Receiving Connection: Proxy-Bypass induces proxy fallback.

net/proxy/proxy_service.cc

Index: net/proxy/proxy_service.cc
diff --git a/net/proxy/proxy_service.cc b/net/proxy/proxy_service.cc
index 9989b8221cdc09944ce3e14622d3d088851b6f7e..99a3c40a9ba106733729c36d8ef73c3a5a646fbc 100644
--- a/net/proxy/proxy_service.cc
+++ b/net/proxy/proxy_service.cc
@@ -1174,6 +1174,16 @@ int ProxyService::ReconsiderProxyAfterError(const GURL& url,
   return did_fallback ? OK : ERR_FAILED;
 }
 
+bool ProxyService::MarkProxyAsBad(const ProxyInfo& result,
+                                  const BoundNetLog& net_log) {
+  result.proxy_list_.UpdateRetryInfoOnFallback(&proxy_retry_info_, net_log);
+  // Since we haven't modified proxy_list_, require at least two entries
+  // to return true. With 1 or 0, we won't have any remaining proxy entries
+  // to try after incorporating our bad proxy list, which now includes
+  // the first entry of result.proxy_list_.
+  return result.proxy_list_.size() > 1;

[eroman, 2012/10/08 22:29:25]

I don't believe this is good enough to prevent loops.

Note that the "ProxyRetryInfoMap" is not used to remove proxies from being tried
-- it is only used to "deprioritize" them. In other words, the proxy list will
be re-ordered, and so-called "bad proxies" may still be tried during fallback.

So for instance, if the proxy list was:

"foobar:80; foobar80: foobar80:", then I expect MarkProxyAsBad() would return
true every time, and we would be stuck in a resend loop if the proxy returns
proxy-bypass.

[Michael Piatek, 2012/10/09 21:05:08]

Done.

+}
+
 void ProxyService::ReportSuccess(const ProxyInfo& result) {
   DCHECK(CalledOnValidThread());