linux-kernel - Re: [PATCH v4 4/7] rust: str: make `from_bytes_with_nul_unchecked

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] [day] [month] [year] [list]

Message-Id: <DAQ5P0NPCHP4.1FJ30U8EW3JZ2@nvidia.com>
Date: Thu, 19 Jun 2025 11:32:39 +0900
From: "Alexandre Courbot" <acourbot@...dia.com>
To: "Benno Lossin" <lossin@...nel.org>, "Danilo Krummrich"
 <dakr@...nel.org>, "Miguel Ojeda" <ojeda@...nel.org>, "Alex Gaynor"
 <alex.gaynor@...il.com>, "Boqun Feng" <boqun.feng@...il.com>, "Gary Guo"
 <gary@...yguo.net>, Björn Roy Baron
 <bjorn3_gh@...tonmail.com>, "Andreas Hindborg" <a.hindborg@...nel.org>,
 "Alice Ryhl" <aliceryhl@...gle.com>, "Trevor Gross" <tmgross@...ch.edu>
Cc: <rust-for-linux@...r.kernel.org>, <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v4 4/7] rust: str: make
 `from_bytes_with_nul_unchecked_mut` const

On Thu Jun 19, 2025 at 6:16 AM JST, Benno Lossin wrote:
> On Mon Jun 16, 2025 at 5:34 AM CEST, Alexandre Courbot wrote:
>> This method was probably kept non-const due to the absence of the
>> `const_mut_refs` feature, but it has been enabled since the introduction
>> of this code (and stabilized with Rust 1.83). Thus, make it const to
>> match its non-const counterpart.
>>
>> Signed-off-by: Alexandre Courbot <acourbot@...dia.com>
>
> Ah on second thought, this and the next two patches are a bit redundant,
> since Tamir has a series [1] removing our `CStr` and using the one from
> `core`.
>
> If you need this *now* and can't wait for Tamir's series to land, then
> we can do this and the other two changes, but othrwise I'd just use
> `CStr` from `core`.
>
> It does seem like you need `&mut CStr`, which the one in `core` doesn't
> seem to provide... But our `CStr` also doesn't have `IndexMut`, so...
> how are you using it? Giving it to a C API?
>
> In that case I don't know what we should do about [1]... @Miguel?
>
> [1]: https://lore.kernel.org/all/20250530-cstr-core-v11-0-cd9c0cbcb902@gmail.com

Let's drop this part (patches 4..=7) for now to avoid interfering with
Tamir's work - the CString implementation was more of a drive-by, the
container types are more important to support. I will revisit after
Tamir's series lands, if needed.

As Danilo took patches 1 and 3, this just leaves patch 2 to be picked
up if it looks ok.