fix: prevent uint32 overflow in CertTable bounds check#186
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Flo354 wants to merge 1 commit intogoogle:mainfrom
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fix: prevent uint32 overflow in CertTable bounds check#186Flo354 wants to merge 1 commit intogoogle:mainfrom
Flo354 wants to merge 1 commit intogoogle:mainfrom
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CertTable.Unmarshal uses entry.Offset+entry.Length in a uint32 bounds check. When the sum exceeds 2^32 it wraps around, bypassing the check. The subsequent slice access panics. Replace with overflow-safe comparison that checks each component separately.
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The bounds check in
CertTable.Unmarshal(abi/abi.go:871) uses uint32 arithmetic:When
Offset + Lengthexceeds 2^32, the addition wraps around and the check passes. The subsequent slice access at line 875 uses Go's int-sized indexing (64-bit on amd64), causing a panic:For example,
Offset=0xFFFFFFFEandLength=3wraps to0x1, bypassing the check for any cert table larger than 1 byte.The fix replaces the single addition with an overflow-safe comparison:
Files changed:
abi/abi.go