Panic in canaries.

[cyriltovena]

While checking on a cluster I found out a canary was panicking here is stack trace:

Connecting to loki at wss://../loki/api/v1/tail?query=%7Bstream%3D%22stdout%22%2Cpod%3D%22loki-canary-7c58648dc8-xwzdr%22%7D, querying for label 'pod' with value 'loki-canary-7c58648dc8-xwzdr'
error reading websocket, will retry in 10 seconds: websocket: close 1011 (internal server error): rpc error: code = Canceled desc = grpc: the client connection is closing
Connecting to loki at wss://l...t/loki/api/v1/tail?query=%7Bstream%3D%22stdout%22%2Cpod%3D%22loki-canary-7c58648dc8-xwzdr%22%7D, querying for label 'pod' with value 'loki-canary-7c58648dc8-xwzdr'
	/src/loki/pkg/canary/comparator/comparator.go:414 +0x3a5
created by github.com/grafana/loki/pkg/canary/comparator.(*Comparator).pruneEntries
	/src/loki/pkg/canary/comparator/comparator.go:446 +0x27d
github.com/grafana/loki/pkg/canary/comparator.(*Comparator).confirmMissing(0xc000230160, {0xc00055f0e0, 0xc00055f0e0, 0x1182f00})
goroutine 1661 [running]:
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0xa4209d]
panic: runtime error: invalid memory address or nil pointer dereference

[stale]

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