panic: invalid allocation length: 0x0

goroutine 40 [running]:
gvisor.googlesource.com/gvisor/pkg/sentry/platform/filemem.(*FileMem).Allocate(0xc000159b00, 0x0, 0x1, 0x0, 0x0, 0x0, 0x0)
	pkg/sentry/platform/filemem/filemem.go:255 +0x6ac
gvisor.googlesource.com/gvisor/pkg/sentry/platform.AllocateAndFill(0xd22980, 0xc000159b00, 0x0, 0x1, 0xd12f00, 0xc0001d1f20, 0x0, 0x0, 0x0, 0x0)
	pkg/sentry/platform/platform.go:418 +0x58
gvisor.googlesource.com/gvisor/pkg/sentry/mm.(*MemoryManager).breakCopyOnWriteLocked(0xc000448c80, 0xc0004492e8, 0x4, 0x20002000, 0x21000000, 0x4, 0x21000000, 0x0, 0x0, 0xc0004492e8)
	pkg/sentry/mm/pma.go:433 +0x352
gvisor.googlesource.com/gvisor/pkg/sentry/mm.(*MemoryManager).getPMAsLocked(0xc000448c80, 0xd1fec0, 0xc00024a000, 0xc000448cf0, 0x5, 0x20002000, 0x21000000, 0x1, 0xc000448cf0, 0x7, ...)
	pkg/sentry/mm/pma.go:142 +0x2a1
gvisor.googlesource.com/gvisor/pkg/sentry/mm.(*MemoryManager).withInternalMappings(0xc000448c80, 0xd1fec0, 0xc00024a000, 0x20002640, 0x21000000, 0x100, 0xc000531660, 0x1b, 0xc000326fc0, 0xc0005316f8)
	pkg/sentry/mm/io.go:484 +0x260
gvisor.googlesource.com/gvisor/pkg/sentry/mm.(*MemoryManager).ZeroOut(0xc000448c80, 0xd1fec0, 0xc00024a000, 0x20002640, 0x7ffff000, 0x100, 0xc000327050, 0x1000, 0x0)
	pkg/sentry/mm/io.go:205 +0x11c
gvisor.googlesource.com/gvisor/pkg/sentry/usermem.ZeroOutVec(0xd1fec0, 0xc00024a000, 0xd1ef60, 0xc000448c80, 0x0, 0x1, 0x20002640, 0x7ffff000, 0x7fffffffffffffff, 0xc000680100, ...)
	pkg/sentry/usermem/usermem.go:324 +0x179
gvisor.googlesource.com/gvisor/pkg/sentry/usermem.IOSequence.ZeroOut(0xd1ef60, 0xc000448c80, 0x0, 0x1, 0x20002640, 0x7ffff000, 0x100, 0xd1fec0, 0xc00024a000, 0x7fffffffffffffff, ...)
	pkg/sentry/usermem/usermem.go:514 +0xa4
gvisor.googlesource.com/gvisor/pkg/sentry/fs/dev.(*fullDevice).DeprecatedPreadv(0xc00038cf60, 0xd1fec0, 0xc00024a000, 0xd1ef60, 0xc000448c80, 0x0, 0x1, 0x20002640, 0x7ffff000, 0x100, ...)
	pkg/sentry/fs/dev/full.go:49 +0x82
gvisor.googlesource.com/gvisor/pkg/sentry/fs/fsutil.(*Handle).Read(0xc0001d1ee0, 0xd1fec0, 0xc00024a000, 0xc000326fc0, 0xd1ef60, 0xc000448c80, 0x0, 0x1, 0x20002640, 0x7ffff000, ...)
	pkg/sentry/fs/fsutil/handle.go:92 +0x95
gvisor.googlesource.com/gvisor/pkg/sentry/fs.(*overlayFileOperations).Read(0xc0004b82a0, 0xd1fec0, 0xc00024a000, 0xc000327050, 0xd1ef60, 0xc000448c80, 0x0, 0x1, 0x20002640, 0x7ffff000, ...)
	pkg/sentry/fs/file_overlay.go:223 +0x16c
gvisor.googlesource.com/gvisor/pkg/sentry/fs.(*File).Preadv(0xc000327050, 0xd1fec0, 0xc00024a000, 0xd1ef60, 0xc000448c80, 0x0, 0x1, 0x20002640, 0x7ffff000, 0x100, ...)
	pkg/sentry/fs/file.go:258 +0x11c
gvisor.googlesource.com/gvisor/pkg/sentry/syscalls/linux.preadv(0xc00024a000, 0xc000327050, 0xd1ef60, 0xc000448c80, 0x0, 0x1, 0x20002640, 0x7ffff000, 0x100, 0x0, ...)
	pkg/sentry/syscalls/linux/sys_read.go:296 +0x9a
gvisor.googlesource.com/gvisor/pkg/sentry/syscalls/linux.Pread64(0xc00024a000, 0x5, 0x20002640, 0xfffffede, 0x0, 0x0, 0x4002e0, 0x0, 0x0, 0x0, ...)
	pkg/sentry/syscalls/linux/sys_read.go:114 +0x2a1
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).executeSyscall(0xc00024a000, 0x11, 0x5, 0x20002640, 0xfffffede, 0x0, 0x0, 0x4002e0, 0x5, 0xc37500, ...)
	pkg/sentry/kernel/task_syscall.go:165 +0x30a
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke(0xc00024a000, 0x11, 0x5, 0x20002640, 0xfffffede, 0x0, 0x0, 0x4002e0, 0x0, 0x4002e0)
	pkg/sentry/kernel/task_syscall.go:283 +0x69
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter(0xc00024a000, 0x11, 0x5, 0x20002640, 0xfffffede, 0x0, 0x0, 0x4002e0, 0xd12c20, 0xc000531e58)
	pkg/sentry/kernel/task_syscall.go:244 +0x99
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).doSyscall(0xc00024a000, 0x2, 0xc000270040)
	pkg/sentry/kernel/task_syscall.go:219 +0x142
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*runApp).execute(0x0, 0xc00024a000, 0xd12c20, 0x0)
	pkg/sentry/kernel/task_run.go:215 +0xfda
gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).run(0xc00024a000, 0xe)
	pkg/sentry/kernel/task_run.go:91 +0x149
created by gvisor.googlesource.com/gvisor/pkg/sentry/kernel.(*Task).Start
	pkg/sentry/kernel/task_start.go:279 +0xfe