iface_port_fini leaks IPv6 addresses and multicast memberships leading to address mempool exhaustion (ENOSPC/EADDRINUSE on link-local add)

[maiqueb]

Description

When a port is destroyed, grout never releases that interface's IPv6 addresses or multicast memberships - iface_port_fini frees neither.

The leaked entries accumulate in the fixed address mempool (GROUT_MEMPOOL_CHUNK_SIZE whose default is 2047). Under enough port create/destroy churn the pool fills, and the next port's automatic EUI-64 link-local can no longer be added:

ERR: ADDRESS: ip6_iface_llocal_init: iface_addr_add: No space left on device (28)

You can use the gist in https://gist.github.com/maiqueb/86e5609ac2cb8a13db0af552515e1bc5 to reproduce it locally, by executing:

CYCLES=3000 ./grout-leak-repro/repro.sh

Version

0.17.1-0.g5226d74f

[christophefontaine]

This may already be fixed by 2e2d0ca ?

@rjarry after fixing the current CI issue, we may want to tag a new version so @maiqueb can test ?

[maiqueb]

Ah, looks promising. Sure, let me know a tag, and I can check if the fix works.

[rjarry]

@christophefontaine ack, yes. See #752 for the CI flake fix.

[rjarry]

0.18.0 should have the fix.