merkledag: CumulativeSize on directories overflows · ipfs/kubo#3440

(4 留言) (0 反應) (0 負責人)Go (13,906 star) (2,725 fork)batch import

help wantedkind/bugstatus/deferred

描述

Version information: 0.4.5

Type: bug

Priority: P4

Description:

CumulativeSize of a directory (or file) can reach ~16 EB maximum, after which it wraps around to 0B. An example showing this overflow: QmW4Zd911qv7uaRM2vi79YsfHvZ93skxiCxLnwpgpf7hp3 The directory looks like 11GB, but contains a lot of 'large' folders (like a zip bomb) + a data folder (here, the npm repo) of 723 GB. Here's the folder bomb used.

貢獻者指南

技術棧: go
領域: backend
議題類型: bug
難度: 3
預計時間: half day
活動狀態: stale
清晰度: clear
前置要求: understanding of Go integer overflowfamiliarity with IPFS merkledag
新手友善度: 35
研究方向: The bug is a uint64 overflow in CumulativeSize when directory sizes exceed ~16 EB. To reproduce, use the provided IPFS hashes. The fix likely involves checking for overflow in the size accumulation logic in the merkledag package or switching to a larger integer type. Look at the implementation of CumulativeSize in the go merkledag or go unixfs packages.