panic: runtime error: index out of range

DIAGNOSIS:
I0403 15:14:13.619079   32307 x:0] ***************************
I0403 15:14:13.619225   32307 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 15:14:13.619325   32307 x:0] Version release-20190304.1-78-gc4caccd54042
I0403 15:14:13.619348   32307 x:0] PID: 32307
I0403 15:14:13.619392   32307 x:0] UID: 0, GID: 0
I0403 15:14:13.619425   32307 x:0] Configuration:
I0403 15:14:13.619460   32307 x:0] 		RootDir: /syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root
I0403 15:14:13.619481   32307 x:0] 		Platform: ptrace
I0403 15:14:13.619512   32307 x:0] 		FileAccess: shared, overlay: false
I0403 15:14:13.619561   32307 x:0] 		Network: sandbox, logging: false
I0403 15:14:13.619590   32307 x:0] 		Strace: false, max size: 1024, syscalls: []
I0403 15:14:13.619632   32307 x:0] ***************************
D0403 15:14:13.619718   32307 x:0] Load container "/syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root" "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0403 15:14:13.628816   32307 x:0] Signal container "ci-gvisor-ptrace-proxy-sandbox-race-0": signal 0
D0403 15:14:13.628897   32307 x:0] Signal sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0403 15:14:13.628945   32307 x:0] Connecting to sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0403 15:14:13.629344   32307 x:0] urpc: successfully marshalled 117 bytes.
I0403 15:14:14.278988   32307 x:0] Found sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0", PID: 60193
I0403 15:14:14.279045   32307 x:0] Retrieving sandbox stacks
D0403 15:14:14.279074   32307 x:0] Stacks sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0403 15:14:14.279099   32307 x:0] Connecting to sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D0403 15:14:14.279222   32307 x:0] urpc: successfully marshalled 36 bytes.
W0403 15:14:14.338733   32307 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