Add new flag to allow granular control over the use of objdump.

This adds a new flag `enable_objdump_for_exploitability_` to the
MinidumpProcessor, which allows enabling objdump separately for crash
address fixups and for exploitability analysis, as the performance cost
of the exploitability analysis is significantly higher.

Change-Id: I667ffdce7cc0a970793f91413c3d2e3af93f4247
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/4507067
Reviewed-by: Ivan Penkov <ivanpe@google.com>
Reviewed-by: Ivan Penkov <ivanpe@chromium.org>

3 files changed, 21 insertions, 6 deletions

diff --git a/src/google_breakpad/processor/minidump_processor.h b/src/google_breakpad/processor/minidump_processor.h
index 137ef444..8475407e 100644
--- a/src/google_breakpad/processor/minidump_processor.h
+++ b/src/google_breakpad/processor/minidump_processor.h
@@ -126,8 +126,18 @@ class MinidumpProcessor {
   // does not exist or cannot be determined.
   static string GetAssertion(Minidump* dump);
 
+  // Sets the flag to enable/disable use of objdump during normal crash
+  // processing. This is independent from the flag for use of objdump during
+  // exploitability analysis.
   void set_enable_objdump(bool enabled) { enable_objdump_ = enabled; }
 
+  // Sets the flag to enable/disable use of objdump during exploitability
+  // analysis. This is independent from the flag for use of objdump during
+  // normal crash processing.
+  void set_enable_objdump_for_exploitability(bool enabled) {
+    enable_objdump_for_exploitability_ = enabled;
+  }
+
  private:
   StackFrameSymbolizer* frame_symbolizer_;
   // Indicate whether resolver_helper_ is owned by this instance.
@@ -138,9 +148,15 @@ class MinidumpProcessor {
   // memory corruption issue.
   bool enable_exploitability_;
 
-  // This flag permits the exploitability scanner to shell out to objdump
-  // for purposes of disassembly.
+  // This flag permits the processor to shell out to objdump for purposes of
+  // disassembly during normal crash processing, but not during exploitability
+  // analysis.
   bool enable_objdump_;
+
+  // This flag permits the exploitability scanner to shell out to objdump for
+  // purposes of disassembly. This results in significantly more overhead than
+  // the enable_objdump_ flag.
+  bool enable_objdump_for_exploitability_;
 };
 
 }  // namespace google_breakpad
diff --git a/src/processor/exploitability_unittest.cc b/src/processor/exploitability_unittest.cc
index 5f8cee0a..09e4690d 100644
--- a/src/processor/exploitability_unittest.cc
+++ b/src/processor/exploitability_unittest.cc
@@ -84,7 +84,7 @@ ExploitabilityFor(const string& filename) {
   SimpleSymbolSupplier supplier(TestDataDir() + "/symbols");
   BasicSourceLineResolver resolver;
   MinidumpProcessor processor(&supplier, &resolver, true);
-  processor.set_enable_objdump(true);
+  processor.set_enable_objdump_for_exploitability(true);
   ProcessState state;
 
   string minidump_file = TestDataDir() + "/" + filename;
diff --git a/src/processor/minidump_processor.cc b/src/processor/minidump_processor.cc
index 5ba6ff4f..f7d877c6 100644
--- a/src/processor/minidump_processor.cc
+++ b/src/processor/minidump_processor.cc
@@ -375,9 +375,8 @@ ProcessResult MinidumpProcessor::Process(
   // rating.
   if (enable_exploitability_) {
     scoped_ptr<Exploitability> exploitability(
-        Exploitability::ExploitabilityForPlatform(dump,
-                                                  process_state,
-                                                  enable_objdump_));
+        Exploitability::ExploitabilityForPlatform(
+          dump, process_state, enable_objdump_for_exploitability_));
     // The engine will be null if the platform is not supported
     if (exploitability != NULL) {
       process_state->exploitability_ = exploitability->CheckExploitability();