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Nameless



Joined: 30 Apr 2010
Posts: 95
Nameless
when i tried to put 'lpResource db 'SETTINGS',0' right before .code section, like this
Code:
lpResource    db      'SETTINGS',0
.code
 Start:
    


the output is 424+ kb :S

when i put it the same line, in the same app, but anywhere else (at the very top of the .data section for example) the output is the normal size
am i missing something here?
i can show anyone on teamviewer, just drop me a pm
Post 06 May 2010, 05:14
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 17271
Location: In your JS exploiting you and your system
revolution
Mixing initialised data with uninitialised data.
Code:
.data
rb 1000000 ;uninitialised
db 'X' ;initialised    
Code:
.data
db 'X' ;initialised
rb 1000000 ;uninitialised    
One section is 1 byte long and the other is 1000001 bytes long. The PE format can store implicit zeros at the end of a section but not at the beginning. You should either put all initialised data into a separate section, or put all initialised data together at the start of a section.
Post 06 May 2010, 05:40
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baldr



Joined: 19 Mar 2008
Posts: 1651
baldr
revolution wrote:
One section is 1 byte long and the other is 1000001 bytes long.
This can be misleading: both sections are 1000001 bytes long, they differ only in their representation in PE. Wink
Post 06 May 2010, 05:46
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 17271
Location: In your JS exploiting you and your system
revolution
Yes, baldr is correct. When the exe is loaded into memory the section sizes will be the same. But on disk the stored section sizes differ greatly.
Post 06 May 2010, 08:29
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Nameless



Joined: 30 Apr 2010
Posts: 95
Nameless
oh
ok, thanks for the info, also sorry for the mis-understanding
Post 06 May 2010, 09:38
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