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Index > Compiler Internals > My favorite DLL won't initialize when I use 1.69.24 or .25

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farrier



Joined: 26 Aug 2004
Posts: 274
Location: North Central Mississippi
farrier
Attached is a test file and trm.dll, along with the fasm.exe's that I tested with. TRM is the Tsunami Record Manager, a freely distributed, non-open sourced "data base" package--no longer supported.

When using 1.69.20 and .22 the program assembles and runs fine. When using .24 or .25, the program assembles but won't properly initialize the dll. In Olly 2 it seems to enter the dll at the wrong place, but I'm not sure. One thing about the dll, it is compressed or protected in such a way that Olly 1 would give a message that the entry point was outside the memory space, or something like that.

This had me scratching my head for a few hours.

Thanks in advance,

farrier


Description:
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Filename: TestTRM.7z
Filesize: 152.82 KB
Downloaded: 442 Time(s)


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Post 19 Oct 2010, 12:36
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
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revolution
There appears to be new flags set:

IMAGE_DLLCHARACTERISTICS_NX_COMPAT 0x0100 (offset PE_Header:0x5e)

and

IMAGE_FILE_RELOCS_STRIPPED 0x0001 (offset PE_Header:0x16)

Both introduced in 1.69.23
Post 19 Oct 2010, 13:01
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
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revolution
My guess is that the DEP is the problem. Perhaps the DLL writes some code to the stack?

Try either/both 1) manually flipping the NX bit in the exe 2) turning off DEP in your OS for the test exe.
Post 19 Oct 2010, 13:20
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farrier



Joined: 26 Aug 2004
Posts: 274
Location: North Central Mississippi
farrier
Programs using this DLL and the "Pro" version have been running on OS's from Win 95 thru Win 7 without a hiccup for 9 years now. So it is something that the fasm is doing to the .exe file that makes my Win Vista 64 unhappy.

I'll try the NX bit this evening! Thanks.

farrier

_________________
Some Assembly Required
It's a good day to code!
U.S.Constitution; Bill of Rights; Amendment 1:
... the right of the people peaceably to assemble, ...
The code is dark, and full of errors!
Post 19 Oct 2010, 19:29
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Tomasz Grysztar
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Joined: 16 Jun 2003
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Tomasz Grysztar
I did add the "NX-aware" setting since with fasm you specify "executable" flag for sections, which really makes full sense only when you have NX enabled. However if that code tries to execute some code on stack, that would really be a problem, since there is no way of defining PE stack as "executable".
Maybe I should add "NX" as another flag for "format PE" declaration.
Post 21 Oct 2010, 09:10
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
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revolution
Tomasz Grysztar wrote:
Maybe I should add "NX" as another flag for "format PE" declaration.
Yes. I think it is needed.

farrier: Was the NX bit the problem for you?
Post 21 Oct 2010, 09:28
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farrier



Joined: 26 Aug 2004
Posts: 274
Location: North Central Mississippi
farrier
Tomasz & revolution,

It does indeed appear to be DEP. Things changed for me with 1.69.24 & .25 and the only differences in the .exe's were:

Time and Date: makes sense
Characteristics: .24 & .25 have IMAGE_FILE_RELOCS_STRIPPED set ??
Checksum: again, makes sense
DllCharacteristics: word at 0xDE, 0xDF in the .exe, .24 & .25 are set to
IMAGE_DLLCHARACTERISTICS_NX_COMPAT - 0x0100 which is
"The image is compatible with data execution prevention (DEP)."

Changing 0x0100 to 0x0000 allowed the program to run without problems, the IMAGE_FILE_RELOCS_STRIPPED bit being set or cleared didn't seem to make a difference. I haven't figured out what this does!!

So for now, I'll continue to use the latest version of the fasm and clear "The bit that makes a difference!"

Thanks again for your help!

farrier

_________________
Some Assembly Required
It's a good day to code!
U.S.Constitution; Bill of Rights; Amendment 1:
... the right of the people peaceably to assemble, ...
The code is dark, and full of errors!
Post 21 Oct 2010, 18:53
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baldr



Joined: 19 Mar 2008
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baldr
farrier,

editbin /nxcompat:no can be used to automate bit reset.

IMAGE_FILE_RELOCS_STRIPPED indicates that base relocations (usually .reloc section, pointed by DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC] element of optional header field) are absent. Such PE can't be relocated and can be loaded only at its preferred image base. Actually loader ignores this flag and looks for valid DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC] entry.
Post 21 Oct 2010, 21:36
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farrier



Joined: 26 Aug 2004
Posts: 274
Location: North Central Mississippi
farrier
baldr,

I'll study, learn, and use!

Thanks,

farrier

_________________
Some Assembly Required
It's a good day to code!
U.S.Constitution; Bill of Rights; Amendment 1:
... the right of the people peaceably to assemble, ...
The code is dark, and full of errors!
Post 22 Oct 2010, 04:11
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
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revolution
Tomasz Grysztar wrote:
Maybe I should add "NX" as another flag for "format PE" declaration.
Is this flag in the planning for a future release?
Post 25 Dec 2010, 07:19
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farrier



Joined: 26 Aug 2004
Posts: 274
Location: North Central Mississippi
farrier
Any update on the NZ flag?

farrier

_________________
Some Assembly Required
It's a good day to code!
U.S.Constitution; Bill of Rights; Amendment 1:
... the right of the people peaceably to assemble, ...
The code is dark, and full of errors!
Post 04 Apr 2011, 06:59
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Tomasz Grysztar
Assembly Artist


Joined: 16 Jun 2003
Posts: 7709
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Tomasz Grysztar
I have added the "NX" flag in 1.69.32 release. Sorry for delay, I just forgot about it until now.
Post 23 Jul 2011, 22:45
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farrier



Joined: 26 Aug 2004
Posts: 274
Location: North Central Mississippi
farrier
Tomasz,

Thank you for your continued, excellent efforts for us!!!

farrier

_________________
Some Assembly Required
It's a good day to code!
U.S.Constitution; Bill of Rights; Amendment 1:
... the right of the people peaceably to assemble, ...
The code is dark, and full of errors!
Post 24 Jul 2011, 16:08
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madmatt



Joined: 07 Oct 2003
Posts: 1045
Location: Michigan, USA
madmatt
I'm having a similar problem with using the "LoadLibrary" function with an fasm dll (which the latest fasmw version [1.69.32] doesn't seem to fix.). It seems to be trying to initialize the dll in the wrong place. Some Examples are below, the one in 2008 runs good, the later one gives me an error.


Description: Fasm DLL Examples
Download
Filename: ShowBit.zip
Filesize: 18.73 KB
Downloaded: 282 Time(s)


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Post 04 Aug 2011, 14:34
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madmatt



Joined: 07 Oct 2003
Posts: 1045
Location: Michigan, USA
madmatt
madmatt wrote:
I'm having a similar problem with using the "LoadLibrary" function with an fasm dll (which the latest fasmw version [1.69.32] doesn't seem to fix.). It seems to be trying to initialize the dll in the wrong place. Some Examples are below, the one in 2008 runs good, the later one gives me an error.


Hmmmm, appears no one else is having this problem?

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Post 27 Aug 2011, 11:27
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