<rdar://problem/13590152>

Providing a dummy RegisterContext to secure against faulty Python OS plugins that do not return a valid RegisterContext
The RegisterContextDummy exports a PC with a constant 0xFFFFFFFFFFFFFFFF value

llvm-svn: 180033

1 files changed, 8 insertions, 0 deletions

diff --git a/lldb/source/Plugins/OperatingSystem/Python/OperatingSystemPython.cpp b/lldb/source/Plugins/OperatingSystem/Python/OperatingSystemPython.cpp
index 6e2aadb7fde..a7aaedb9a0c 100644
--- a/lldb/source/Plugins/OperatingSystem/Python/OperatingSystemPython.cpp
+++ b/lldb/source/Plugins/OperatingSystem/Python/OperatingSystemPython.cpp
@@ -33,6 +33,7 @@
 #include "lldb/Target/ThreadList.h"
 #include "lldb/Target/Thread.h"
 #include "Plugins/Process/Utility/DynamicRegisterInfo.h"
+#include "Plugins/Process/Utility/RegisterContextDummy.h"
 #include "Plugins/Process/Utility/RegisterContextMemory.h"
 #include "Plugins/Process/Utility/ThreadMemory.h"
 
@@ -333,6 +334,13 @@ OperatingSystemPython::CreateRegisterContextForThread (Thread *thread, addr_t re
             }
         }
     }
+    // if we still have no register data, fallback on a dummy context to avoid crashing
+    if (!reg_ctx_sp)
+    {
+        if (log)
+            log->Printf ("OperatingSystemPython::CreateRegisterContextForThread (tid = 0x%" PRIx64 ") forcing a dummy register context", thread->GetID());
+        reg_ctx_sp.reset(new RegisterContextDummy(*thread,0,target.GetArchitecture().GetAddressByteSize()));
+    }
     return reg_ctx_sp;
 }