rust: export generated symbols

All symbols are reexported reusing the `EXPORT_SYMBOL_GPL` macro
from C. The lists of symbols are generated on the fly.

There are three main sets of symbols to distinguish:

  - The ones from the `core` and `alloc` crates (from the Rust
    standard library). The code is licensed as Apache/MIT.

  - The ones from our abstractions in the `kernel` crate.

  - The helpers (already exported since they are not generated).

We export everything as GPL. This ensures we do not mistakenly
expose GPL kernel symbols/features as non-GPL, even indirectly.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com>
Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com>
Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
Co-developed-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Signed-off-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This commit is contained in:
Miguel Ojeda 2021-07-03 17:18:23 +02:00
parent 247b365dc8
commit 8fcbf02492

21
rust/exports.c Normal file
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// SPDX-License-Identifier: GPL-2.0
/*
* A hack to export Rust symbols for loadable modules without having to redo
* the entire `include/linux/export.h` logic in Rust.
*
* This requires the Rust's new/future `v0` mangling scheme because the default
* one ("legacy") uses invalid characters for C identifiers (thus we cannot use
* the `EXPORT_SYMBOL_*` macros).
*
* All symbols are exported as GPL-only to guarantee no GPL-only feature is
* accidentally exposed.
*/
#include <linux/module.h>
#define EXPORT_SYMBOL_RUST_GPL(sym) extern int sym; EXPORT_SYMBOL_GPL(sym)
#include "exports_core_generated.h"
#include "exports_alloc_generated.h"
#include "exports_bindings_generated.h"
#include "exports_kernel_generated.h"