildProcessSecurityPolicyImpl::GetInstance()->CanReadRequestBody(
+          GetSiteInstance(), params.resource_request_body)) {
+    bad_message::ReceivedBadMessage(GetProcess(),
+                                    bad_message::RFPH_ILLEGAL_UPLOAD_PARAMS);
+    return;
+  }
+
   // Since this navigation targeted a specific RenderFrameProxy, it should stay
   // in the current tab.
   DCHECK_EQ(WindowOpenDisposition::CURRENT_TAB, params.disposition);