Polygon Labs mentioned any Polygon PoS node that stayed on pre-hardfork Bor or Heimdall binaries previous two August activation heights has already fallen out of canonical consensus. In follow, the stale node should improve and catch up earlier than it will probably observe the community’s accepted historical past once more.
The corporate’s Aug. 27 safety evaluation described a client-compatibility consequence. Polygon mentioned it had not noticed mainnet disruption from Austin and framed the disclosed modifications as proactive fixes.
Bor is Polygon PoS’s execution consumer, whereas Heimdall handles consensus and checkpointing. Bor variations sooner than v2.10.0 are incompatible after Austin activated at mainnet block 91,949,700, a cutoff that applies to all Bor node roles.
Heimdall validators and full nodes want v0.11.0 after Kyoto activated at top 51,533,000. Polygon’s Heimdall launch discover dates that mainnet activation to Aug. 18 at 10:10:31 UTC.
Austin and Kyoto addressed separate consumer dangers
Austin capped the fuel consumed whereas Bor processes state-sync occasions from L1-to-L2 bridge deposits. These occasions execute contract code and precompiles, however their fuel use was not beforehand counted in opposition to a set block-level ceiling.
Sufficient occasions, or one sufficiently pricey occasion, might make block processing gradual sufficient to stall the chain transiently.
The second weak point sat in Bor’s TxDependency extra-data discipline, a touch used for parallel execution. As a result of the producer-supplied discipline had no measurement restrict, a block producer might place an arbitrarily massive blob in an in any other case legitimate sibling block and crash friends that attempted to course of it.
Austin eliminated the sphere from the wire format, and Polygon categorized each weaknesses as resource-exhaustion dangers.
The general public Bor v2.10.0 launch data Austin’s mainnet and Amoy activation blocks. GitHub confirmed v2.10.1 as the newest Bor launch when checked Aug. 28, whereas v2.10.0 or later offers Austin compatibility.
Operationally, one Austin path threatened delayed block processing, whereas the opposite might terminate friends receiving a producer’s outsized information discipline.
Kyoto’s highest-severity repair targets deeply nested google.protobuf.Any messages. A sender might cheaply assemble one transaction that pressured each validator to spend closely on decoding. The hardfork added a byte-level nesting examine at each mempool admission and block-proposal processing, retaining these paths constant.
It individually capped fee-coin lists earlier than an O(n) validation scan, and Heimdall’s integration permits one price coin.
Different Kyoto modifications deal with distinct edge instances. They normalize checkpoint signature restoration bytes so a sound signature can not fail restoration on Ethereum and stall anchoring, make repeated producer-downtime messages idempotent, bind milestone-range votes to the signed dad or mum hash, and stop a failed future-span creation from blocking milestone dedication.
Replay keys for topup, clerk, and stake occasions have been additionally made injective for out-of-range log indexes so distinct layer-1 occasions can not silently shadow one another.
Each hardforks are plain binary upgrades with no state migration or genesis change, and nodes that had not diverged require no resync.
Operators already previous the related top on an older consumer ought to set up the relevant launch, roll again to a pre-hardfork level if wanted, and resync below Polygon’s steerage.
