WARNING: DATA RACE Read at 0x00c0007c06c8 by goroutine 286: gvisor.googlesource.com/gvisor/pkg/sentry/mm.(*MemoryManager).Brk() pkg/sentry/mm/syscalls.go:711 +0x167 gvisor.googlesource.com/gvisor/pkg/sentry/syscalls/linux.Brk() pkg/sentry/syscalls/linux/sys_mmap.go:32 +0x77 gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).executeSyscall() pkg/sentry/kernel/task_syscall.go:165 +0x407 gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke() pkg/sentry/kernel/task_syscall.go:283 +0xb4 gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter() pkg/sentry/kernel/task_syscall.go:244 +0x109 DIAGNOSIS: I0501 09:13:00.508251 36574 x:0] *************************** I0501 09:13:00.508419 36574 x:0] Args: [/syzkaller/managers/kvm-direct-overlay-host-race/current/image -root /syzkaller/managers/kvm-direct-overlay-host-race/workdir/gvisor_root -watchdog-action=panic -network=none -debug -platform=ptrace -file-access=exclusive -overlay -network=host debug -stacks ci-gvisor-kvm-direct-overlay-host-race-2] I0501 09:13:00.508526 36574 x:0] Version release-20190304.1-163-g8bfb83d0acde I0501 09:13:00.508545 36574 x:0] PID: 36574 I0501 09:13:00.508573 36574 x:0] UID: 0, GID: 0 I0501 09:13:00.508595 36574 x:0] Configuration: I0501 09:13:00.508629 36574 x:0] RootDir: /syzkaller/managers/kvm-direct-overlay-host-race/workdir/gvisor_root I0501 09:13:00.508660 36574 x:0] Platform: ptrace I0501 09:13:00.508694 36574 x:0] FileAccess: exclusive, overlay: true I0501 09:13:00.508726 36574 x:0] Network: host, logging: false I0501 09:13:00.508752 36574 x:0] Strace: false, max size: 1024, syscalls: [] I0501 09:13:00.508779 36574 x:0] *************************** D0501 09:13:00.508850 36574 x:0] Load container "/syzkaller/managers/kvm-direct-overlay-host-race/workdir/gvisor_root" "ci-gvisor-kvm-direct-overlay-host-race-2" D0501 09:13:00.516626 36574 x:0] Signal container "ci-gvisor-kvm-direct-overlay-host-race-2": signal 0 D0501 09:13:00.516719 36574 x:0] Signal sandbox "ci-gvisor-kvm-direct-overlay-host-race-2" D0501 09:13:00.516761 36574 x:0] Connecting to sandbox "ci-gvisor-kvm-direct-overlay-host-race-2" D0501 09:13:00.517199 36574 x:0] urpc: successfully marshalled 120 bytes. D0501 09:13:00.518077 36574 x:0] urpc: unmarshal success. I0501 09:13:00.518156 36574 x:0] Found sandbox "ci-gvisor-kvm-direct-overlay-host-race-2", PID: 33115 I0501 09:13:00.518190 36574 x:0] Retrieving sandbox stacks D0501 09:13:00.518202 36574 x:0] Stacks sandbox "ci-gvisor-kvm-direct-overlay-host-race-2" D0501 09:13:00.518240 36574 x:0] Connecting to sandbox "ci-gvisor-kvm-direct-overlay-host-race-2" D0501 09:13:00.518340 36574 x:0] urpc: successfully marshalled 36 bytes. D0501 09:13:00.600641 36574 x:0] urpc: unmarshal success. I0501 09:13:00.600746 36574 x:0] *** Stack dump *** goroutine 1341 [running]: gvisor.googlesource.com/gvisor/pkg/log.Stacks(0x45c801, 0xc0002d87e0, 0xc0001575c0, 0xc00027fc00) pkg/log/log.go:259 +0xb6 gvisor.googlesource.com/gvisor/runsc/boot.(*debug).Stacks(0x2427e60, 0x2427e60, 0xc000730600, 0x0, 0x0) runsc/boot/debug.go:26 +0x38 reflect.Value.call(0xc0002d87e0, 0xc0002e8198, 0x13, 0x115a58b, 0x4, 0xc0006d9eb8, 0x3, 0x3, 0x4a864e, 0x10074e0, ...) GOROOT/src/reflect/value.go:447 +0x649 reflect.Value.Call(0xc0002d87e0, 0xc0002e8198, 0x13, 0xc0006d9eb8, 0x3, 0x3, 0x0, 0x2427e60, 0x16) GOROOT/src/reflect/value.go:308 +0xc1 gvisor.googlesource.com/gvisor/pkg/urpc.(*Server).handleOne(0xc0002e6090, 0xc000320390, 0x0, 0x0) pkg/urpc/urpc.go:325 +0x63f gvisor.googlesource.com/gvisor/pkg/urpc.(*Server).handleRegistered(0xc0002e6090, 0xc000320390, 0xc0002e6090, 0xc000320390) pkg/urpc/urpc.go:420 +0x43 gvisor.googlesource.com/gvisor/pkg/urpc.(*Server).StartHandling.func1(0xc0002e6090, 0xc000320390) pkg/urpc/urpc.go:440 +0x77 created by gvisor.googlesource.com/gvisor/pkg/urpc.(*Server).StartHandling pkg/urpc/urpc.go:438 +0x6f goroutine 1 [semacquire]: sync.runtime_Semacquire(0xc00029a174) GOROOT/src/runtime/sema.go:56 +0x39 sync.(*WaitGroup).Wait(0xc00029a174) GOROOT/src/sync/waitgroup.go:130 +0xb2 gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Kernel).WaitExited(...) pkg/sentry/kernel/kernel.go:896 gvisor.googlesource.com/gvisor/runsc/boot.(*Loader).WaitExit(0xc0002368c0, 0x0, 0x0) runsc/boot/loader.go:785 +0x74 gvisor.googlesource.com/gvisor/runsc/cmd.(*Boot).Execute(0xc0002341b0, 0x12f0300, 0xc0000ce008, 0xc000240300, 0xc000208760, 0x2, 0x2, 0x0) runsc/cmd/boot.go:252 +0x12e4 github.com/google/subcommands.(*Commander).Execute(0xc000132000, 0x12f0300, 0xc0000ce008, 0xc000208760, 0x2, 0x2, 0xc0001028c0) external/com_github_google_subcommands/subcommands.go:141 +0x522 github.com/google/subcommands.Execute(...) external/com_github_google_subcommands/subcommands.go:371 main.main() runsc/main.go:245 +0x254e