CPL and RPL

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appusajeev
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Joined: Mon Aug 01, 2011 7:10 am

CPL and RPL

Post by appusajeev »

If CPL =3 , can we set RPL = 0 to access a segment?
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iansjack
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Re: CPL and RPL

Post by iansjack »

I presume that you are referring to a data segment? From the Intel manual:

"That is, if the RPL of a segment selector is numerically greater than the CPL, the RPL overrides the CPL, and vice versa."

So if the DPL is less than 3 then an RPL of 0 makes no difference as it doesn't override the CPL.
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