Reject channels if the total reserves are larger than the funding #1454
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TheBlueMatt
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vincenzopalazzo
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jkczyz
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valentinewallace
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jkczyz
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The `full_stack_target` fuzzer managed to find a subtraction underflow in the new `Channel::get_htlc_maximum` function where we subtract both sides' reserve values from the channel funding. Such a channel is obviously completely useless, so we should reject it during opening instead of integer-underflowing later. Thanks to Chaincode Labs for providing the fuzzing resources which found this bug!
The calculation uses the reserve, so we should mention it in the error we send to our peers.
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Oops, missed a test had the same error in it, fixed that and made the fixup a Real Commit instead. |
valentinewallace
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jkczyz
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dunxen
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The
full_stack_targetfuzzer managed to find a subtractionunderflow in the new
Channel::get_htlc_maximumfunction where wesubtract both sides' reserve values from the channel funding. Such
a channel is obviously completely useless, so we should reject it
during opening instead of integer-underflowing later.
Thanks to Chaincode Labs for providing the fuzzing resources which
found this bug!