fix(l1): fix exponential overflow in fake exponential #5093
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MegaRedHand
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Oct 29, 2025
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| #[test] | ||
| fn test_fake_exponential_overflow() { | ||
| // With u64 this overflows | ||
| fake_exponential(57532635, 3145728, 3338477); | ||
| } |
Collaborator
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Let's add a test with the maximum expected inputs here, for good measure:
fake_exponential(MIN_BASE_FEE_PER_BLOB_GAS, u64::MAX, BLOB_BASE_FEE_UPDATE_FRACTION);
MegaRedHand
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Oct 29, 2025
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MegaRedHand
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MegaRedHand
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I'm pretty sure the u64::MAX isn't reachable in practice, and can be bounded further down. We should check this, but I think it's safe to merge this PR as-is.
| } | ||
| output / denominator | ||
| if (output / denominator) > U256::from(u64::MAX) { | ||
| u64::MAX |
Collaborator
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We should panic here, since I'm sure this is unreachable. In a later PR we can update this with an explanation.
Comment on lines
+987
to
+991
| #[test] | ||
| fn test_fake_exponential_overflow() { | ||
| // With u64 this overflows | ||
| fake_exponential(57532635, 3145728, 3338477); | ||
| } |
jrchatruc
approved these changes
Oct 29, 2025
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Motivation
Fake Exponential defined in
block.rscan overflow. As such, we need to use the U256 data type to avoid overflowsDescription