fix: types: error out on decoding BlockMsg with extraneous data #10863
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fix: types: error out on decoding BlockMsg with extraneous data Fixes OSS-fuzz issue 48208: lotus:fuzz_block_msg Signed-off-by: Yolan Romailler <anomalroil@users.noreply.github.com>
fridrik01
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May 15, 2023
ZenGround0
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May 22, 2023
Signed-off-by: Yolan Romailler <AnomalRoil@users.noreply.github.com>
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arajasek
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This fixes the OSS-fuzz finding 48208: lotus:fuzz_block_msg.
The error being that invalid CBOR encoding of BlockMsg can lead to decoded values that do not re-serialize as is. Not necessarily a security issue, but making sure we're not decoding invalid representations shouldn't hurt and prevents us from having to worry about having multiple CBOR representation of the same thing (our CBOR decoder requires canonical CBOR).
Related Issues
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=48208
Proposed Changes
This reads the remaining bytes in the reader provided to
UnmarshalCBORand if it still contains data, errors out.Additional Info
The oss-fuzz testcase boils down to:
0x83F6808020which contains an extra byte after the data items: https://cbor.me/?bytes=83(F6-80-80((20
Checklist
Before you mark the PR ready for review, please make sure that:
<PR type>: <area>: <change being made>fix: mempool: Introduce a cache for valid signaturesPR type: fix, feat, build, chore, ci, docs, perf, refactor, revert, style, testarea, e.g. api, chain, state, market, mempool, multisig, networking, paych, proving, sealing, wallet, deps