linux-kernel - Re: [PATCH 1/3] rust: error: improve `Error::from

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: <DCFR8DTO39D2.1RMIDS2RUJ3H9@nvidia.com>
Date: Sat, 30 Aug 2025 21:17:57 +0900
From: "Alexandre Courbot" <acourbot@...dia.com>
To: "Miguel Ojeda" <ojeda@...nel.org>, "Alex Gaynor" <alex.gaynor@...il.com>
Cc: "Boqun Feng" <boqun.feng@...il.com>, "Gary Guo" <gary@...yguo.net>,
 Björn Roy Baron <bjorn3_gh@...tonmail.com>, "Benno Lossin"
 <lossin@...nel.org>, "Andreas Hindborg" <a.hindborg@...nel.org>, "Alice
 Ryhl" <aliceryhl@...gle.com>, "Trevor Gross" <tmgross@...ch.edu>, "Danilo
 Krummrich" <dakr@...nel.org>, <rust-for-linux@...r.kernel.org>,
 <linux-kernel@...r.kernel.org>, <patches@...ts.linux.dev>
Subject: Re: [PATCH 1/3] rust: error: improve `Error::from_errno`
 documentation

On Sat Aug 30, 2025 at 4:22 AM JST, Miguel Ojeda wrote:
> This constructor is public since commit 5ed147473458 ("rust: error:
> make conversion functions public"), and we will refer to it from the
> documentation of `to_result` in a later commit.
>
> Thus improve its documentation, including adding examples.
>
> Signed-off-by: Miguel Ojeda <ojeda@...nel.org>

This reads very smoothly!

Reviewed-by: Alexandre Courbot <acourbot@...dia.com>

> ---
>  rust/kernel/error.rs | 19 +++++++++++++++++--
>  1 file changed, 17 insertions(+), 2 deletions(-)
>
> diff --git a/rust/kernel/error.rs b/rust/kernel/error.rs
> index a41de293dcd1..c415c3d3a3b6 100644
> --- a/rust/kernel/error.rs
> +++ b/rust/kernel/error.rs
> @@ -101,8 +101,23 @@ macro_rules! declare_err {
>  impl Error {
>      /// Creates an [`Error`] from a kernel error code.
>      ///
> -    /// It is a bug to pass an out-of-range `errno`. `EINVAL` would
> -    /// be returned in such a case.
> +    /// `errno` must be within error code range (i.e. `>= -MAX_ERRNO && < 0`).
> +    ///
> +    /// It is a bug to pass an out-of-range `errno`. [`code::EINVAL`] is returned in such a case.
> +    ///
> +    /// # Examples
> +    ///
> +    /// ```
> +    /// assert_eq!(Error::from_errno(-1), EPERM);
> +    /// assert_eq!(Error::from_errno(-2), ENOENT);

Small nit: this leaves a tiny chance of misunderstanding that this
function actually expects literal negative integers. How about using
e.g. `bindings::EPERM` instead of `-1`?