linux-kernel - [PATCH v5 2/5] rust: str: implement `Index` for `BStr`

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: <20250204-module-params-v3-v5-2-bf5ec2041625@kernel.org>
Date: Tue, 04 Feb 2025 13:02:09 +0100
From: Andreas Hindborg <a.hindborg@...nel.org>
To: 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>, 
 Benno Lossin <benno.lossin@...ton.me>, Alice Ryhl <aliceryhl@...gle.com>, 
 Masahiro Yamada <masahiroy@...nel.org>, 
 Nathan Chancellor <nathan@...nel.org>, Nicolas Schier <nicolas@...sle.eu>, 
 Luis Chamberlain <mcgrof@...nel.org>
Cc: Trevor Gross <tmgross@...ch.edu>, 
 Adam Bratschi-Kaye <ark.email@...il.com>, rust-for-linux@...r.kernel.org, 
 linux-kernel@...r.kernel.org, linux-kbuild@...r.kernel.org, 
 Petr Pavlu <petr.pavlu@...e.com>, Sami Tolvanen <samitolvanen@...gle.com>, 
 Daniel Gomez <da.gomez@...sung.com>, Simona Vetter <simona.vetter@...ll.ch>, 
 Greg KH <gregkh@...uxfoundation.org>, linux-modules@...r.kernel.org, 
 Andreas Hindborg <a.hindborg@...nel.org>
Subject: [PATCH v5 2/5] rust: str: implement `Index` for `BStr`

The `Index` implementation on `BStr` was lost when we switched `BStr` from
a type alias of `[u8]` to a newtype. This patch adds back `Index` by
implementing `Index` for `BStr` when `Index` would be implemented for
`[u8]`.

Signed-off-by: Andreas Hindborg <a.hindborg@...nel.org>
---
 rust/kernel/str.rs | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
index 002dcddf7c7687522a0acbff3ce6f65fa890e216..1eb945bed77d6592216cf30678fcca70d4c0b3b3 100644
--- a/rust/kernel/str.rs
+++ b/rust/kernel/str.rs
@@ -114,6 +114,17 @@ fn eq(&self, other: &Self) -> bool {
     }
 }
 
+impl<Idx> Index<Idx> for BStr
+where
+    Idx: core::slice::SliceIndex<[u8], Output = [u8]>,
+{
+    type Output = Self;
+
+    fn index(&self, index: Idx) -> &Self::Output {
+        BStr::from_bytes(&self.0[index])
+    }
+}
+
 /// Creates a new [`BStr`] from a string literal.
 ///
 /// `b_str!` converts the supplied string literal to byte string, so non-ASCII

-- 
2.47.0