Fix some fragile code that is likely to cause future memory corruption

problems.

- The ordering of keys in stl containers cannot change. Make the relevant
members const to guarantee this assumption.
- Add handling and logging for demangle errors.
- Fix a potential double-delete bug if a function passed to AddFunction() is
already present.

BUG=chromium:449214
R=mark@chromium.org

Review URL: https://breakpad.appspot.com/10704002/


git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1415 4c0a9323-5329-0410-9bdc-e9ce6186880e

1 files changed, 21 insertions, 7 deletions

diff --git a/src/common/dwarf_cu_to_module.cc b/src/common/dwarf_cu_to_module.cc
index 4bd7bdd5..aaac058b 100644
--- a/src/common/dwarf_cu_to_module.cc
+++ b/src/common/dwarf_cu_to_module.cc
@@ -351,9 +351,15 @@ void DwarfCUToModule::GenericDIEHandler::ProcessAttributeString(
       break;
     case dwarf2reader::DW_AT_MIPS_linkage_name: {
       char* demangled = NULL;
+      int status = -1;
 #if !defined(__ANDROID__)
-      demangled = abi::__cxa_demangle(data.c_str(), NULL, NULL, NULL);
+      demangled = abi::__cxa_demangle(data.c_str(), NULL, NULL, &status);
 #endif
+      if (status != 0) {
+        cu_context_->reporter->DemangleError(data, status);
+        demangled_name_ = "";
+        break;
+      }
       if (demangled) {
         demangled_name_ = AddStringToPool(demangled);
         free(reinterpret_cast<void*>(demangled));
@@ -534,18 +540,19 @@ void DwarfCUToModule::FuncHandler::Finish() {
   // functions that were never used), but all the ones we're
   // interested in cover a non-empty range of bytes.
   if (low_pc_ < high_pc_) {
-    // Create a Module::Function based on the data we've gathered, and
-    // add it to the functions_ list.
-    scoped_ptr<Module::Function> func(new Module::Function);
     // Malformed DWARF may omit the name, but all Module::Functions must
     // have names.
+    string name;
     if (!name_.empty()) {
-      func->name = name_;
+      name = name_;
     } else {
       cu_context_->reporter->UnnamedFunction(offset_);
-      func->name = "<name omitted>";
+      name = "<name omitted>";
     }
-    func->address = low_pc_;
+
+    // Create a Module::Function based on the data we've gathered, and
+    // add it to the functions_ list.
+    scoped_ptr<Module::Function> func(new Module::Function(name, low_pc_));
     func->size = high_pc_ - low_pc_;
     func->parameter_size = 0;
     if (func->address) {
@@ -667,6 +674,13 @@ void DwarfCUToModule::WarningReporter::UnnamedFunction(uint64 offset) {
           filename_.c_str(), offset);
 }
 
+void DwarfCUToModule::WarningReporter::DemangleError(
+    const string &input, int error) {
+  CUHeading();
+  fprintf(stderr, "%s: warning: failed to demangle %s with error %d\n",
+          filename_.c_str(), input.c_str(), error);
+}
+
 void DwarfCUToModule::WarningReporter::UnhandledInterCUReference(
     uint64 offset, uint64 target) {
   CUHeading();