vendor: bump runc to rc94

One notable change is cgroup manager's Set now accept Resources rather
than Cgroup (see https://github.com/opencontainers/runc/pull/2906).
Modify the code accordingly.

Also update runc dependencies (as hinted by hack/lint-depdendencies.sh):

	github.com/cilium/ebpf v0.5.0
	github.com/containerd/console v1.0.2
	github.com/coreos/go-systemd/v22 v22.3.1
	github.com/godbus/dbus/v5 v5.0.4
	github.com/moby/sys/mountinfo v0.4.1
	golang.org/x/sys v0.0.0-20210426230700-d19ff857e887
	github.com/google/go-cmp v0.5.4
	github.com/kr/pretty v0.2.1
	github.com/opencontainers/runtime-spec v1.0.3-0.20210326190908-1c3f411f0417

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>

vendor/github.com/opencontainers/runc/libcontainer/cgroups/fscommon/open.go

@@ -5,7 +5,6 @@ import (
 	"strings"
 	"sync"
 
-	securejoin "github.com/cyphar/filepath-securejoin"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 	"golang.org/x/sys/unix"
@@ -17,7 +16,7 @@ const (
 )
 
 var (
-	// Set to true by fs unit tests
+	// TestMode is set to true by unit tests that need "fake" cgroupfs.
 	TestMode bool
 
 	cgroupFd     int = -1
@@ -71,12 +70,12 @@ func OpenFile(dir, file string, flags int) (*os.File, error) {
 		flags |= os.O_TRUNC | os.O_CREATE
 		mode = 0o600
 	}
+	if prepareOpenat2() != nil {
+		return openFallback(dir, file, flags, mode)
+	}
 	reldir := strings.TrimPrefix(dir, cgroupfsPrefix)
 	if len(reldir) == len(dir) { // non-standard path, old system?
-		return openWithSecureJoin(dir, file, flags, mode)
-	}
-	if prepareOpenat2() != nil {
-		return openWithSecureJoin(dir, file, flags, mode)
+		return openFallback(dir, file, flags, mode)
 	}
 
 	relname := reldir + "/" + file
@@ -93,11 +92,29 @@ func OpenFile(dir, file string, flags int) (*os.File, error) {
 	return os.NewFile(uintptr(fd), cgroupfsPrefix+relname), nil
 }
 
-func openWithSecureJoin(dir, file string, flags int, mode os.FileMode) (*os.File, error) {
-	path, err := securejoin.SecureJoin(dir, file)
+var errNotCgroupfs = errors.New("not a cgroup file")
+
+// openFallback is used when openat2(2) is not available. It checks the opened
+// file is on cgroupfs, returning an error otherwise.
+func openFallback(dir, file string, flags int, mode os.FileMode) (*os.File, error) {
+	path := dir + "/" + file
+	fd, err := os.OpenFile(path, flags, mode)
 	if err != nil {
 		return nil, err
 	}
+	if TestMode {
+		return fd, nil
+	}
+	// Check this is a cgroupfs file.
+	var st unix.Statfs_t
+	if err := unix.Fstatfs(int(fd.Fd()), &st); err != nil {
+		_ = fd.Close()
+		return nil, &os.PathError{Op: "statfs", Path: path, Err: err}
+	}
+	if st.Type != unix.CGROUP_SUPER_MAGIC && st.Type != unix.CGROUP2_SUPER_MAGIC {
+		_ = fd.Close()
+		return nil, &os.PathError{Op: "open", Path: path, Err: errNotCgroupfs}
+	}
 
-	return os.OpenFile(path, flags, mode)
+	return fd, nil
 }

vendor/github.com/opencontainers/runc/libcontainer/cgroups/fscommon/utils.go

@@ -35,22 +35,42 @@ func ParseUint(s string, base, bitSize int) (uint64, error) {
 	return value, nil
 }
 
-// GetCgroupParamKeyValue parses a space-separated "name value" kind of cgroup
-// parameter and returns its components. For example, "io_service_bytes 1234"
-// will return as "io_service_bytes", 1234.
-func GetCgroupParamKeyValue(t string) (string, uint64, error) {
-	parts := strings.Fields(t)
-	switch len(parts) {
-	case 2:
-		value, err := ParseUint(parts[1], 10, 64)
-		if err != nil {
-			return "", 0, fmt.Errorf("unable to convert to uint64: %v", err)
-		}
-
-		return parts[0], value, nil
-	default:
-		return "", 0, ErrNotValidFormat
+// ParseKeyValue parses a space-separated "name value" kind of cgroup
+// parameter and returns its key as a string, and its value as uint64
+// (ParseUint is used to convert the value). For example,
+// "io_service_bytes 1234" will be returned as "io_service_bytes", 1234.
+func ParseKeyValue(t string) (string, uint64, error) {
+	parts := strings.SplitN(t, " ", 3)
+	if len(parts) != 2 {
+		return "", 0, fmt.Errorf("line %q is not in key value format", t)
 	}
+
+	value, err := ParseUint(parts[1], 10, 64)
+	if err != nil {
+		return "", 0, fmt.Errorf("unable to convert to uint64: %v", err)
+	}
+
+	return parts[0], value, nil
+}
+
+// GetValueByKey reads a key-value pairs from the specified cgroup file,
+// and returns a value of the specified key. ParseUint is used for value
+// conversion.
+func GetValueByKey(path, file, key string) (uint64, error) {
+	content, err := ReadFile(path, file)
+	if err != nil {
+		return 0, err
+	}
+
+	lines := strings.Split(string(content), "\n")
+	for _, line := range lines {
+		arr := strings.Split(line, " ")
+		if len(arr) == 2 && arr[0] == key {
+			return ParseUint(arr[1], 10, 64)
+		}
+	}
+
+	return 0, nil
 }
 
 // GetCgroupParamUint reads a single uint64 value from the specified cgroup file.