Revert "Merge pull request 101888 from kolyshkin/update-runc-rc94"

This reverts commit b1b06fe0a4, reversing
changes made to 382a33986b.

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

@@ -5,6 +5,7 @@ import (
 	"strings"
 	"sync"
 
+	securejoin "github.com/cyphar/filepath-securejoin"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 	"golang.org/x/sys/unix"
@@ -16,7 +17,7 @@ const (
 )
 
 var (
-	// TestMode is set to true by unit tests that need "fake" cgroupfs.
+	// Set to true by fs unit tests
 	TestMode bool
 
 	cgroupFd     int = -1
@@ -70,12 +71,12 @@ 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 openFallback(dir, file, flags, mode)
+		return openWithSecureJoin(dir, file, flags, mode)
+	}
+	if prepareOpenat2() != nil {
+		return openWithSecureJoin(dir, file, flags, mode)
 	}
 
 	relname := reldir + "/" + file
@@ -92,29 +93,11 @@ func OpenFile(dir, file string, flags int) (*os.File, error) {
 	return os.NewFile(uintptr(fd), cgroupfsPrefix+relname), nil
 }
 
-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)
+func openWithSecureJoin(dir, file string, flags int, mode os.FileMode) (*os.File, error) {
+	path, err := securejoin.SecureJoin(dir, file)
 	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 fd, nil
+	return os.OpenFile(path, flags, mode)
 }

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

@@ -35,42 +35,22 @@ func ParseUint(s string, base, bitSize int) (uint64, error) {
 	return value, nil
 }
 
-// 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)
+// 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 0, nil
+		return parts[0], value, nil
+	default:
+		return "", 0, ErrNotValidFormat
+	}
 }
 
 // GetCgroupParamUint reads a single uint64 value from the specified cgroup file.