support /clr:safe images

_From [bruen...@google.com](https://code.google.com/u/109494838902877177630/) on July 22, 2013 16:31:34_

/clr:safe images use a 32-bit PE that is modified when loaded on 64-bit kernel to be a 64-bit PE. Our injection bitwidth check gets this wrong, of course.

Furthermore, after disabling the check, bin64/drrun successfully injects but then the image entry point is not properly tweaked by mscoree, or something -- I haven't diagnosed fully. The symptoms are an app crash right up front.

This issue covers both detecting in the front-end launchers and running properly once injected.

My test app here is PCMark7Cmd.exe.

Need an elevated shell, else:
ERROR: Failed to create process for "c:\Program Files\Futuremark\PCMark 7\bin\PCMark7Cmd.exe": The requested operation requires elevation.

% bin32/drrun -v -- c:/Program\ Files/Futuremark/PCMark\ 7/bin/PCMark7Cmd.exe
INFO: targeting application: "c:\Program Files\Futuremark\PCMark 7\bin\PCMark7Cmd.exe"
INFO: app cmdline: "c:/Program Files/Futuremark/PCMark 7/bin/PCMark7Cmd.exe"
INFO: created child with pid 4204 for c:\Program Files\Futuremark\PCMark 7\bin\PCMark7Cmd.exe
ERROR: unable to inject: did you forget to run drconfig first?

10:41 AM ~/DynamoRIO-Windows-4.1.0-4
% bin64/drrun -v -- c:/Program\ Files/Futuremark/PCMark\ 7/bin/PCMark7Cmd.exe
INFO: targeting application: "c:\Program Files\Futuremark\PCMark 7\bin\PCMark7Cmd.exe"
INFO: app cmdline: "c:/Program Files/Futuremark/PCMark 7/bin/PCMark7Cmd.exe"
INFO: created child with pid 0 for c:\Program Files\Futuremark\PCMark 7\bin\PCMark7Cmd.exe
ERROR: Target process c:\Program Files\Futuremark\PCMark 7\bin\PCMark7Cmd.exe is for the wrong architecture

Custom build w/o the arch check:
% bin64/drrun -debug -v -msgbox_mask 15 -stderr_mask 15 -- c:/Program\ Files/Futuremark/PCMark\ 7/bin/PCMark7Cmd.exe
INFO: targeting application: "c:\Program Files\Futuremark\PCMark 7\bin\PCMark7Cmd.exe"
INFO: app cmdline: "c:/Program Files/Futuremark/PCMark 7/bin/PCMark7Cmd.exe"
INFO: created child with pid 788 for c:\Program Files\Futuremark\PCMark 7\bin\PCMark7Cmd.exe
INFO: waiting forever for app to exit...

Segmentation fault

ASYNCH intercepted exception in thread 2092 at pc 0x00000000206f10c1
exception code = 0x00000000c0000005, ExceptionFlags=0x0000000000000000
record=0x0000000000000000, params=2
PC 0x00000000206f10c1 tried to read address 0x00000000010021f4

Exception is in this fragment:
Fragment 5, tag 0x0000000000c001ee, flags 0x1000030, shared, size 21:
[PCMark7Cmd.exe]
0x00000000206f10b8 65 48 89 0c 25 30 16 mov %rcx -> %gs:0x00001630
00 00
0x00000000206f10c1 48 8b 0d 2c 11 91 e0 mov 0x00000000010021f4 -> %rcx
0x00000000206f10c8 e9 b3 2a ff ff jmp $0x00000000206e3b80
-------- exit stub 0: -------- type: indjmp

interp: start_pc = 0x0000000000c001ee
0x0000000000c001ee ff 25 00 20 40 00 jmp 0x00000000010021f4
end_pc = 0x0000000000c001f4

0x0000000000bc0000-0x0000000000c4dfff PCMark7Cmd.exe entry=0x0000000000000000 count=-1

That's the executable entry point, which should have been modified to point
at mscoree!_CorExeMain, or at least that's how stuff worked years ago.
Needs further investigation.

More info on the PE header: it's a PE32 header, modified by the kernel if mapped as an image (even w/ just DRload) to be a PE32+ header and placed in a non-WOW64 (i.e., native 64-bit) process if used in CreateProcess, but of course not modified if mapped as a non-image.

_Original issue: http://code.google.com/p/dynamorio/issues/detail?id=1224_