Re: change page protection, how to

Hi,
I have a very small stub of code (not a virus)
that needs to patch some functions, which reside
on read only pages... by patching I mean
overwrite the begining of the function with a
a 'jmp' to my stub... is there an easy way to
unprotect that page? or do I really have to
call the kernel (windows) to do it?
Thanks, any pointer appreciated

If you are running your code in user mode,
under windows and a page is read only,
then the only way to change that is by
the kernel. If it refuses to do so, then it's
not possible to circumwent it from user mode.

The idea behind hardware protection is to
protect the whole system (inclusive all running
programs) from user mode programs that
want to change something.

Viktor

ps:
Overwriting a function is not a nice way to
patch an application. There are standard
hooks and call tables. For patching dlls,
you can use a wrapper dll linking back
to the original.

.

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