4 Commits

Include renames

Author	SHA1	Message	Date
Chris Lu	1e858d8af0	fix(ec): make ec.decode write-path crash-safe and atomic (#9949) ... * fix(ec): check decode .idx writes and fsync decoded .dat/.idx WriteIdxFileFromEcIndex silently dropped io.Copy and Write errors, so a short or failed write of the reconstructed .idx went unnoticed and the caller proceeded to delete the source EC shards. Propagate those errors. Also fsync the decoded .dat and .idx before returning, so the bytes are durable before the shards that produced them are removed cluster-wide. Mirror the .idx fsync into the Rust volume server (its .dat already syncs and its writes already propagate errors). * fix(ec): publish decoded .dat/.idx atomically via temp file and rename WriteDatFile and WriteIdxFileFromEcIndex wrote in place at the final name with O_TRUNC. A crash mid-write left a truncated .dat/.idx at the final name beside the still-present EC shards; on restart that partial file could be mounted as the live volume even though the shards held the real data. Write to a .tmp file, fsync it, then rename into place and fsync the directory, so the final name is only ever absent or complete. A failed decode removes its own temp file rather than leaking it. Add util.FsyncDir as the shared directory-fsync primitive and reuse the Rust volume server's fsync_dir for the mirrored change. * fix(ec): propagate .ecj read errors in the Rust decoder Path::exists returned false for any error (permission denied, transient IO), silently skipping the deletion journal and resurrecting deleted needles as live. Read the journal directly and treat only NotFound as absent, propagating other errors. The Go decoder already behaves this way (FileExists returns false only for IsNotExist, then the open surfaces other errors). * fix(ec): remove rename destination on Windows in the Rust decoder publish std::fs::rename does not replace an existing file on every Windows version. Remove the destination first under a Windows guard before the atomic publish rename, matching the compaction commit path.	2026-06-13 21:26:07 -07:00
Chris Lu	9658f309d2	EC bitrot detection: per-shard checksum sidecars (#9761) ... * ec: add EC bitrot checksum protobuf EcBitrotProtection/EcShardChecksums/ChecksumAlgorithm sidecar messages, copy_ecsum_file and unsafe_ignore_sidecar fields, and a CHECKSUM scrub mode. * ec: bitrot checksum sidecar format, validation, and per-volume load Per-shard CRC32C block checksums in an optional <base>.ecsum sidecar with a self-integrity header; validation, rolling builder, backfill primitive, and EcVolume load on mount + removal on destroy. * ec: capture per-shard checksums at encode; verify-and-exclude on rebuild WriteEcFilesWithContext returns the protection computed inline during encoding. generateMissingEcFiles verifies present inputs against the sidecar, excludes corrupt ones, regenerates in place, and re-verifies; fail-closed unless unsafe_ignore_sidecar, removing all generated outputs on failure. * ec: read-only checksum scrub with Reed-Solomon arbiter ChecksumScrub verifies each local shard against the sidecar and reconstructs flagged shards from the clean shards so stale-sidecar false positives are not reported. Wired to the gRPC CHECKSUM mode and ec.scrub -mode checksum. * ec: server-side bitrot sidecar write, copy, cleanup, and opportunistic backfill Write .ecsum at fresh encode; propagate it with copy_ecsum_file (tolerant); remove it on full delete and decode; rebuild honors unsafe_ignore_sidecar and opportunistically backfills a sidecar when all shards are reachable. * ec: volume server bitrot config flags -ec.bitrotChecksum (default on) and -ec.bitrotBlockSizeMB (default 16). * fix(ec_bitrot): bound -ec.bitrotBlockSizeMB before the int64 multiply Validate the MiB value is in [1, 1024] before multiplying by 1 MiB, so a huge flag value cannot overflow int64 and slip past the power-of-two check, and a block size cannot collapse a sidecar to a few oversized blocks. * fix(ec_bitrot): distribute the .ecsum sidecar from the worker encode path The worker EC encode wrote the generation-0 sidecar locally but never added it to shardFiles, so DistributeEcShards never shipped it and the distributed holders came up unprotected. Append it to shardFiles and map the ecsum shard type to its extension in the sender so it travels with the shards. * fix(ec_bitrot): remove orphaned sidecars when the generation is gone Gate sidecar removal on existingShardCount==0 alone rather than also requiring a stray .ecx. A sidecar whose shards have all been deleted is orphaned and must be removed even when no .ecx