Why not INCREMET VALUE

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Everhest

Joined: 26 Jun 2008
Posts: 83
Location: Russia

Everhest 25 Jan 2009, 10:35

Hi. In this function not increment value:

Code:

proc Manager.New
        inc     [dm.count]
        stdcall MemoryInit, [id.array.heap], sizeof.ITEM_DOWNLOAD
        mov     ecx, id.array.point
        mov     [ecx], eax
     thread_create:
        xor     eax, eax
        invoke  CreateThread, eax, 1024*1024*32, ThreadFun, eax, eax, id.thread
        mov     [id.thread], eax
        .if     eax = 0
                invoke  GetLastError
                stdcall ErrorMessage, eax
        .endif
     copy_points:
        cld
        mov     esi, id.array
        imul    edi, [dm.count], 8
        add     edi, dm.items
        movsd
        movsd
     copy_data:
        mov     eax, [dm.count]
        mov     [id.id], eax
        stdcall MemoryCopy, [id.array.point], id, sizeof.ITEM_DOWNLOAD
        ret
endp

Please help me!!!

Description:		Download
Filename:	manager.rar
Filesize:	5.5 KB
Downloaded:	231 Time(s)

_________________
Forgive for my bad english, I from russia...

25 Jan 2009, 10:35

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20446
Location: In your JS exploiting you and your system

revolution 25 Jan 2009, 10:41

What doesn't increment? Is it dm.count that doesn't increment?

25 Jan 2009, 10:41

Everhest

Joined: 26 Jun 2008
Posts: 83
Location: Russia

Everhest 25 Jan 2009, 11:01

Yes, of course dm.count, if call of my proc ShowDword, dm.count to see not increment!!!

25 Jan 2009, 11:01

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20446
Location: In your JS exploiting you and your system

revolution 25 Jan 2009, 11:27

Maybe because you overwrite the count value:

Code:

struct        ARRAY
       heap            dd ?
        point           dd ?
ends

struct DOWNLOAD_MANAGMENT
       items           ARRAY
       count           dd 0
        socket          SOCKET_INFO
ends

...

  mov     esi, id.array
       imul    edi, [dm.count], 8
  add     edi, dm.items ;<--- dm.count follows this address
        movsd
       movsd

25 Jan 2009, 11:27

Everhest

Joined: 26 Jun 2008
Posts: 83
Location: Russia

Everhest 25 Jan 2009, 12:09

hm... yes... i'm must moved 2 dword in pointers on address items.point

thank you!

25 Jan 2009, 12:09

Everhest

Joined: 26 Jun 2008
Posts: 83
Location: Russia

Everhest 25 Jan 2009, 12:30

So it is correct?

Code:

        cld
        mov     esi, id.array
        imul    ecx, [dm.count], 8
        lea     edi, [dm.items]
        add     [edi], ecx
        movsd
        movsd

25 Jan 2009, 12:30

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20446
Location: In your JS exploiting you and your system

revolution 25 Jan 2009, 12:34

Your current setup mean that you are copying data into a dm structure but the structure is not large enough to hold all of your data so you start to overwrite whatever comes after the dm.item member.

I think you should consider using a different way to store your array.

Maybe you can try using a linked list. Just store the head of the list in the dm structure and then allocate each new item dynamically with each one linking to the next.

25 Jan 2009, 12:34

Everhest

Joined: 26 Jun 2008
Posts: 83
Location: Russia

Everhest 25 Jan 2009, 12:45

Ok... Thank you!

25 Jan 2009, 12:45

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