Merged: [wasm] Require global names to be validate UTF-8.

Revision: 6cf621e

BUG=chromium:628542
LOG=N
NOTRY=true
NOPRESUBMIT=true
NOTREECHECKS=true
R=hablich@chromium.org

Review-Url: https://codereview.chromium.org/2248213003
Cr-Commit-Position: refs/branch-heads/5.3@{#44}
Cr-Branched-From: 820a23a-refs/heads/5.3.332@{#2}
Cr-Branched-From: 37538cb-refs/heads/master@{#37308}

src/wasm/module-decoder.cc

@@ -479,8 +479,10 @@ class ModuleDecoder : public Decoder {
   // Decodes a single global entry inside a module starting at {pc_}.
   void DecodeGlobalInModule(WasmGlobal* global) {
     global->name_offset = consume_string(&global->name_length, false);
-    DCHECK(unibrow::Utf8::Validate(start_ + global->name_offset,
-                                   global->name_length));
+    if(!unibrow::Utf8::Validate(start_ + global->name_offset,
+                                global->name_length)) {
+      error("global name is not valid utf8");
+    }
     global->type = mem_type();
     global->offset = 0;
     global->exported = consume_u8("exported") != 0;