remains, or it leaks. .ecx/.ecj/.vif removal stays gated on hasEcxFile as before. * fix(ec_bitrot): do not fold checksum blocks scanned into TotalFiles ChecksumScrub's first return is blocks scanned, not files. Discard it so the scrub response's TotalFiles (a needle/file count) is not inflated by the block count for CHECKSUM mode. * test(ec_bitrot): clean up generated .ecsum sidecars in removeGeneratedFiles * fix(ec_bitrot): reject an oversized sidecar payload before the uint32 cast The header stores payload_len as a uint32; bound the payload before the conversion so a pathological manifest cannot truncate the length field and corrupt the sidecar. A real manifest is a few KB, so this never trips. * fix(ec_bitrot): cap -ec.bitrotBlockSizeMB at 64 MiB The block size becomes the per-shard scratch buffer the scrub/backfill path allocates, so an over-large value (e.g. 1 GiB) is a memory hazard per concurrent scrub worker. Lower the upper bound from 1024 to 64 MiB. * fix(ec_bitrot): add -ecUnsafeIgnoreSidecar to weed tool fix -ecx The -ecx recovery path reconstructs missing shards via RebuildEcFilesWithContext, which fails closed on a malformed/stale .ecsum. Without an override flag an operator could not complete the rebuild without manually deleting the sidecar. Expose -ecUnsafeIgnoreSidecar (default false) and thread it through. * fix(ec_bitrot): bound sidecar payload with a direct int constant; drop readFull Guard len(payload) against a plain int constant (1 GiB) before the allocation instead of a uint64 MaxUint32 compare, so the allocation-size value is provably bounded (clears the CodeQL overflow alert) and the math import is no longer needed. Inline os.File.ReadAt with io.EOF handling in verifyShardFileBlocks and remove the now-redundant readFull helper (os.File.ReadAt fills the slice or errors). * test(ec_bitrot): use slices.Contains instead of a hand-rolled containsU32 * refactor(ec): fold the EcFiles WithContext variants into the base functions RebuildEcFiles now takes the *ECContext directly (nil => derive from .vif as before) and WriteEcFiles takes it too (nil => default), removing the parallel RebuildEcFilesWithContext / WriteEcFilesWithContext names. Callers that had an explicit context drop the WithContext suffix; the default-context callers pass nil. No behavior change. * refactor(ec): pass BackgroundECContext instead of nil to Write/RebuildEcFiles Add a non-nil BackgroundECContext placeholder (analogous to context.Background()) and have callers with no specific layout pass it instead of a nil *ECContext. WriteEcFiles resolves a zero/background context to the default ratio and RebuildEcFiles resolves it from the .vif, so behavior is unchanged. * fix(ec_bitrot): make BackgroundECContext a func; RebuildEcFiles fails closed on bad .vif - BackgroundECContext is now a function returning a fresh *ECContext, so callers cannot mutate a shared singleton or race on it (and it mirrors context.Background, which is also a function). - RebuildEcFiles now propagates the MaybeLoadVolumeInfo error: a present-but- unreadable .vif fails closed instead of silently rebuilding with the default ratio (which would corrupt a custom-ratio volume). Pass an explicit ctx to override.	2026-05-31 18:52:44 -07:00
Chris Lu	e648c76bcf	go fmt	2026-04-10 17:31:14 -07:00
Chris Lu	d4548376a1	fix(ec): off-by-one in nLargeBlockRows causes EC read corruption (#8957) ... * fix(ec): off-by-one in nLargeBlockRows causes EC read corruption (#8947) The nLargeBlockRows formula in locateOffset used (shardDatSize-1)/largeBlockLength, which produces an off-by-one error when shardDatSize is an exact multiple of largeBlockLength (e.g. a 30GB volume with 10 data shards = 3GB per shard). This causes needles in the last large block row to be mislocated as small blocks, reading from completely wrong shard positions and returning garbage data. Fix: remove the -1 from locateOffset and only apply it in the ecdFileSize fallback path (old volumes without datFileSize in .vif), where it's needed to handle the ambiguous case conservatively. Also fix ReadEcShardNeedle to pass offset=0 to ReadBytes, consistent with the scrub path, since the bytes buffer already starts at position 0. * fix: add volume context to EC read errors, remove contextless glog The glog.Errorf in ReadBytes logged "entry not found" without any volume ID, making it impossible to identify which volume was affected. Remove this contextless log and instead add volume ID, needle ID, offset, and size to the error returned from the EC read path. The EC scrub callers already wrap errors with volume context.	2026-04-07 12:02:51 -07:00