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Message-ID: <a7f91ee5-ecd4-4446-9de7-3902763c0058@suse.de>
Date: Tue, 27 Feb 2024 11:05:22 +0100
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Subject: Re: [PATCH v2 1/4] rust: uaccess: add userspace pointers
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To: Alice Ryhl <aliceryhl@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
 =?UTF-8?Q?Arve_Hj=C3=B8nnev=C3=A5g?= <arve@android.com>,
 Todd Kjos <tkjos@android.com>, Martijn Coenen <maco@android.com>,
 Joel Fernandes <joel@joelfernandes.org>, Carlos Llamas
 <cmllamas@google.com>, Suren Baghdasaryan <surenb@google.com>,
 Arnd Bergmann <arnd@arndb.de>, linux-mm@kvack.org,
 linux-kernel@vger.kernel.org, rust-for-linux@vger.kernel.org,
 Christian Brauner <brauner@kernel.org>, Miguel Ojeda <ojeda@kernel.org>,
 Alex Gaynor <alex.gaynor@gmail.com>,
 Wedson Almeida Filho <wedsonaf@gmail.com>, Boqun Feng
 <boqun.feng@gmail.com>, Gary Guo <gary@garyguo.net>,
 =?UTF-8?Q?Bj=C3=B6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>,
 Benno Lossin <benno.lossin@proton.me>,
 Andreas Hindborg <a.hindborg@samsung.com>, Kees Cook
 <keescook@chromium.org>, Al Viro <viro@zeniv.linux.org.uk>,
 Andrew Morton <akpm@linux-foundation.org>
References: <20240208-alice-mm-v2-0-d821250204a6@google.com>
 <20240208-alice-mm-v2-1-d821250204a6@google.com>
From: =?UTF-8?Q?Carlos_L=C3=B3pez?= <clopez@suse.de>
In-Reply-To: <20240208-alice-mm-v2-1-d821250204a6@google.com>
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On 8/2/24 16:47, Alice Ryhl wrote:
> +    /// Create a reader that can access the same range of data.
> +    ///
> +    /// Reading from the clone does not advance the current reader.
> +    ///
> +    /// The caller should take care to not introduce TOCTOU issues, as described
> +    /// in the documentation for [`UserSlice`].
> +    pub fn clone_reader(&self) -> UserSliceReader {
> +        UserSliceReader {
> +            ptr: self.ptr,
> +            length: self.length,
> +        }
> +    }

Just out of curiosity, is there any reason why this is not implemented
in terms of the Clone trait?

-- 
Carlos López
Security Engineer
SUSE Software Solutions