panic: runtime error: slice bounds out of range [:17] with capacity 16

DIAGNOSIS:
I1219 22:10:38.252326   60068 x:0] ***************************
I1219 22:10:38.252396   60068 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 -alsologtostderr -platform=ptrace -file-access=shared -network=sandbox -TESTONLY-unsafe-nonroot debug -stacks --ps ci-gvisor-ptrace-proxy-sandbox-race-0]
I1219 22:10:38.252510   60068 x:0] Version release-20191213.0-32-g57ce26c0b465
I1219 22:10:38.252532   60068 x:0] PID: 60068
I1219 22:10:38.252571   60068 x:0] UID: 0, GID: 0
I1219 22:10:38.252611   60068 x:0] Configuration:
I1219 22:10:38.252642   60068 x:0] 		RootDir: /syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root
I1219 22:10:38.252681   60068 x:0] 		Platform: ptrace
I1219 22:10:38.252734   60068 x:0] 		FileAccess: shared, overlay: false
I1219 22:10:38.252789   60068 x:0] 		Network: sandbox, logging: false
I1219 22:10:38.252838   60068 x:0] 		Strace: false, max size: 1024, syscalls: []
I1219 22:10:38.252890   60068 x:0] ***************************
W1219 22:10:38.252913   60068 x:0] Block the TERM signal. This is only safe in tests!
D1219 22:10:38.253043   60068 x:0] Load container "/syzkaller/managers/ptrace-proxy-sandbox-race/workdir/gvisor_root" "ci-gvisor-ptrace-proxy-sandbox-race-0"
D1219 22:10:38.259844   60068 x:0] Signal container "ci-gvisor-ptrace-proxy-sandbox-race-0": signal 0
D1219 22:10:38.259977   60068 x:0] Signal sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D1219 22:10:38.260068   60068 x:0] Connecting to sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D1219 22:10:38.260523   60068 x:0] urpc: successfully marshalled 117 bytes.
I1219 22:10:38.343034   60068 x:0] Found sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0", PID: 55064
I1219 22:10:38.343177   60068 x:0] Retrieving sandbox stacks
D1219 22:10:38.343210   60068 x:0] Stacks sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
D1219 22:10:38.343280   60068 x:0] Connecting to sandbox "ci-gvisor-ptrace-proxy-sandbox-race-0"
W1219 22:10:38.343395   60068 x:0] FATAL ERROR: retrieving stacks: connecting to control server at PID 55064: connection refused
retrieving stacks: connecting to control server at PID 55064: connection refused
W1219 22:10:38.343634   60068 x:0] Failure to execute command, err: 1