panic in redisScaler

[veep]

Report

Running a brand new keda 2.9.3 install (my first keda install) on EKS, monitoring many redis celery queues, and getting occasional panics in redisScaler.

I believe it is happening only when I am applying changes to the scaler configuration (though I was making no changes to the redis trigger.)

Expected Behavior

No panics

Actual Behavior

Rarely, during application of updates to a ScaledObject with a redis trigger, I would get the panic. The operator would restart fine after a few seconds.

Steps to Reproduce the Problem

1. Run a lot of simple redis ScalerObjects
2. Apply minor changes to a lot of them

Logs from KEDA operator

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x20 pc=0x5eeea0]

goroutine 20089 [running]:
github.com/go-logr/logr.Logger.Error({{0x0?, 0x0?}, 0x2d6241e?}, {0x40930a0, 0xc000029c80}, {0x396abad, 0x19}, {0x0, 0x0, 0x0})
	/workspace/vendor/github.com/go-logr/logr/logr.go:279 +0x80
github.com/kedacore/keda/v2/pkg/scalers.(*redisScaler).GetMetricsAndActivity(0xc01a6b8540, {0x40bf988?, 0xc01abfcd00?}, {0xc019c75b40, 0xc})
	/workspace/pkg/scalers/redis_scaler.go:266 +0x1a5
github.com/kedacore/keda/v2/pkg/scaling/cache.(*ScalersCache).GetScaledObjectState(0xc01a6b85c0, {0x40bf988, 0xc01abfcd00}, 0xc01bdd2000)
	/workspace/pkg/scaling/cache/scalers_cache.go:136 +0x6fa
github.com/kedacore/keda/v2/pkg/scaling.(*scaleHandler).checkScalers(0xc000e97ef0, {0x40bf988, 0xc01abfcd00}, {0x3873b80?, 0xc01bdd2000?}, {0x40acd18, 0xc019c74928})
	/workspace/pkg/scaling/scale_handler.go:360 +0x510
github.com/kedacore/keda/v2/pkg/scaling.(*scaleHandler).startScaleLoop(0xc000e97ef0, {0x40bf988, 0xc01abfcd00}, 0xc019513680, {0x3873b80, 0xc01bdd2000}, {0x40acd18, 0xc019c74928})
	/workspace/pkg/scaling/scale_handler.go:162 +0x32a
created by github.com/kedacore/keda/v2/pkg/scaling.(*scaleHandler).HandleScalableObject
	/workspace/pkg/scaling/scale_handler.go:118 +0x71d

KEDA Version

2.9.3

Kubernetes Version

1.24

Platform

Amazon Web Services

Scaler Details

redis

Anything else?

No response

[JorTurFer]

Hi,
Thanks for reporting, it seems that the logger isn't properly assigned IDK why (yet).

[JorTurFer]

Okey, I found the issue, the logger isn't properly assigned during the scaler generation and on any error (which should be just logged) the operator panics.

[JorTurFer]

Hey @veep
The issue has been fixed, it'll be included in the next release