Multiaddr "/" coming from peerStore

[tabcat]

• Subsystem:

@multiformats/multiaddr
PeerStore

Severity:

Medium

Description:

#3400
InvalidParametersError: Multiaddr / was not an IPv4, IPv6, DNS, DNS4, DNS6 or DNSADDR address
@dozyio noticed the / multiaddr in the error message. I believe this is an invalid Multiaddr and should not exist/be parsable.

Steps to reproduce the error:

Not sure yet. Possible suspects:

• js-libp2p/packages/peer-store/src/utils/dedupe-addresses.ts

  Line 50 in 61d594a

  ma = ma.decapsulate(multiaddr(`/p2p/${peerId}`))

[tabcat]

Looks like this is due to a kubo/0.39.0/2896aed/docker agent constructing PeerRecord envelopes with a zero-byte multiaddr.

[lidel]

iiuc this is unfortunate regression in go-libp2p: since go-multiaddr v0.15 turned Multiaddr into a slice-backed type, a zero-value Multiaddr serializes to zero bytes, so it is likely why we started seeing zero-bytes multiaddrs being appended in various places, rather than skipped like it was implicitly happening before

fwiw opened PRs with belt and suspenders fixes upstream:

• fix(libp2p): drop empty addrs in AddrsFactory ipfs/kubo#11302
• fix(peer): drop empty addrs in peer records go-libp2p#3494

[achingbrain]

Refs: multiformats/go-multiaddr#261