Re: [PATCH v9 23/42] Documentation/x86: Add CET shadow stack description
From: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
Date: 2023-07-06 16:59:55
Also in:
linux-arch, linux-doc, linux-mm, lkml
On Thu, 2023-07-06 at 15:24 +0100, Mark Brown wrote:
On Thu, Jul 06, 2023 at 02:14:40PM +0100, szabolcs.nagy@arm.com wrote:quoted
The 07/05/2023 20:29, Mark Brown wrote:quoted
quoted
Push and pop are one control, you get both or neither.quoted
gcspopm is always available (esentially *ssp++, this is used for longjmp).Ah, sorry - I misremembered there. You're right, it's only push that we have control over.
Ah, ok! So if you are not planning to enable the push mode then the features are pretty well aligned, except: - On x86 it is possible to switch stacks without leaving a token behind. - The GCSPOPM/INCSSP looping may require longer loops on ARM because it only pops one at at time. If you are not going to use GCSPUSHM by default, then I think we *should* be able to have some unified set of rules for developers for glibc behaviors at least.