[LLVMdev] DataFlowSanitizer using wrong memory layout

[Peter Collingbourne]

On Thu, Jan 15, 2015 at 10:58:42AM -0800, machiry aravind wrote:
> Hi all,
> 
> Any one tried using DataFlowSanitizer on Linux x86_64? 

DFSan is developed and tested regularly on Linux x86_64.

> I tried on:
>  3.13.0-44-generic #73~precise1-Ubuntu SMP Wed Dec 17 00:39:15 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
> 
> It assumes wrong memory layout and remaps application code segment as shadow memory, thus causing SIGSEV (Segmentation fault).
> 
> 
> Is this know? and fix under way?

I've found this to occur if the application is not built as a
position-independent executable, but we've explicitly taught the Clang
driver to produce position-independent executables if DFSan is enabled,
so it isn't clear why this might be happening to you.

How exactly are you building your application? Does a simple C hello world
program work? Do the tests (make check-dfsan) pass?

Thanks,
-- 
Peter