Re: [PATCH v2] rust: net: netlink: Migrate to zerocopy's IntoBytes

From: Alexandre Courbot

Date: Sun Sep 13 2026 - 22:25:58 EST


On Sun Sep 13, 2026 at 11:18 AM JST, Sagar Taunk wrote:
> Replace the kernel's own `transmute::FromBytes` and `AsBytes` traits
> with their zerocopy equivalents. Specifically, this updates
> `GenlMsg::put` to rely on `IntoBytes` for converting attributes into
> byte slices.
>
> Also, add `Immutable` trait bound on `GenlMsg::put` as zerocopy
> splits the `no interior mutability` guarantee that `AsBytes` bundled
> together.
>
> Link: https://github.com/Rust-for-Linux/linux/issues/1241
> Signed-off-by: Sagar Taunk <sagartaunk@xxxxxxxxx>
> ---
> v2: Split into a separate patch per Shashiko's review; validates the
> attribute length with c_int::try_from() instead of casting with `as`.
>
> rust/kernel/net/netlink.rs | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/rust/kernel/net/netlink.rs b/rust/kernel/net/netlink.rs
> index 22ef3dde36fa..3c2b142a7402 100644
> --- a/rust/kernel/net/netlink.rs
> +++ b/rust/kernel/net/netlink.rs
> @@ -12,11 +12,12 @@
> alloc::{self, AllocError},
> error::to_result,
> prelude::*,
> - transmute::AsBytes,
> types::Opaque,
> ThisModule,
> };
>
> +use zerocopy::{Immutable, IntoBytes};

Please use the vertical import style as per the guidelines [1].

With that,

Reviewed-by: Alexandre Courbot <acourbot@xxxxxxxxxx>

[1] https://docs.kernel.org/rust/coding-guidelines.html#imports