Safebrowsing: Fix failure parsing a gethash result with bad listname and metadata.

chrome/browser/safe_browsing/protocol_parser.cc

Index: chrome/browser/safe_browsing/protocol_parser.cc
diff --git a/chrome/browser/safe_browsing/protocol_parser.cc b/chrome/browser/safe_browsing/protocol_parser.cc
index 82cbce79d935fc9f6ebf720dddd52df9f2fc9d92..9c5ea88e66b58e2ed78d0d1474d641bb3f74f34b 100644
--- a/chrome/browser/safe_browsing/protocol_parser.cc
+++ b/chrome/browser/safe_browsing/protocol_parser.cc
@@ -131,6 +131,23 @@ class BufferReader {
   DISALLOW_COPY_AND_ASSIGN(BufferReader);
 };
 
+bool ParseGetHashMetadata(size_t hash_count, BufferReader* reader) {
+  for (size_t i = 0; i < hash_count; ++i) {
+    base::StringPiece line;
+    if (!reader->GetLine(&line))
+      return false;
+
+    size_t meta_data_len;
+    if (!base::StringToSizeT(line, &meta_data_len))
+      return false;
+
+    const void* meta_data;
+    if (!reader->RefData(&meta_data, meta_data_len))
+      return false;
+  }
+  return true;
+}
+
 }  // namespace
 
 namespace safe_browsing {
@@ -206,6 +223,8 @@ bool ParseGetHash(const char* chunk_data,
     // Ignore hash results from lists we don't recognize.
     if (full_hash.list_id < 0) {
       reader.Advance(hash_len * hash_count);
+      if (has_metadata && !ParseGetHashMetadata(hash_count, &reader))

[noé, 2014/09/18 20:41:07]

nit: can you add a TODO here to send the metadata back to the client that
triggered the gethash?  This information should be used to know which malware
interstitial to show (distribution vs. landing).

[mattm, 2014/09/18 20:50:32]

Done. 

I need to pull that out of my old api 2.3 WIP cl and update it...

+        return false;
       continue;
     }
 
@@ -216,21 +235,8 @@ bool ParseGetHash(const char* chunk_data,
     }
 
     // Discard the metadata for now.
-    if (has_metadata) {
-      for (size_t i = 0; i < hash_count; ++i) {
-        base::StringPiece line;
-        if (!reader.GetLine(&line))
-          return false;
-
-        size_t meta_data_len;
-        if (!base::StringToSizeT(line, &meta_data_len))
-          return false;
-
-        const void* meta_data;
-        if (!reader.RefData(&meta_data, meta_data_len))
-          return false;
-      }
-    }
+    if (has_metadata && !ParseGetHashMetadata(hash_count, &reader))
+      return false;
   }
 
   return reader.empty();