[OffTopic] A vulnerability postmortem on Network Security Services

[Paulo Pinto]

On Friday, 3 December 2021 at 12:27:11 UTC, Ola Fosheim Grøstad 
wrote:
> On Friday, 3 December 2021 at 12:08:59 UTC, Paulo Pinto wrote:
>> Note that on platforms like iOS and Android, going forward, 
>> those considerations don't matter at the language level, 
>> because the whole stack is using it.
>
> So you are saying that this will be required and not an option 
> once all CPUs are capable? Right now it seems to be opt-in?
> ...

Yes that is the whole point.

> You can use the framework's sxadm command to enable and disable 
> security extensions for selected binaries and to manage their 
> properties.

https://docs.oracle.com/cd/E37838_01/html/E61021/sysauth-secext.html#OSSADsysauth-secext

So on Solaris, the admin gets to say if the OS runs the process 
under hardware memory tagging or not.

On Android,

> Starting in Android 11, for 64-bit processes, all heap 
> allocations have an implementation defined tag set in the top 
> byte of the pointer on devices with kernel support for ARM 
> Top-byte Ignore (TBI). Any application that modifies this tag 
> is terminated when the tag is checked during deallocation. This 
> is necessary for future hardware with ARM Memory Tagging 
> Extension (MTE) support.
>....
> TBI requires a compatible kernel that correctly handles tagged 
> pointers passed from userspace. Android Common Kernels from 
> 4.14 (Pixel 4) and higher feature the required TBI patches.

https://source.android.com/devices/tech/debug/tagged-pointers

Note the "all heap allocations" on the documentation and it being 
enabled on Pixel 4 and later devices.

You can guess similar documentation for the other links I 
provided earlier.