panic: runtime error: index out of range

DIAGNOSIS:
I0403 13:00:08.578972    2316 x:0] ***************************
I0403 13:00:08.579103    2316 x:0] Args: [/syzkaller/managers/ptrace-proxy-sandbox-race/current/image -root /syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root -watchdog-action=panic -network=none -debug -platform=ptrace -file-access=shared -network=sandbox debug -stacks ci-gvisor-ptrace-proxy-sandbox-race-0]
I0403 13:00:08.579184    2316 x:0] Version release-20190304.1-78-gc4caccd54042
I0403 13:00:08.579202    2316 x:0] PID: 2316
I0403 13:00:08.579256    2316 x:0] UID: 0, GID: 0
I0403 13:00:08.579285    2316 x:0] Configuration:
I0403 13:00:08.579307    2316 x:0] 		RootDir: /syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root
I0403 13:00:08.579332    2316 x:0] 		Platform: ptrace
I0403 13:00:08.579359    2316 x:0] 		FileAccess: shared, overlay: false
I0403 13:00:08.579385    2316 x:0] 		Network: sandbox, logging: false
I0403 13:00:08.579406    2316 x:0] 		Strace: false, max size: 1024, syscalls: []
I0403 13:00:08.579431    2316 x:0] ***************************
D0403 13:00:08.579526    2316 x:0] Load container "/syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root" "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0403 13:00:08.590029    2316 x:0] Signal container "ci-gvisor-ptrace-proxy-sandbox-race-0": signal 0
D0403 13:00:08.590110    2316 x:0] Signal sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0403 13:00:08.590139    2316 x:0] Connecting to sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0403 13:00:08.592257    2316 x:0] urpc: successfully marshalled 117 bytes.
I0403 13:00:08.943160    2316 x:0] Found sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0", PID: 38710
I0403 13:00:08.943242    2316 x:0] Retrieving sandbox stacks
D0403 13:00:08.943274    2316 x:0] Stacks sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0403 13:00:08.943307    2316 x:0] Connecting to sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0403 13:00:08.943418    2316 x:0] urpc: successfully marshalled 36 bytes.
W0403 13:00:08.984419    2316 x:0] FATAL ERROR: retrieving stacks: getting sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0" stacks: urpc method "debug.Stacks" failed: connection reset by peer
retrieving stacks: getting sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0" stacks: urpc method "debug.Stacks" failed: connection reset by peer