Limit QUIC uncompressed header size per stream to 16K, by default. Protected by FLAGS_quic_limit_un…

net/quic/core/quic_header_list.cc

Index: net/quic/core/quic_header_list.cc
diff --git a/net/quic/core/quic_header_list.cc b/net/quic/core/quic_header_list.cc
index df8ecac45213d9a1e54f3405dbf998591a1a257b..871c49a3ce5a54d7d2d2b769178b995351674e04 100644
--- a/net/quic/core/quic_header_list.cc
+++ b/net/quic/core/quic_header_list.cc
@@ -6,9 +6,14 @@
 
 using std::string;
 
+#include "net/quic/core/quic_flags.h"
+#include "net/quic/core/quic_protocol.h"
+
 namespace net {
 
-QuicHeaderList::QuicHeaderList() : uncompressed_header_bytes_(0) {}
+QuicHeaderList::QuicHeaderList()
+    : max_uncompressed_header_bytes_(kDefaultMaxUncompressedHeaderSize),
+      uncompressed_header_bytes_(0) {}
 
 QuicHeaderList::QuicHeaderList(QuicHeaderList&& other) = default;
 
@@ -27,18 +32,26 @@ void QuicHeaderList::OnHeaderBlockStart() {
 }
 
 void QuicHeaderList::OnHeader(base::StringPiece name, base::StringPiece value) {
-  header_list_.emplace_back(name.as_string(), value.as_string());
+  // Avoid infinte buffering of headers. No longer store headers
+  // once the current headers are over the limit.
+  if (!FLAGS_quic_limit_uncompressed_headers ||
+      uncompressed_header_bytes_ == 0 || !header_list_.empty()) {
+    header_list_.emplace_back(name.as_string(), value.as_string());
+  }
 }
 
 void QuicHeaderList::OnHeaderBlockEnd(size_t uncompressed_header_bytes) {
-  uncompressed_header_bytes_ = uncompressed_header_bytes;
-  compressed_header_bytes_ = uncompressed_header_bytes;
+  OnHeaderBlockEnd(uncompressed_header_bytes, uncompressed_header_bytes);
 }
 
 void QuicHeaderList::OnHeaderBlockEnd(size_t uncompressed_header_bytes,
                                       size_t compressed_header_bytes) {
   uncompressed_header_bytes_ = uncompressed_header_bytes;
   compressed_header_bytes_ = compressed_header_bytes;
+  if (FLAGS_quic_limit_uncompressed_headers &&
+      uncompressed_header_bytes_ > max_uncompressed_header_bytes_) {
+    Clear();
+  }
 }
 
 void QuicHeaderList::Clear() {