merkledag: CumulativeSize on directories overflows

[mateon1]

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.

[mib-kd743naq]

This might be a separate ticket, but the npm subfolder in the example does not open on ipfs.io:
https://ipfs.io/ipfs/QmW4Zd911qv7uaRM2vi79YsfHvZ93skxiCxLnwpgpf7hp3/overflowdemo/npm

[Kubuxu]

@mib-kd743naq I think this directory contains data in new sharding format, #3042

[whyrusleeping]

people are using that in the wild already? i havent merged it.... o.o

[dignifiedquire]

@Kubuxu @whyrusleeping this is not related to sharding code, tested with 0.4.5-pre which does not contain #3042 and seeing the same issue when running with ipfs-whatever and ipfs object stat on the root hash of the graph generated.

ipfs object stat QmWra8edcqDmHi5TEdM3MW1GTXmpqam4bdXDW13XxxzHtA
NumLinks: 10
BlockSize: 524
LinksSize: 522
DataSize: 2
CumulativeSize: -806169813684932772