linux-kernel - Re: [PATCH v2 1/6] rust: module: add static pointer to `{init,cleanup}

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240724204649.7de3ffed.gary@garyguo.net>
Date: Wed, 24 Jul 2024 20:46:49 +0100
From: Gary Guo <gary@...yguo.net>
To: Miguel Ojeda <ojeda@...nel.org>
Cc: Josh Poimboeuf <jpoimboe@...nel.org>, Peter Zijlstra
 <peterz@...radead.org>, Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar
 <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>, Dave Hansen
 <dave.hansen@...ux.intel.com>, Masahiro Yamada <masahiroy@...nel.org>,
 x86@...nel.org, "H. Peter Anvin" <hpa@...or.com>, Nathan Chancellor
 <nathan@...nel.org>, Nicolas Schier <nicolas@...sle.eu>, Wedson Almeida
 Filho <wedsonaf@...il.com>, Alex Gaynor <alex.gaynor@...il.com>, Boqun Feng
 <boqun.feng@...il.com>, Björn Roy Baron
 <bjorn3_gh@...tonmail.com>, Benno Lossin <benno.lossin@...ton.me>, Andreas
 Hindborg <a.hindborg@...sung.com>, Alice Ryhl <aliceryhl@...gle.com>,
 rust-for-linux@...r.kernel.org, linux-kernel@...r.kernel.org,
 patches@...ts.linux.dev
Subject: Re: [PATCH v2 1/6] rust: module: add static pointer to
 `{init,cleanup}_module()`

On Wed, 24 Jul 2024 18:14:54 +0200
Miguel Ojeda <ojeda@...nel.org> wrote:

> Add the equivalent of the `___ADDRESSABLE()` annotation in the
> `module_{init,exit}` macros to the Rust `module!` macro.
> 
> Without this, `objtool` would complain if enabled for Rust, e.g.:
> 
>     samples/rust/rust_print.o: warning: objtool: cleanup_module(): not an indirect call target
>     samples/rust/rust_print.o: warning: objtool: init_module(): not an indirect call target
> 
> Signed-off-by: Miguel Ojeda <ojeda@...nel.org>
> ---
>  rust/macros/module.rs | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/rust/macros/module.rs b/rust/macros/module.rs
> index 411dc103d82e..571ffa2e189c 100644
> --- a/rust/macros/module.rs
> +++ b/rust/macros/module.rs
> @@ -256,6 +256,12 @@ mod __module_init {{
>                          unsafe {{ __init() }}
>                      }}
>  
> +                    #[cfg(MODULE)]
> +                    #[doc(hidden)]
> +                    #[used]
> +                    #[link_section = \".init.data\"]

Should this be in section `.discard.addressable` instead?

> +                    static __UNIQUE_ID___addressable_init_module: unsafe extern \"C\" fn() -> i32 = init_module;
> +
>                      #[cfg(MODULE)]
>                      #[doc(hidden)]
>                      #[no_mangle]
> @@ -269,6 +275,12 @@ mod __module_init {{
>                          unsafe {{ __exit() }}
>                      }}
>  
> +                    #[cfg(MODULE)]
> +                    #[doc(hidden)]
> +                    #[used]
> +                    #[link_section = \".exit.data\"]
> +                    static __UNIQUE_ID___addressable_cleanup_module: extern \"C\" fn() = cleanup_module;
> +
>                      // Built-in modules are initialized through an initcall pointer
>                      // and the identifiers need to be unique.
>                      #[cfg(not(MODULE))]