Fix for possible crashes due to pointer value being null

content/renderer/render_frame_impl.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/render_frame_impl.h"
 
 #include <map>
 #include <string>
 
 #include "base/auto_reset.h"
@@ skipping 3754 matching lines @@
       params.referrer =
           Referrer(params.redirects[0], ds->request().referrerPolicy());
       params.transition = ui::PageTransitionFromInt(
           params.transition | ui::PAGE_TRANSITION_CLIENT_REDIRECT);
     } else {
       params.referrer = RenderViewImpl::GetReferrerFromRequest(
           frame, ds->request());
     }
 
     base::string16 method = request.httpMethod();
-    if (EqualsASCII(method, "POST")) {
+    if (entry && EqualsASCII(method, "POST")) {
       params.is_post = true;

[Charlie Reis, 2015/02/17 21:26:59]

Good catch.  I don't think we should skip this line based on the entry being
null, though.  It's still important to mark params.is_post = true.

Looking at ExtractPostId, we should probably set params.post_id to -1 if there's
no entry.  In fact, we should probably change ExtractPostId to take in the entry
and let it handle the null case, since that's what it used to do with
WebHistoryItem before @japhet's change in
https://codereview.chromium.org/248013003.

[Sunil Ratnu, 2015/02/18 09:04:45]

Done.

       params.post_id = ExtractPostId(entry->root());
     }
 
     // Send the user agent override back.
     params.is_overriding_user_agent = internal_data->is_overriding_user_agent();
 
     // Track the URL of the original request.  We use the first entry of the
     // redirect chain if it exists because the chain may have started in another
     // process.
     params.original_request_url = GetOriginalRequestURL(ds);
@@ skipping 652 matching lines @@
 
 #if defined(ENABLE_BROWSER_CDMS)
 RendererCdmManager* RenderFrameImpl::GetCdmManager() {
   if (!cdm_manager_)
     cdm_manager_ = new RendererCdmManager(this);
   return cdm_manager_;
 }
 #endif  // defined(ENABLE_BROWSER_CDMS)
 
 }  // namespace content