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REAP
November 7th, 2013, 22:53
Hello,

I have a question about conditional BP's

Say I have the following:
Code:
Call EAX


I can place conditional BP e.g. where EAX=='some value'

But say I want to identify where EAX is being set to 'some value', what options do I have?

Essentially I want to be able to place a conditional BP on a register, but that doesn't appear to be possible. Are there any plugins that provide this function?

Cheers

disavowed
November 8th, 2013, 11:42
You can use OllyDbg's conditional run trace for this.

REAP
November 8th, 2013, 23:40
Run trace does look to be the answer.

However when I try to use 'trace into' from OEP the app abends.

'Trace over' doesn't abend, but the condition is not being triggered.

If I set a BP before the area of interest, and run the app until the BP, and then try using run trace, similar behaviour. 'Trace over' doesn't abend, but does not break on condition.

'Trace into' sets the CPU usage to 100% and the app does not behave normally.

Have you had any experience with these types of issues?