From 41cc07a099200f85f1f1acfebf40b7139ad85745 Mon Sep 17 00:00:00 2001 From: Artyom Pavlov Date: Tue, 14 Mar 2023 04:14:47 +0000 Subject: [PATCH] Switch the custom backend to Rust ABI (#347) Closes #345 This change makes the code safe against potential panics in custom functions. --- src/custom.rs | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/src/custom.rs b/src/custom.rs index 76445ccf..c9207d06 100644 --- a/src/custom.rs +++ b/src/custom.rs @@ -78,9 +78,9 @@ macro_rules! register_custom_getrandom { ($path:path) => { // TODO(MSRV 1.37): change to unnamed block const __getrandom_internal: () = { - // We use an extern "C" function to get the guarantees of a stable ABI. + // We use Rust ABI to be safe against potential panics in the passed function. #[no_mangle] - unsafe extern "C" fn __getrandom_custom(dest: *mut u8, len: usize) -> u32 { + unsafe fn __getrandom_custom(dest: *mut u8, len: usize) -> u32 { // Make sure the passed function has the type of getrandom::getrandom type F = fn(&mut [u8]) -> ::core::result::Result<(), $crate::Error>; let _: F = $crate::getrandom; @@ -97,7 +97,7 @@ macro_rules! register_custom_getrandom { #[allow(dead_code)] pub fn getrandom_inner(dest: &mut [MaybeUninit]) -> Result<(), Error> { - extern "C" { + extern "Rust" { fn __getrandom_custom(dest: *mut u8, len: usize) -> u32; } // Previously we always passed a valid, initialized slice to