Skip to content

Catch panics/unwinding in destruction of TLS values #105426

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Dec 30, 2022
Merged
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
21 changes: 14 additions & 7 deletions library/std/src/thread/local.rs
Original file line number Diff line number Diff line change
Expand Up @@ -905,9 +905,8 @@ pub mod statik {
pub mod fast {
use super::lazy::LazyKeyInner;
use crate::cell::Cell;
use crate::fmt;
use crate::mem;
use crate::sys::thread_local_dtor::register_dtor;
use crate::{fmt, mem, panic};

#[derive(Copy, Clone)]
enum DtorState {
Expand Down Expand Up @@ -1028,10 +1027,15 @@ pub mod fast {
// `Option<T>` to `None`, and `dtor_state` to `RunningOrHasRun`. This
// causes future calls to `get` to run `try_initialize_drop` again,
// which will now fail, and return `None`.
unsafe {
//
// Wrap the call in a catch to ensure unwinding is caught in the event
// a panic takes place in a destructor.
if let Err(_) = panic::catch_unwind(panic::AssertUnwindSafe(|| unsafe {
let value = (*ptr).inner.take();
(*ptr).dtor_state.set(DtorState::RunningOrHasRun);
drop(value);
})) {
rtabort!("thread local panicked on drop");
}
}
}
Expand All @@ -1044,10 +1048,8 @@ pub mod fast {
pub mod os {
use super::lazy::LazyKeyInner;
use crate::cell::Cell;
use crate::fmt;
use crate::marker;
use crate::ptr;
use crate::sys_common::thread_local_key::StaticKey as OsStaticKey;
use crate::{fmt, marker, panic, ptr};

/// Use a regular global static to store this key; the state provided will then be
/// thread-local.
Expand Down Expand Up @@ -1137,12 +1139,17 @@ pub mod os {
//
// Note that to prevent an infinite loop we reset it back to null right
// before we return from the destructor ourselves.
unsafe {
//
// Wrap the call in a catch to ensure unwinding is caught in the event
// a panic takes place in a destructor.
if let Err(_) = panic::catch_unwind(|| unsafe {
let ptr = Box::from_raw(ptr as *mut Value<T>);
let key = ptr.key;
key.os.set(ptr::invalid_mut(1));
drop(ptr);
key.os.set(ptr::null_mut());
}) {
rtabort!("thread local panicked on drop");
}
}
}