DATA RACE in packetmmap.(*Endpoint).marshalFrameHeader (2)

Status: fixed on 2025/05/07 21:58
Fix commit: f56929a6872c Lock around grabbing the version and hdrLen in packetmmap.
First crash: 486d, last: 486d
▶ ▼ Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
gvisor DATA RACE in packetmmap.(*Endpoint).marshalFrameHeader -1 syz, C 6 490d 490d 26/26 fixed on 2025/05/02 08:36

Sample crash report:
WARNING: DATA RACE
Read at 0x00c0003823e8 by goroutine 5743:
  gvisor.dev/gvisor/pkg/sentry/socket/netstack/packetmmap.(*Endpoint).marshalFrameHeader()
      pkg/sentry/socket/netstack/packetmmap/endpoint.go:438 +0x9a
  gvisor.dev/gvisor/pkg/sentry/socket/netstack/packetmmap.(*Endpoint).HandlePacket()
      pkg/sentry/socket/netstack/packetmmap/endpoint.go:282 +0x7a4
  gvisor.dev/gvisor/pkg/tcpip/transport/packet.(*endpoint).HandlePacket()
      pkg/tcpip/transport/packet/endpoint.go:495 +0x122
  gvisor.dev/gvisor/pkg/tcpip/stack.(*nic).DeliverLinkPacket.func2()
      pkg/tcpip/stack/nic.go:826 +0x311
  gvisor.dev/gvisor/pkg/tcpip/stack.(*packetEndpointList).forEach()
      pkg/tcpip/stack/nic.go:147 +0xf3
  gvisor.dev/gvisor/pkg/tcpip/stack.(*nic).DeliverLinkPacket()
      pkg/tcpip/stack/nic.go:841 +0x284
  gvisor.dev/gvisor/pkg/tcpip/link/nested.(*Endpoint).DeliverLinkPacket()
      pkg/tcpip/link/nested/nested.go:71 +0x98
  gvisor.dev/gvisor/pkg/tcpip/link/packetsocket.(*endpoint).DeliverNetworkPacket()
      pkg/tcpip/link/packetsocket/packetsocket.go:45 +0x3a
  gvisor.dev/gvisor/pkg/tcpip/link/channel.(*Endpoint).InjectInbound()
      pkg/tcpip/link/channel/channel.go:208 +0x98
  gvisor.dev/gvisor/pkg/tcpip/link/tun.(*Device).Write()
      pkg/tcpip/link/tun/device.go:250 +0xe91
  gvisor.dev/gvisor/pkg/sentry/devices/tundev.(*tunFD).Write()
      pkg/sentry/devices/tundev/tundev.go:163 +0x3c4
  gvisor.dev/gvisor/pkg/sentry/vfs.(*FileDescription).Write()
      pkg/sentry/vfs/file_description.go:682 +0x118
  gvisor.dev/gvisor/pkg/sentry/syscalls/linux.write()
      pkg/sentry/syscalls/linux/sys_read_write.go:347 +0x90
  gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Write()
      pkg/sentry/syscalls/linux/sys_read_write.go:316 +0x2b1
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall()
      pkg/sentry/kernel/task_syscall.go:143 +0x994
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke()
      pkg/sentry/kernel/task_syscall.go:323 +0x71
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter()
      pkg/sentry/kernel/task_syscall.go:283 +0x93
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall()
      pkg/sentry/kernel/task_syscall.go:258 +0x4af
  gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute()
      pkg/sentry/kernel/task_run.go:269 +0x1fa7
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run()
      pkg/sentry/kernel/task_run.go:97 +0x4fa
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start.gowrap1()
      pkg/sentry/kernel/task_start.go:412 +0x44

Previous write at 0x00c0003823e8 by goroutine 5734:
  gvisor.dev/gvisor/pkg/sentry/socket/netstack/packetmmap.(*Endpoint).Init()
      pkg/sentry/socket/netstack/packetmmap/endpoint.go:107 +0x272
  gvisor.dev/gvisor/pkg/sentry/socket/netstack.setSockOptPacket()
      pkg/sentry/socket/netstack/netstack.go:2974 +0xc5e
  gvisor.dev/gvisor/pkg/sentry/socket/netstack.SetSockOpt()
      pkg/sentry/socket/netstack/netstack.go:1940 +0x2e4
  gvisor.dev/gvisor/pkg/sentry/socket/netstack.(*sock).SetSockOpt()
      pkg/sentry/socket/netstack/netstack.go:672 +0x607
  gvisor.dev/gvisor/pkg/sentry/syscalls/linux.SetSockOpt()
      pkg/sentry/syscalls/linux/sys_socket.go:551 +0x3b4
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall()
      pkg/sentry/kernel/task_syscall.go:143 +0x994
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke()
      pkg/sentry/kernel/task_syscall.go:323 +0x71
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter()
      pkg/sentry/kernel/task_syscall.go:283 +0x93
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall()
      pkg/sentry/kernel/task_syscall.go:258 +0x4af
  gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute()
      pkg/sentry/kernel/task_run.go:269 +0x1fa7
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run()
      pkg/sentry/kernel/task_run.go:97 +0x4fa
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start.gowrap1()
      pkg/sentry/kernel/task_start.go:412 +0x44

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/04 05:56 gvisor 5c4b4f51c72e d7f099d1 .config console log report syz / log C ci-gvisor-systrap-1-race DATA RACE in packetmmap.(*Endpoint).marshalFrameHeader
2025/05/04 05:37 gvisor 5c4b4f51c72e d7f099d1 .config console log report syz / log C ci-gvisor-ptrace-1-race-cover DATA RACE in packetmmap.(*Endpoint).marshalFrameHeader
2025/05/04 08:09 gvisor 5c4b4f51c72e d7f099d1 .config console log report syz / log ci-gvisor-ptrace-2-race-cover DATA RACE in packetmmap.(*Endpoint).marshalFrameHeader
* Struck through repros no longer work on HEAD.