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Index > Main > JUMP instruction bug I've seen for me
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Diicorp95



Joined: 18 Mar 2021
Posts: 3
Location: Bristol, United Kingdom
Diicorp95
Hello, people! Do you have any idea why

Code:
jmp 0x00007E00


compiles into

Code:
jmp 0x00000200


?

I'm sure that I did everything OK. Sad
Post 18 Mar 2021, 13:17
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Diicorp95



Joined: 18 Mar 2021
Posts: 3
Location: Bristol, United Kingdom
Diicorp95
I think that's because of org 0x7C00, because 0x7E00 - 0x7C00 = 0x0200...
Post 18 Mar 2021, 13:53
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 18266
Location: In your JS exploiting you and your system
revolution
All jmp and call instructions are IP relative when you use an immediate operand.

Everything is as expected.
Post 18 Mar 2021, 16:20
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Diicorp95



Joined: 18 Mar 2021
Posts: 3
Location: Bristol, United Kingdom
Diicorp95
revolution wrote:
All jmp and call instructions are IP relative when you use an immediate operand.

Everything is as expected.


I've tested it on zero-filled IP.
Post 19 Mar 2021, 15:15
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