Files

T

osobhandClaude Opus 5.5 d493d4792e fix: apply the superblock extension and cache image in every opener

File, MmapFile and LazyFile decoded the superblock extension and laid a
metadata cache image over the file's metadata; the other readers did
not, so the same file read differently by entry point: NativeVol,
AsyncHDF5File and MpiVol (clawhdf5-io) and the external source files of
a virtual dataset (clawhdf5-format vds.rs) read a file with an image
from its own bytes, which libhdf5 does not (they may be stale, or zeros:
h5clear_mdc_image.h5 failed with InvalidObjectHeaderVersion(0)), and
skipped the extension checks File::open makes (cve-2020-10810/10812).

Each of them owns its buffer, so each now calls the shared
superblock_ext::apply_cache_image_in_place, which checks the extension
and writes the image's entries in place (only the image block is
copied). These readers read whole datasets and cannot open a file and
fail each object, so an image libhdf5 cannot load is refused with the
image's error, never read around. clawhdf5-io's vol::load_hdf5 wraps it
for NativeVol (at open; for from_bytes the error is reported on read,
as a truncated file already was) and MpiVol. The MpiVol edit is minimal
and was not compiled: the mpi-io feature needs an MPI installation this
machine does not have (mpi-sys's build script panics).

Tests: NativeVol (open_path and from_bytes), AsyncHDF5File and a VDS
whose source file is h5clear_mdc_image.h5 (vds_interop.rs, against
h5py) read the fixture's values; the corrupted-image variants are
refused. Each fails without its fix.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

2026-09-26 11:49:13 -05:00

src

fix: apply the superblock extension and cache image in every opener

2026-09-26 11:49:13 -05:00

Cargo.toml

build: declare Rust 1.92 as the MSRV and check it in CI

2026-09-23 11:05:26 -05:00

README.md

docs: fix stale package names, counts, and CLI subcommands

2026-06-03 11:17:04 +00:00

README.md

clawhdf5-io

I/O abstraction layer for clawhdf5.

Features

Memory-mapped file access (mmap feature)
Async I/O via Tokio (async feature)
HSDS remote access (hsds feature)
Prefetching and sweep optimizations

Usage

use clawhdf5_io::MmapReader;

let reader = MmapReader::open("data.h5").unwrap();

License

MIT