package pod /*import ( "fmt" "github.com/cilium/ebpf" "github.com/cilium/ebpf/asm" "github.com/cilium/ebpf/link" "github.com/opencontainers/runtime-spec/specs-go" "golang.org/x/sys/unix" ) // LoadAttachCgroupDeviceFilter installs eBPF device filter program to /sys/fs/cgroup/ directory. // // Requires the system to be running in cgroup2 unified-mode with kernel >= 4.15 . // // https://github.com/torvalds/linux/commit/ebc614f687369f9df99828572b1d85a7c2de3d92 func LoadAttachCgroupDeviceFilter(insts asm.Instructions, license string, dirFD int) (func() error, error) { nilCloser := func() error { return nil } spec := &ebpf.ProgramSpec{ Type: ebpf.CGroupDevice, Instructions: insts, License: license, } prog, err := ebpf.NewProgram(spec) if err != nil { return nilCloser, err } err = link.RawAttachProgram(link.RawAttachProgramOptions{ Target: dirFD, Program: prog, Attach: ebpf.AttachCGroupDevice, Flags: unix.BPF_F_ALLOW_MULTI, }) if err != nil { return nilCloser, fmt.Errorf("failed to call BPF_PROG_ATTACH (BPF_CGROUP_DEVICE, BPF_F_ALLOW_MULTI): %w", err) } closer := func() error { err = link.RawDetachProgram(link.RawDetachProgramOptions{ Target: dirFD, Program: prog, Attach: ebpf.AttachCGroupDevice, }) if err != nil { return fmt.Errorf("failed to call BPF_PROG_DETACH (BPF_CGROUP_DEVICE): %w", err) } return nil } return closer, nil } func isRWM(cgroupPermissions string) bool { r := false w := false m := false for _, rn := range cgroupPermissions { switch rn { case 'r': r = true case 'w': w = true case 'm': m = true } } return r && w && m } // the logic is from runc // https://github.com/opencontainers/runc/blob/master/libcontainer/cgroups/fs/devices_v2.go#L44 func canSkipEBPFError(devices []specs.LinuxDeviceCgroup) bool { for _, dev := range devices { if dev.Allow || !isRWM(dev.Access) { return false } } return true } */