Segfault when doing role assignment

[JAORMX]

Describe the issue

When attempting to do a role assigment we get a segfault as follows:

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x20 pc=0x123fde0]

goroutine 2533 [running]:
github.com/open-feature/go-sdk-contrib/providers/go-feature-flag/pkg.genericEvaluation[...](0x0, {0x1c47918, 0x40009af950}, {0x186c40a, 0xc}, 0x0, 0x26384)
	github.com/open-feature/go-sdk-contrib/providers/go-feature-flag@v0.1.36/pkg/provider.go:206 +0x70
github.com/open-feature/go-sdk-contrib/providers/go-feature-flag/pkg.(*Provider).BooleanEvaluation(0x1567380?, {0x1c47918?, 0x40009af950?}, {0x186c40a?, 0x24?}, 0x70?, 0x0?)
	github.com/open-feature/go-sdk-contrib/providers/go-feature-flag@v0.1.36/pkg/provider.go:147 +0x6c
github.com/open-feature/go-sdk/openfeature.(*Client).evaluate(0x4000776120, {0x1c47918, 0x40009af950}, {0x186c40a, 0xc}, 0x0, {0x144a7a0, 0x2aba420}, {{0x40005c0a20, 0x24}, ...}, ...)
	github.com/open-feature/go-sdk@v1.11.0/openfeature/client.go:727 +0xbd4
github.com/open-feature/go-sdk/openfeature.(*Client).BooleanValueDetails(0x4000776120, {0x1c47918, 0x40009af950}, {0x186c40a, 0xc}, 0x0, {{0x40005c0a20?, 0x0?}, 0x40009dc240?}, {0x0, ...})
	github.com/open-feature/go-sdk@v1.11.0/openfeature/client.go:397 +0x1a8
github.com/open-feature/go-sdk/openfeature.(*Client).BooleanValue(0x0?, {0x1c47918?, 0x40009af950?}, {0x186c40a?, 0x4000ca6c08?}, 0x0, {{0x40005c0a20?, 0x0?}, 0x40009dc240?}, {0x0?, ...})
	github.com/open-feature/go-sdk@v1.11.0/openfeature/client.go:304 +0x40
github.com/open-feature/go-sdk/openfeature.(*Client).Boolean(0x1c47918?, {0x1c47918?, 0x40009af950?}, {0x186c40a?, 0x150e660?}, 0xc0?, {{0x40005c0a20?, 0x5?}, 0x40009dc240?}, {0x0?, ...})
	github.com/open-feature/go-sdk@v1.11.0/openfeature/client.go:603 +0x34
github.com/stacklok/minder/internal/flags.Bool({0x1c47918, 0x40009af950}, {0x1c64f40, 0x4000776120}, {0x186c40a, 0xc})
	github.com/stacklok/minder/internal/flags/flags.go:52 +0x74
github.com/stacklok/minder/internal/controlplane.(*Server).AssignRole(0x40005a0000, {0x1c47918, 0x40009af950}, 0x1c5f0f8?)
	github.com/stacklok/minder/internal/controlplane/handlers_authz.go:263 +0x138
github.com/stacklok/minder/pkg/api/protobuf/go/minder/v1._PermissionsService_AssignRole_Handler.func1({0x1c47918?, 0x40009af950?}, {0x16d9a00?, 0x400095bb40?})
	github.com/stacklok/minder/pkg/api/protobuf/go/minder/v1/minder_grpc.pb.go:1785 +0xd0
github.com/stacklok/minder/internal/controlplane.ProjectAuthorizationInterceptor({0x1c47918, 0x40009af950}, {0x16d9a00, 0x400095bb40}, 0x400048baa0, 0x40006fd668)
	github.com/stacklok/minder/internal/controlplane/handlers_authz.go:113 +0x324
google.golang.org/grpc.getChainUnaryHandler.func1({0x1c47918, 0x40009af950}, {0x16d9a00, 0x400095bb40})
	google.golang.org/grpc@v1.63.2/server.go:1186 +0xa0
github.com/stacklok/minder/internal/controlplane.EntityContextProjectInterceptor({0x1c47918, 0x40009aee10}, {0x16d9a00, 0x400095bb40}, 0x400048baa0, 0x400095be00)
