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Change API to be the same as Honggfuzz-rs and eventually AFL.rs #33

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Change API to be the same as Honggfuzz-rs and eventually AFL.rs #33

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e6a1875
Change API to be the same as Honggfuzz-rs and eventually AFL.rs
PaulGrandperrin Apr 28, 2018
9c6fcf3
Use more unsafe code to remove the 'static bound on the user's closure
PaulGrandperrin Apr 28, 2018
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14 changes: 7 additions & 7 deletions src/lib.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -7,7 +7,7 @@ extern "C" {
fn _ZN6fuzzer12FuzzerDriverEPiPPPcPFiPKhmE(argc: *mut c_int, argv: *mut *mut *mut c_char, callback: extern fn(*const u8, usize) -> c_int );
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Is this the same on all platforms? Should we be exposing an extern c function instead?

}

static mut STATIC_CLOSURE: Option<Box<FnMut(&[u8])>> = None;
static mut STATIC_CLOSURE: Option<&mut FnMut(&[u8])> = None;
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This isn't safe at all. We should not be using FnMut.


// #[no_mangle]
// pub extern "C" fn LLVMFuzzerInitialize(_argc: *const isize, _argv: *const *const *const u8) -> isize {
Expand Down Expand Up @@ -37,7 +37,7 @@ pub extern "C" fn LLVMFuzzerTestOneInput(data: *const u8, size: usize) -> c_int
0
}

pub fn fuzz<F>(closure: F) where F: Fn(&[u8]) + std::panic::RefUnwindSafe + 'static {
pub fn fuzz<F>(closure: &mut F) where F: FnMut(&[u8]) + std::panic::RefUnwindSafe {
// Converts env::args() to C format
let args = std::env::args()
.map(|arg| CString::new(arg).unwrap()) // convert args to null terminated C strings
Expand All @@ -63,8 +63,8 @@ pub fn fuzz<F>(closure: F) where F: Fn(&[u8]) + std::panic::RefUnwindSafe + 'sta
}));

unsafe {
// save closure at static location
STATIC_CLOSURE = Some(Box::new(closure));
// save closure at static location and forget its lifetime
STATIC_CLOSURE = Some(std::mem::transmute(closure as &mut FnMut(&[u8])));
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This is unnecessary, it can be done statically by wrapping it with a function


// call C++ mangled method `fuzzer::FuzzerDriver()`
_ZN6fuzzer12FuzzerDriverEPiPPPcPFiPKhmE(&mut argc, &mut argv, LLVMFuzzerTestOneInput);
Expand All @@ -74,13 +74,13 @@ pub fn fuzz<F>(closure: F) where F: Fn(&[u8]) + std::panic::RefUnwindSafe + 'sta
#[macro_export]
macro_rules! fuzz {
(|$buf:ident| $body:block) => {
libfuzzer_sys::fuzz(move |$buf| $body);
libfuzzer_sys::fuzz(&mut |$buf| $body);
};
(|$buf:ident: &[u8]| $body:block) => {
libfuzzer_sys::fuzz(move |$buf| $body);
libfuzzer_sys::fuzz(&mut |$buf| $body);
};
(|$buf:ident: $dty: ty| $body:block) => {
libfuzzer_sys::fuzz(move |$buf| {
libfuzzer_sys::fuzz(&mut |$buf| {
let $buf: $dty = {
use arbitrary::{Arbitrary, RingBuffer};
if let Ok(d) = RingBuffer::new($buf, $buf.len()).and_then(|mut b|{
Expand Down