Smoltcp panics in `get_source_address_ipv6`

[dscso]

TL;DR:

I think I am having the same issue as #894, maybe creating a new release could fix it.

My whole live story:

I am sorry that I can not provide much more details, but I am using an ESP32 with embassy-net v0.4.0 (which uses internally smoltcp v0.11.0). My program is not crazy complex, it gets an IPv4 address using DHCP, and for testing I am binding to some sockets and do some DNS queries.

I have connected the ESP32 to a network with a looot of "smart" devices. On this network the ESP32 crashes in random times with the error pasted below. This crash occurs within a few dozen seconds to a few minutes. When I put the ESP32 in an isolated network without the smart devices, there seem to be no issue. I left it running over night and it worked just fine.

I tried to compile the network stack without IPv6 enabled to check if the error also occurs when IPv6 is disabled unfortunately, IPv6 seems not so easy to disable using the embassy-net crate.

!! A panic occured in '/Users/me/.cargo/registry/src/index.crates.io-6f17d22bba15001f/smoltcp-0.11.0/src/iface/interface/mod.rs', at line 882, column 14:
called `Option::unwrap()` on a `None` value

Backtrace:

0x400e3ce1
0x400e3ce1 - core::option::unwrap_failed
    at /Users/me/.rustup/toolchains/esp/lib/rustlib/src/rust/library/core/src/option.rs:1978
0x400fadcc
0x400fadcc - core::option::Option<T>::unwrap
    at /Users/me/.rustup/toolchains/esp/lib/rustlib/src/rust/library/core/src/option.rs:931
0x400f71c6
0x400f71c6 - smoltcp::iface::interface::ipv6::<impl smoltcp::iface::interface::InterfaceInner>::icmpv6_reply
    at /Users/me/.cargo/registry/src/index.crates.io-6f17d22bba15001f/smoltcp-0.11.0/src/iface/interface/ipv6.rs:336
0x400f7e4d
0x400f7e4d - smoltcp::iface::interface::InterfaceInner::process_udp
    at /Users/me/.cargo/registry/src/index.crates.io-6f17d22bba15001f/smoltcp-0.11.0/src/iface/interface/mod.rs:1174
0x400f2e04
0x400f2e04 - smoltcp::iface::interface::ipv6::<impl smoltcp::iface::interface::InterfaceInner>::process_nxt_hdr
    at ??:??
0x400dd987
0x400dd987 - smoltcp::iface::interface::ethernet::<impl smoltcp::iface::interface::InterfaceInner>::process_ethernet
    at ??:??
0x400d3b6f
0x400d3b6f - embassy_net::Inner<D>::poll
    at /Users/me/.cargo/registry/src/index.crates.io-6f17d22bba15001f/embassy-net-0.4.0/src/lib.rs:857
0x400da04f
0x400da04f - embassy_executor::raw::SyncExecutor::poll::{{closure}}
    at /Users/me/.cargo/registry/src/index.crates.io-6f17d22bba15001f/embassy-executor-0.5.0/src/raw/mod.rs:405
0x400e294f
0x400e294f - esp32_rust_mqtt::__xtensa_lx_rt_main
    at /Users/me/code/mqtt/esp32-rust-mqtt/src/main.rs:29
0x400ff592
0x400ff592 - Reset
    at /Users/me/cargo/registry/src/index.crates.io-6f17d22bba15001f/xtensa-lx-rt-0.16.0/src/lib.rs:70

[thvdveld]

This issue should be fixed with #895. Could you try using the main branch of smoltcp and see if that fixes your issue?

[dscso]

Yes I tried it now and it seems to be fixing the issue, but I have to leave it running a bit longer. Interestingly now the binary size decreased 🤔...

old version:  588,016B
new version:  578,256B

What would be the steps to create a new release so it could be used in embassy-net?

[Dirbaio]

fixed in https://github.com/smoltcp-rs/smoltcp/pull/895.