	github.com/stacklok/minder/internal/controlplane/handlers_authz.go:75 +0x274
google.golang.org/grpc.getChainUnaryHandler.func1({0x1c47918, 0x40009aee10}, {0x16d9a00, 0x400095bb40})
	google.golang.org/grpc@v1.63.2/server.go:1186 +0xa0
github.com/stacklok/minder/internal/controlplane.TokenValidationInterceptor({0x1c47918, 0x40009ae8d0}, {0x16d9a00, 0x400095bb40}, 0x400048baa0, 0x400095bcc0)
	github.com/stacklok/minder/internal/controlplane/handlers_token.go:80 +0x494
google.golang.org/grpc.getChainUnaryHandler.func1({0x1c47918, 0x40009ae8d0}, {0x16d9a00, 0x400095bb40})
	google.golang.org/grpc@v1.63.2/server.go:1186 +0xa0
github.com/stacklok/minder/internal/controlplane.(*Server).StartGRPCServer.Interceptor.func3({0x1c47918, 0x40009ae0f0}, {0x16d9a00, 0x400095bb40}, 0x400048baa0, 0x400095bc80)
	github.com/stacklok/minder/internal/logger/logging_interceptor.go:81 +0x330
google.golang.org/grpc.getChainUnaryHandler.func1({0x1c47918, 0x40009ae0f0}, {0x16d9a00, 0x400095bb40})
	google.golang.org/grpc@v1.63.2/server.go:1186 +0xa0
github.com/stacklok/minder/internal/controlplane.(*Server).StartGRPCServer.SanitizingInterceptor.func2({0x1c47918?, 0x40009ae0f0?}, {0x16d9a00?, 0x400095bb40?}, 0x400048baa0?, 0x40006fd668?)
	github.com/stacklok/minder/internal/util/statuses.go:183 +0x34
google.golang.org/grpc.NewServer.chainUnaryServerInterceptors.chainUnaryInterceptors.func1({0x1c47918, 0x40009ae0f0}, {0x16d9a00, 0x400095bb40}, 0x400048baa0, 0x17bc360?)
	google.golang.org/grpc@v1.63.2/server.go:1177 +0x88
github.com/stacklok/minder/pkg/api/protobuf/go/minder/v1._PermissionsService_AssignRole_Handler({0x184c220, 0x40005a0000}, {0x1c47918, 0x40009ae0f0}, 0x40007ce280, 0x400037f180)
	github.com/stacklok/minder/pkg/api/protobuf/go/minder/v1/minder_grpc.pb.go:1787 +0x148
google.golang.org/grpc.(*Server).processUnaryRPC(0x400074c800, {0x1c47918, 0x40009ae000}, {0x1c543a0, 0x40006d0600}, 0x400098e240, 0x40008baea0, 0x2c3f290, 0x0)
	google.golang.org/grpc@v1.63.2/server.go:1369 +0xb58
google.golang.org/grpc.(*Server).handleStream(0x400074c800, {0x1c543a0, 0x40006d0600}, 0x400098e240)
	google.golang.org/grpc@v1.63.2/server.go:1780 +0xb20
google.golang.org/grpc.(*Server).serveStreams.func2.1()
	google.golang.org/grpc@v1.63.2/server.go:1019 +0x8c
created by google.golang.org/grpc.(*Server).serveStreams.func2 in goroutine 2532
	google.golang.org/grpc@v1.63.2/server.go:1030 +0x13c

Seems to be an issue with the recently included feature flags.

To Reproduce

minder project role grant -r editor -s <some subject>

this happens if no feature flags configuration is present.

What version are you using?

No response

[JAORMX]

We mitigated this by not setting the environment variable that enables the feature flag functionality.

[blkt]

Issue lies in this line not doing what's intended.
Specifically, flagProvider variable declared here is an interface (see here), so checking for null values gets weird in Go.