Re: [PATCH 1/3] rust: add userspace pointers

From: Kees Cook
Date: Sat Feb 10 2024 - 01:20:34 EST




On February 8, 2024 7:41:52 AM PST, Alice Ryhl <aliceryhl@xxxxxxxxxx> wrote:
>On Thu, Feb 8, 2024 at 4:35 PM Greg Kroah-Hartman
><gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>>
>> On Thu, Feb 08, 2024 at 01:53:20PM +0100, Alice Ryhl wrote:
>> > > Is some sort of `Debug` implementation useful?
>> >
>> > Leaking pointer addresses in logs is frowned upon in the kernel, so I
>> > don't think we should include that.
>>
>> s/frowned upon/forbidden/ :)
>
>:)
>
>> Along those lines, you all are tieing in the "I want to print a pointer,
>> so hash it properly before I do so" logic from rust like we have in c,
>> right? Ideally you'd use the same logic if at all possible.
>>
>> If not, that probably needs to be done so that you don't accidentally
>> start leaking things.
>
>I don't know what the status of this is. For anything I've added, I've
>just made it entirely impossible to print addresses, hashed or not.

Thank you! That is certainly the preferred[1] approach. :)

-Kees

[1] https://www.kernel.org/doc/html/next/process/deprecated.html#p-format-specifier

--
Kees Cook