Very small memory leaks reported by LeakSanitizer when testing multiple files

[qarmin]

Oxlint - 02f9903211bd8b8ea745704cd651c8f7616255c1

I got several small memory leaks, when executing command

oxlint -D all -D nursery --import-plugin --jsdoc-plugin --jest-plugin --vitest-plugin --jsx-a11y-plugin --nextjs-plugin --react-perf-plugin FOLDER_TO_TEST --fix --fix-suggestions --fix-dangerously

in CI with ~1000 files at once

sadly there is no reproduction project yet, because my fuzzer is not designed to catch issues that happens with more than one file - but I will try to create such project.

example of leak

Direct leak of 432 byte(s) in 3 object(s) allocated from:
    #0 0x561c330fe8df in malloc /rustc/llvm/src/llvm-project/compiler-rt/lib/asan/asan_malloc_linux.cpp:68:3
    oxc-project/oxc#1 0x561c335af66b in alloc::alloc::alloc::hda39ecc0318c2468 /home/runner/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:99:9
    oxc-project/oxc#2 0x561c335af66b in alloc::alloc::Global::alloc_impl::h7ce9227b5757320e /home/runner/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:195:73
    oxc-project/oxc#3 0x561c335af66b in _$LT$alloc..alloc..Global$u20$as$u20$core..alloc..Allocator$GT$::allocate::h06f332da5a74f263 /home/runner/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:257:9
    oxc-project/oxc#4 0x561c335af66b in alloc::alloc::exchange_malloc::h3d4642dd947c6a98 /home/runner/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/alloc.rs:352:18
    oxc-project/oxc#5 0x561c335af66b in alloc::boxed::Box$LT$T$GT$::new::ha4f8649d34c5ecd3 /home/runner/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/boxed.rs:254:9
    #6 0x561c335af66b in alloc::sync::Arc$LT$T$GT$::new::h5ae437f1cb23f5af /home/runner/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/sync.rs:391:25
    #7 0x561c335af66b in oxc_resolver::cache::Cache$LT$Fs$GT$::value::hfed8ec6548af329c /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/oxc_resolver-2.1.1/src/cache.rs:54:31
    #8 0x561c336112b2 in oxc_resolver::cache::CachedPath::add_extension::_$u7b$$u7b$closure$u7d$$u7d$::hc5c667472fe78ba9 /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/oxc_resolver-2.1.1/src/cache.rs:324:13
    oxc-project/oxc#9 0x561c336112b2 in std::thread::local::LocalKey$LT$T$GT$::try_with::h5875916aa2506532 /home/runner/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/thread/local.rs:308:12
    oxc-project/oxc#10 0x561c336112b2 in std::thread::local::LocalKey$LT$T$GT$::with::he29c4d2ab9c59644 /home/runner/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/thread/local.rs:272:9
    oxc-project/oxc#11 0x561c336112b2 in oxc_resolver::cache::CachedPath::add_extension::hccbbcbb454ecade9 /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/oxc_resolver-2.1.1/src/cache.rs:317:22
    oxc-project/oxc#12 0x561c336112b2 in oxc_resolver::ResolverGeneric$LT$Fs$GT$::load_extensions::h6c6a02b5a28a98b6 /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/oxc_resolver-2.1.1/src/lib.rs:598:36
    oxc-project/oxc#13 0x561c3360f28d in oxc_resolver::ResolverGeneric$LT$Fs$GT$::load_as_file::h5fb4cf9e1848af55 /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/oxc_resolver-2.1.1/src/lib.rs:530:29
    oxc-project/oxc#14 0x561c33619ecb in oxc_resolver::ResolverGeneric$LT$Fs$GT$::load_as_file_or_directory::h9b687bb2993d4d8b /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/oxc_resolver-2.1.1/src/lib.rs:576:33
    oxc-project/oxc#15 0x561c33612dee in oxc_resolver::ResolverGeneric$LT$Fs$GT$::require_relative::haf25cfc10cce3fb0 /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/oxc_resolver-2.1.1/src/lib.rs:401:29
    oxc-project/oxc#16 0x561c33615b5c in oxc_resolver::ResolverGeneric$LT$Fs$GT$::require_without_parse::hd636d7dd456f47db /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/oxc_resolver-2.1.1/src/lib.rs:311:17
    oxc-project/oxc#17 0x561c3361f924 in oxc_resolver::ResolverGeneric$LT$Fs$GT$::require::h9e752dc7f3f45391 /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/oxc_resolver-2.1.1/src/lib.rs:285:9
    #18 0x561c33620300 in oxc_resolver::ResolverGeneric$LT$Fs$GT$::resolve_impl::he46a85178977ed82 /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/oxc_resolver-2.1.1/src/lib.rs:248:27
    oxc-project/oxc#19 0x561c33620300 in oxc_resolver::ResolverGeneric$LT$Fs$GT$::resolve_tracing::h46d43630fa557313 /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/oxc_resolver-2.1.1/src/lib.rs:228:17
    oxc-project/oxc#20 0x561c33620300 in oxc_resolver::ResolverGeneric$LT$Fs$GT$::resolve::hb3f4ebea4be397ea /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/oxc_resolver-2.1.1/src/lib.rs:177:9
    oxc-project/oxc#21 0x561c336d7676 in oxc_linter::service::runtime::Runtime::process_source::_$u7b$$u7b$closure$u7d$$u7d$::hb5b01d1c657ec3fc /home/runner/work/Automated-Fuzzer/Automated-Fuzzer/oxc-main/crates/oxc_linter/src/service/runtime.rs:247:21

Looks that Cache from oxc-resolver can generate this leak(but this could be also a false positive)

oxc-resolver/src/cache.rs

Lines 28 to 32 in 8844add

	pub struct Cache<Fs> {
	pub(crate) fs: Fs,
	paths: DashSet<CachedPath, BuildHasherDefault<IdentityHasher>>,
	tsconfigs: DashMap<PathBuf, Arc<TsConfig>, BuildHasherDefault<FxHasher>>,
	}

full leak info:
leaks.txt

[Boshen]

TODO: setup miri.

Very probable that this comes from dashmap :-/

[Boshen]

Tried in #351

There's definitely a small leak in

oxc-resolver/src/cache.rs

Line 30 in fede8dc

pub static SCRATCH_PATH: RefCell<PathBuf> = RefCell::new(PathBuf::with_capacity(256));

But I don't know how to fix it :-/

[Boshen]

Close as not planned until I learn something new about this.