Fix unsound require assumptions in Liveness spec (#781)#784
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Fix unsound require assumptions in Liveness spec (#781)#784claude[bot] wants to merge 13 commits into
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In summarySafeTransferFrom, the ghost balance under/overflow was silenced with require_uint256, which is unsound in liveness rules (@withrevert + assert !lastReverted): it assumes away the very no-revert precondition the rules aim to prove. Switch both branches to assert_uint256, turning the hidden assumption into a proof obligation, and add the explicit, justified assumptions each rule now needs (singleton solvency for out-transfers, bounded supply for in-transfers). Fixes #781 Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_013Kx6WMx5o6emArfUMRXERr
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_013Kx6WMx5o6emArfUMRXERr
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_013Kx6WMx5o6emArfUMRXERr
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_013Kx6WMx5o6emArfUMRXERr
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… require, drop redundant per-rule bounds
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Signed-off-by: MathisGD <74971347+MathisGD@users.noreply.github.com>
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Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_013Kx6WMx5o6emArfUMRXERr
…liveness-assert-soundness
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_013Kx6WMx5o6emArfUMRXERr
…r-amount bound holds Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_013Kx6WMx5o6emArfUMRXERr
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Requested by Mathis GD · Slack thread
Fixes #781.
Before: the transfer summary in
certora/specs/Liveness.specusedrequire_uint256to update the ghostbalance, silently assuming no under/overflow — unsound in the liveness rules, which assert!lastRevertedand so must not assume away the very no-revert precondition.After: the summary uses
assert_uint256, making no-under/overflow a proof obligation. Thebalanceghost (a mathint) is bounded two-sided (0 <= balance[token] < 2^128) in the summary as a structural fact, and each rule that sends tokens out carries an explicit lower bound (balance >= totalSupplyAssets(id)/>= assets/>= collateral) as the "singleton holds enough tokens" liveness assumption. Rules that lacked it also assume Morpho is not the caller (currentContract != e.msg.sender).