linux-kernel - Re: [PATCH v6] rust: kernel: add support for bits/genmask macros

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <DAO1K5YIFVRH.31XI173DWYYX1@nvidia.com>
Date: Mon, 16 Jun 2025 23:52:54 +0900
From: "Alexandre Courbot" <acourbot@...dia.com>
To: "Daniel Almeida" <daniel.almeida@...labora.com>, "Boqun Feng"
 <boqun.feng@...il.com>
Cc: "Miguel Ojeda" <ojeda@...nel.org>, "Alex Gaynor"
 <alex.gaynor@...il.com>, "Gary Guo" <gary@...yguo.net>,
 Björn Roy Baron <bjorn3_gh@...tonmail.com>, "Benno Lossin"
 <benno.lossin@...ton.me>, "Andreas Hindborg" <a.hindborg@...nel.org>,
 "Alice Ryhl" <aliceryhl@...gle.com>, "Trevor Gross" <tmgross@...ch.edu>,
 "Danilo Krummrich" <dakr@...nel.org>, <linux-kernel@...r.kernel.org>,
 <rust-for-linux@...r.kernel.org>
Subject: Re: [PATCH v6] rust: kernel: add support for bits/genmask macros

On Mon Jun 16, 2025 at 11:45 PM JST, Daniel Almeida wrote:
>
>
>> On 16 Jun 2025, at 11:42, Daniel Almeida <daniel.almeida@...labora.com> wrote:
>> 
>> Hi Boqun,
>> 
>>> 
>>> We should tell/educate people to do the right thing, if a..b is not
>>> inclusive in Rust, then we should treat them as non-inclusive in Rust
>>> kernel code. Otherwise you create confusion for no reason. My assumption
>>> is that most people will ask "what's the right way to do this" first
>>> instead of replicating the old way.
>>> 
>>> Regards,
>>> Boqun
>>> 
>> 
>> This is just my opinion, of course:
>> 
>> I _hardly_ believe this will be the case. When people see genmask and two
>> numbers, they expect the range to be inclusive, full stop (at least IMHO). That's how it has
>> worked for decades, so it’s only natural to expect this behavior to transfer over.
>> 
>> However, I do understand and agree with your point, and I will change the
>> implementation here to comply. Perhaps we can use some markdown to alert users?
>> 
>> — Daniel
>
> Or better yet, perhaps we should only support a..=b.

... or just drop the ranges and do as Daniel initially did, using two
arguments. But I agree with Boqun that we should not deviate from the
official interpretation of ranges if we use them - the fact that `Range`
is exclusive on its upper bound is documented and a property of the type
itself.