[Bug]: Protobuf Any cachedValue is lost in gogoHybridHandler

[damiannolan]

Is there an existing issue for this?

• I have searched the existing issues

What happened?

Users rely on the cachedValue in Any when dealing with interface types using the sdk. Currently when a msg handler is invoked through the environment MsgRouterService (e.g. in x/gov msg execution) we lose the cachedValue on proto Any here: https://github.com/cosmos/cosmos-sdk/blob/main/baseapp/internal/protocompat/protocompat.go#L130

I suspect this is due to cachedValue behind an unexported/private field and therefore, proto.Merge cannot merge it from inReq to msg, but not 100% certain on that.

This leads to a problem when trying to use the Any later as an interface type like here: https://github.com/cosmos/ibc-go/blob/main/modules/core/02-client/types/codec.go#L77-L80

This will explode as GetCachedValue will return nil.

This surfaced in an e2e test which attempts to execute an IBC client upgrade via x/gov proposal. The ibc msg contains an Any when msg is routed through gov's msg router it loses the cachedValue and errors out.

Attaching screenshot of debugger:

Cosmos SDK Version

0.52

How to reproduce?

I reproduced the same failure seen in e2e in a unit test here for easier debugging.

It's possible to check out the following the commit and revert the diffs in msg_server.go.
cosmos/ibc-go@785dc47