fix(streaming): reject oversized ZSTD frames instead of fatal() - #22830
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stelfrag merged 3 commits intoJun 29, 2026
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…ful failure handling Handle oversized ZSTD frames gracefully by logging an error and failing the connection instead of crashing.
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No issues found across 2 files
Confidence score: 5/5
- Automated review surfaced no issues in the provided summaries.
- No files require special attention.
Architecture diagram
sequenceDiagram
participant Peer as Remote Peer (compressed data)
participant Decomp as stream_decompress_zstd()
participant Buffer as Output Buffer (COMPRESSION_MAX_CHUNK)
participant Logger as netdata_log_error
participant Conn as Stream Connection Manager
participant Test as unittest_stream_decompress_bomb_zstd()
participant ZSTD_Comp as ZSTD_compress()
Note over Peer,Conn: Production Flow — ZSTD Frame Handling
Peer->>Decomp: compressed data (may be bomb)
Decomp->>Buffer: decompress into fixed-size buffer
alt InBuffer still has leftover bytes after buffer full
Decomp->>Decomp: detect oversized frame
Note over Decomp,Logger: NEW: graceful handling instead of fatal()
Decomp->>Logger: netdata_log_error("…failing the connection")
Decomp-->>Conn: return 0 (error)
Conn->>Conn: tear down connection / fail stream
else No leftover (normal frame)
Decomp-->>Conn: decompressed_size
Conn->>Conn: continue streaming
end
Note over Test,Conn: Regression Test (unittest_stream_decompress_bomb_zstd())
Test->>ZSTD_Comp: compress 2MB zeros -> bomb frame
ZSTD_Comp-->>Test: compressed bomb (small)
Test->>Decomp: stream_decompress(bomb)
Decomp->>Buffer: decompress, buffer fills, data left
Decomp->>Logger: netdata_log_error (graceful)
Decomp-->>Test: return 0
Test->>Test: assert return == 0 (no crash)
Test->>ZSTD_Comp: compress "the quick brown fox..." -> normal frame
ZSTD_Comp-->>Test: compressed normal
Test->>Decomp: stream_decompress(normal)
Decomp->>Buffer: decompress, fully consumed
Decomp-->>Test: return original length
Test->>Test: assert data matches original
stelfrag
marked this pull request as ready for review
June 23, 2026 07:13
thiagoftsm
approved these changes
Jun 23, 2026
thiagoftsm
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Replication and streaming are working as expected. LGTM!
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stelfrag
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Jul 12, 2026
…ata#22830) * Add regression test for ZSTD decompression-bomb guard to verify graceful failure handling Handle oversized ZSTD frames gracefully by logging an error and failing the connection instead of crashing. * Fix comment to use correct constant name (COMPRESSION_MAX_MSG_SIZE) in ZSTD stream handling * Handle ZSTD compression errors by logging and returning failure gracefully
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Ferroin
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Jul 15, 2026
* Add regression test for ZSTD decompression-bomb guard to verify graceful failure handling Handle oversized ZSTD frames gracefully by logging an error and failing the connection instead of crashing. * Fix comment to use correct constant name (COMPRESSION_MAX_MSG_SIZE) in ZSTD stream handling * Handle ZSTD compression errors by logging and returning failure gracefully
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Summary
Summary by cubic
Reject oversized ZSTD frames by logging and cleanly failing the stream instead of fatal()-ing the agent. Adds a regression test and improves ZSTD error handling.
stream_decompress_zstd, if compressed bytes remain after filling the output buffer, log withnetdata_log_errorand return 0 to drop the connection.unittest_stream_decompress_bomb_zstd()and wire it intounittest_stream_compressions()(behindENABLE_ZSTD) to verify rejection and a normal-frame round trip; fix comment to referenceCOMPRESSION_MAX_MSG_SIZE.Written for commit 25154f8. Summary will update on new commits.