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Quell
December 30th, 2004, 10:49
Hey.
i have a problem.
Olly debug gives me access violation.Why?
My os is windows xp pro. No SP's installed
when i debug an application in olly debug i constanly get access violation at 0x000000 . I figures this has something to do with how the memroy is being open to be read? Or trying to delete a pointer that has already been deleted?
So i figure this is a problem on behalf of the debugee.
I read some web sites and i found a way to stop this from being a problem(unchecking break on access violations in debug options).
But i was wondereing if it is Olly causing these problem? Or was i right and it is a flaw in the programing of the debugee?

evlncrn8
December 30th, 2004, 11:51
i doubt its olly causing it, i also doubt its a flaw in the programming of olly, some protections use exceptions to alter code flow etc.. and how can a memory access violation at 0x00000000 be deleting a pointer thats already been deleted, stop guessing, do some research, answer ur own questions

klier
December 30th, 2004, 12:41
http://www.cit.gu.edu.au/~anthony/icons/large/troll.jpg
Regards,

Quell
December 30th, 2004, 13:02
i did do research, and access violation can happen when a pointer is being re-deleted....
the 0x0000000 screwed me up becuase it is not in the range where the program is running, and the olly says that the violation is at that adress.
is that possible or is it a bug?

evlncrn8
December 30th, 2004, 18:24
it is in the range where the program is running, but its a protected memory area that causes an access violation when accessed.. like

xor eax,eax ; eax= 0
mov eax,[eax] = access memory area 0.. instant crash

the program could be deliberately causing exceptions (some protections do this),
so sure its possible, as to it being a bug.. doubtful.. if the program runs if you dont debug it then its probably some protection check causing the exception, if it doesnt run when you dont debug it then it could be a bug.. the bug however is not in olly