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| author | Kees Cook <kees+treewide@kernel.org> | 2026-09-02 15:31:14 -0700 |
|---|---|---|
| committer | Kees Cook <kees@kernel.org> | 2026-09-04 21:37:00 -0700 |
| commit | 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch) | |
| tree | c65086f9bdcd48c6360fb7cb4598bca084da1f32 /rust/proc-macro2/extra.rs | |
| download | linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip | |
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc()
family of allocations to kmalloc_obj() via the existing rules in
scripts/coccinelle/api/kmalloc_objs.cocci
This catches both the set of kmalloc() uses added since the first
kmalloc_obj() conversions in v7.0 and adds a large group missed in the
first pass due to Coccinelle not interacting well with the cleanup.h
scoped_...() family of macros[1]. I worked around this with spatch's
"--macro-file" argument to a file with all the scoped_...() macros mapped
to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control
flow indicator I could find.
Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc,
riscv, and s390 with no new warnings.
Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1]
Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2]
Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'rust/proc-macro2/extra.rs')
| -rw-r--r-- | rust/proc-macro2/extra.rs | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/rust/proc-macro2/extra.rs b/rust/proc-macro2/extra.rs new file mode 100644 index 000000000..55feb5ec7 --- /dev/null +++ b/rust/proc-macro2/extra.rs @@ -0,0 +1,153 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + +//! Items which do not have a correspondence to any API in the proc_macro crate, +//! but are necessary to include in proc-macro2. + +use crate::fallback; +use crate::imp; +use crate::marker::{ProcMacroAutoTraits, MARKER}; +use crate::Span; +use core::fmt::{self, Debug}; + +/// Invalidate any `proc_macro2::Span` that exist on the current thread. +/// +/// The implementation of `Span` uses thread-local data structures and this +/// function clears them. Calling any method on a `Span` on the current thread +/// created prior to the invalidation will return incorrect values or crash. +/// +/// This function is useful for programs that process more than 2<sup>32</sup> +/// bytes of Rust source code on the same thread. Just like rustc, proc-macro2 +/// uses 32-bit source locations, and these wrap around when the total source +/// code processed by the same thread exceeds 2<sup>32</sup> bytes (4 +/// gigabytes). After a wraparound, `Span` methods such as `source_text()` can +/// return wrong data. +/// +/// # Example +/// +/// As of late 2023, there is 200 GB of Rust code published on crates.io. +/// Looking at just the newest version of every crate, it is 16 GB of code. So a +/// workload that involves parsing it all would overflow a 32-bit source +/// location unless spans are being invalidated. +/// +/// ``` +/// use flate2::read::GzDecoder; +/// use std::ffi::OsStr; +/// use std::io::{BufReader, Read}; +/// use std::str::FromStr; +/// use tar::Archive; +/// +/// rayon::scope(|s| { +/// for krate in every_version_of_every_crate() { +/// s.spawn(move |_| { +/// proc_macro2::extra::invalidate_current_thread_spans(); +/// +/// let reader = BufReader::new(krate); +/// let tar = GzDecoder::new(reader); +/// let mut archive = Archive::new(tar); +/// for entry in archive.entries().unwrap() { +/// let mut entry = entry.unwrap(); +/// let path = entry.path().unwrap(); +/// if path.extension() != Some(OsStr::new("rs")) { +/// continue; +/// } +/// let mut content = String::new(); +/// entry.read_to_string(&mut content).unwrap(); +/// match proc_macro2::TokenStream::from_str(&content) { +/// Ok(tokens) => {/* ... */}, +/// Err(_) => continue, +/// } +/// } +/// }); +/// } +/// }); +/// # +/// # fn every_version_of_every_crate() -> Vec<std::fs::File> { +/// # Vec::new() +/// # } +/// ``` +/// +/// # Panics +/// +/// This function is not applicable to and will panic if called from a +/// procedural macro. +#[cfg(span_locations)] +#[cfg_attr(docsrs, doc(cfg(feature = "span-locations")))] +pub fn invalidate_current_thread_spans() { + crate::imp::invalidate_current_thread_spans(); +} + +/// An object that holds a [`Group`]'s `span_open()` and `span_close()` together +/// in a more compact representation than holding those 2 spans individually. +/// +/// [`Group`]: crate::Group +#[derive(Copy, Clone)] +pub struct DelimSpan { + inner: DelimSpanEnum, + _marker: ProcMacroAutoTraits, +} + +#[derive(Copy, Clone)] +enum DelimSpanEnum { + #[cfg(wrap_proc_macro)] + Compiler { + join: proc_macro::Span, + open: proc_macro::Span, + close: proc_macro::Span, + }, + Fallback(fallback::Span), +} + +impl DelimSpan { + pub(crate) fn new(group: &imp::Group) -> Self { + #[cfg(wrap_proc_macro)] + let inner = match group { + imp::Group::Compiler(group) => DelimSpanEnum::Compiler { + join: group.span(), + open: group.span_open(), + close: group.span_close(), + }, + imp::Group::Fallback(group) => DelimSpanEnum::Fallback(group.span()), + }; + + #[cfg(not(wrap_proc_macro))] + let inner = DelimSpanEnum::Fallback(group.span()); + + DelimSpan { + inner, + _marker: MARKER, + } + } + + /// Returns a span covering the entire delimited group. + pub fn join(&self) -> Span { + match &self.inner { + #[cfg(wrap_proc_macro)] + DelimSpanEnum::Compiler { join, .. } => Span::_new(imp::Span::Compiler(*join)), + DelimSpanEnum::Fallback(span) => Span::_new_fallback(*span), + } + } + + /// Returns a span for the opening punctuation of the group only. + pub fn open(&self) -> Span { + match &self.inner { + #[cfg(wrap_proc_macro)] + DelimSpanEnum::Compiler { open, .. } => Span::_new(imp::Span::Compiler(*open)), + DelimSpanEnum::Fallback(span) => Span::_new_fallback(span.first_byte()), + } + } + + /// Returns a span for the closing punctuation of the group only. + pub fn close(&self) -> Span { + match &self.inner { + #[cfg(wrap_proc_macro)] + DelimSpanEnum::Compiler { close, .. } => Span::_new(imp::Span::Compiler(*close)), + DelimSpanEnum::Fallback(span) => Span::_new_fallback(span.last_byte()), + } + } +} + +impl Debug for DelimSpan { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + Debug::fmt(&self.join(), f) + } +} |
