syzbot


DATA RACE in packetmmap.(*ringBuffer).internalMappingsForFrame (2)

Status: fixed on 2025/05/16 18:16
Fix commit: a98032f6cc71 Add locking around ringbuffer fields and reserve in packetmmap endpoint.
First crash: 112d, last: 112d
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
gvisor DATA RACE in packetmmap.(*ringBuffer).internalMappingsForFrame -1 1 204d 204d 26/26 fixed on 2025/02/08 00:18

Sample crash report:
WARNING: DATA RACE
Read at 0x00c000418290 by goroutine 2427:
  gvisor.dev/gvisor/pkg/sentry/socket/netstack/packetmmap.(*ringBuffer).internalMappingsForFrame()
      pkg/sentry/socket/netstack/packetmmap/ring_buffer.go:232 +0x105
  gvisor.dev/gvisor/pkg/sentry/socket/netstack/packetmmap.(*ringBuffer).writeFrame()
      pkg/sentry/socket/netstack/packetmmap/ring_buffer.go:151 +0xad
  gvisor.dev/gvisor/pkg/sentry/socket/netstack/packetmmap.(*Endpoint).HandlePacket()
      pkg/sentry/socket/netstack/packetmmap/endpoint.go:288 +0xa15
  gvisor.dev/gvisor/pkg/tcpip/transport/packet.(*endpoint).HandlePacket()
      pkg/tcpip/transport/packet/endpoint.go:495 +0x161
  gvisor.dev/gvisor/pkg/tcpip/stack.(*nic).DeliverLinkPacket.func2()
      pkg/tcpip/stack/nic.go:826 +0x391
  gvisor.dev/gvisor/pkg/tcpip/stack.(*packetEndpointList).forEach()
      pkg/tcpip/stack/nic.go:147 +0x142
  gvisor.dev/gvisor/pkg/tcpip/stack.(*nic).DeliverLinkPacket()
      pkg/tcpip/stack/nic.go:841 +0x2e6
  gvisor.dev/gvisor/pkg/tcpip/link/nested.(*Endpoint).DeliverLinkPacket()
      pkg/tcpip/link/nested/nested.go:71 +0xc1
  gvisor.dev/gvisor/pkg/tcpip/link/packetsocket.(*Endpoint).DeliverNetworkPacket()
      pkg/tcpip/link/packetsocket/packetsocket.go:48 +0x4b
  gvisor.dev/gvisor/pkg/tcpip/link/channel.(*Endpoint).InjectInbound()
      pkg/tcpip/link/channel/channel.go:208 +0xc1
  gvisor.dev/gvisor/pkg/tcpip/link/tun.(*Device).Write()
      pkg/tcpip/link/tun/device.go:275 +0x805
  gvisor.dev/gvisor/pkg/sentry/devices/tundev.(*tunFD).Write()
      pkg/sentry/devices/tundev/tundev.go:174 +0x591
  gvisor.dev/gvisor/pkg/sentry/vfs.(*FileDescription).Write()
      pkg/sentry/vfs/file_description.go:682 +0x144
  gvisor.dev/gvisor/pkg/sentry/syscalls/linux.write()
      pkg/sentry/syscalls/linux/sys_read_write.go:347 +0xa4
  gvisor.dev/gvisor/pkg/sentry/syscalls/linux.Write()
      pkg/sentry/syscalls/linux/sys_read_write.go:316 +0x38e
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall()
      pkg/sentry/kernel/task_syscall.go:143 +0xb9e
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke()
      pkg/sentry/kernel/task_syscall.go:323 +0x84
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter()
      pkg/sentry/kernel/task_syscall.go:283 +0xc6
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall()
      pkg/sentry/kernel/task_syscall.go:258 +0x549
  gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute()
      pkg/sentry/kernel/task_run.go:269 +0x2274
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run()
      pkg/sentry/kernel/task_run.go:97 +0x41a
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start.gowrap1()
      pkg/sentry/kernel/task_start.go:412 +0x44

Previous write at 0x00c000418290 by goroutine 2425:
  gvisor.dev/gvisor/pkg/sentry/socket/netstack/packetmmap.(*ringBuffer).init()
      pkg/sentry/socket/netstack/packetmmap/ring_buffer.go:63 +0xf9
  gvisor.dev/gvisor/pkg/sentry/socket/netstack/packetmmap.(*Endpoint).Init()
      pkg/sentry/socket/netstack/packetmmap/endpoint.go:147 +0xae4
  gvisor.dev/gvisor/pkg/sentry/socket/netstack.setSockOptPacket()
      pkg/sentry/socket/netstack/netstack.go:2974 +0x907
  gvisor.dev/gvisor/pkg/sentry/socket/netstack.SetSockOpt()
      pkg/sentry/socket/netstack/netstack.go:1940 +0x365
  gvisor.dev/gvisor/pkg/sentry/socket/netstack.(*sock).SetSockOpt()
      pkg/sentry/socket/netstack/netstack.go:672 +0x6a9
  gvisor.dev/gvisor/pkg/sentry/syscalls/linux.SetSockOpt()
      pkg/sentry/syscalls/linux/sys_socket.go:551 +0x46b
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).executeSyscall()
      pkg/sentry/kernel/task_syscall.go:143 +0xb9e
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallInvoke()
      pkg/sentry/kernel/task_syscall.go:323 +0x84
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscallEnter()
      pkg/sentry/kernel/task_syscall.go:283 +0xc6
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).doSyscall()
      pkg/sentry/kernel/task_syscall.go:258 +0x549
  gvisor.dev/gvisor/pkg/sentry/kernel.(*runApp).execute()
      pkg/sentry/kernel/task_run.go:269 +0x2274
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).run()
      pkg/sentry/kernel/task_run.go:97 +0x41a
  gvisor.dev/gvisor/pkg/sentry/kernel.(*Task).Start.gowrap1()
      pkg/sentry/kernel/task_start.go:412 +0x44

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/11 02:44 gvisor e4c059533a2a 77908e5f .config console log report info ci-gvisor-systrap-1-race-cover DATA RACE in packetmmap.(*ringBuffer).internalMappingsForFrame
* Struck through repros no longer work on HEAD.