Questions tagged [register]

Use this tag when asking *about* registers, their properties, existence, usage or limitations. Avoid using this tag just because registers are mentioned in the question.

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How are addresses calculated from the values in x86 segment registers?

How are the 16-bit values in segment registers used to represent large memory addresses? ES 0023 32bit 0(FFFFFFFF) CS 001B 32bit 0(FFFFFFFF) SS 0023 32bit 0(FFFFFFFF) DS 0023 32bit 0(FFFFFFFF) FS ...
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How can I step through instructions in IDA and know the current EIP?

import idaapi x=0 while x<10: idaapi.step_into() rv = idaapi.regval_t() idaapi.get_reg_val('EIP',rv) ea = rv.ival print hex(ea) x+=1 Hi. Here is a script to step-into 10 ...
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Is the value of EBP before the main function important?

So before we come to the main function, it looks we are in a function with a name __libc_start_main and before we come to our main function we obviously push EBP value in the stack ( the value of EBP ...
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How can an IA-32 program seemingly compiled with MSVC send its sole argument via EAX? [duplicate]

A C++ program I'm looking at appears to have been compiled with MSVC. It links to MSVCR100.dll, contains MSVC's security cookie code and uses the Microsoft mangling scheme. However, one of the ...
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Ollydbg: How to set a conditinal breakpoint for a register gets special value

I read this question about "set conditional break point on a register value" ; but its about setting a bp on special address! I want to set a bp when for example ECX == 12345678 , i can do this on ...
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How to access and modify data segment when doing hardware breakpoint crashes the application?

I want to modify the data segment in the x64_DBG, however, I don't know how to access it. lea r8,qword ptr ds:[7FEF0CA6AD8] In the above code, the address 7FEF0CA6AD8 is loaded in r8 register. I ...