Ref struct in scanned assembly results in app crash at startup, if sagas are present

[SimonCropp]

Describe the bug

since MakeGenericType is used without checking if the type constraints are met

Steps to reproduce

have a Ref struct in message scanning

NSB 9.2.2.0
.net: 8

Backported to

• 9.1.2
• 9.0.4
• 8.2.4
• 7.8.6

[SimonCropp]

it is a side effect of

transport.RouteToEndpoint(Assembly)

it doesn't seem to respect the message convention. so if u have any type in that assembly that conflicts with a type constraint it will blow up.

repo: https://github.com/SimonCropp/NSBGreedyRoutTo

[SimonCropp]

stack:

System.Exception: Failed to evaluate Message convention. See inner exception for details.
 ---> System.ArgumentException: GenericArguments[0], 'My.Messages.RefStruct', on 'NServiceBus.IHandleTimeouts`1[T]' violates the constraint of type 'T'.
 ---> System.TypeLoadException: GenericArguments[0], 'My.Messages.RefStruct', on 'NServiceBus.IHandleTimeouts`1[T]' violates the constraint of type parameter 'T'.
   at System.RuntimeTypeHandle.Instantiate(RuntimeType inst)
   at System.RuntimeType.MakeGenericType(Type[] instantiation)
   --- End of inner exception stack trace ---
   at System.RuntimeType.ValidateGenericArguments(MemberInfo definition, RuntimeType[] genericArguments, Exception e)
   at System.RuntimeType.MakeGenericType(Type[] instantiation)
   at NServiceBus.Features.Sagas.IsTypeATimeoutHandledByAnySaga(Type type, IEnumerable`1 sagas) in /_/src/NServiceBus.Core/Sagas/Sagas.cs:line 107
   at NServiceBus.Features.Sagas.<>c__DisplayClass0_0.<.ctor>b__4(Type t) in /_/src/NServiceBus.Core/Sagas/Sagas.cs:line 25
   at NServiceBus.Conventions.<>c__DisplayClass2_0.<IsInSystemConventionList>b__0(Func`2 isSystemMessageAction) in /_/src/NServiceBus.Core/Conventions/Conventions.cs:line 90
   at System.Linq.Enumerable.Any[TSource](IEnumerable`1 source, Func`2 predicate)
   at NServiceBus.Conventions.IsInSystemConventionList(Type t) in /_/src/NServiceBus.Core/Conventions/Conventions.cs:line 90
   at NServiceBus.Conventions.<IsMessageType>b__1_0(RuntimeTypeHandle typeHandle) in /_/src/NServiceBus.Core/Conventions/Conventions.cs:line 37
   at System.Collections.Concurrent.ConcurrentDictionary`2.GetOrAdd(TKey key, Func`2 valueFactory)
   at NServiceBus.Conventions.ConventionCache.ApplyConvention(Type type, Func`2 action) in /_/src/NServiceBus.Core/Conventions/Conventions.cs:line 266
   at NServiceBus.Conventions.IsMessageType(Type t) in /_/src/NServiceBus.Core/Conventions/Conventions.cs:line 32
   --- End of inner exception stack trace ---
   at NServiceBus.Conventions.IsMessageType(Type t) in /_/src/NServiceBus.Core/Conventions/Conventions.cs:line 80
   at NServiceBus.AssemblyRouteSource.<>c__DisplayClass3_0.<GenerateRoutes>b__0(Type t) in /_/src/NServiceBus.Core/Routing/AssemblyRouteSource.cs:line 23
   at System.Linq.Enumerable.WhereSelectArrayIterator`2.ToArray()
   at NServiceBus.AssemblyRouteSource.GenerateRoutes(Conventions conventions) in /_/src/NServiceBus.Core/Routing/AssemblyRouteSource.cs:line 22
   at NServiceBus.Features.ConfiguredUnicastRoutes.Apply(UnicastRoutingTable unicastRoutingTable, Conventions conventions) in /_/src/NServiceBus.Core/Routing/ConfiguredUnicastRoutes.cs:line 23
   at NServiceBus.RoutingComponent.Initialize(Configuration configuration, Configuration receiveConfiguration, Conventions conventions, PipelineSettings pipelineSettings, Configuration hostingConfiguration, TransportSeam transportSeam) in /_/src/NServiceBus.Core/Routing/RoutingComponent.cs:line 36
   at NServiceBus.EndpointCreator.Configure() in /_/src/NServiceBus.Core/EndpointCreator.cs:line 86
   at NServiceBus.EndpointCreator.Create(EndpointConfiguration endpointConfiguration, IServiceCollection serviceCollection) in /_/src/NServiceBus.Core/EndpointCreator.cs:line 34
   at NServiceBus.Endpoint.Create(EndpointConfiguration configuration, CancellationToken cancellationToken) in /_/src/NServiceBus.Core/Endpoint.cs:line 24

[SimonCropp]

@boblangley what was the outcome of the Triage?

[boblangley]

We ranked it as a priority bug, but not critical. This means we have queued it for work with the other priority bugs and a team will take this on when one becomes available to work on it. I don't have an ETA, the team should say something on this issue when they start working on it.

[andreasohlund]

Thanks @SimonCropp we are working on a fix for this #7187

[SimonCropp]

@andreasohlund thanks