Bump github.com/opencontainers/runc from 1.0.0 to 1.0.1

Bumps [github.com/opencontainers/runc](https://github.com/opencontainers/runc) from 1.0.0 to 1.0.1.
- [Release notes](https://github.com/opencontainers/runc/releases)
- [Commits](https://github.com/opencontainers/runc/compare/v1.0.0...v1.0.1)

---
updated-dependencies:
- dependency-name: github.com/opencontainers/runc
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

vendor/github.com/opencontainers/runc/libcontainer/user/user.go

@@ -2,6 +2,7 @@ package user
 
 import (
 	"bufio"
+	"bytes"
 	"errors"
 	"fmt"
 	"io"
@@ -55,11 +56,11 @@ type IDMap struct {
 	Count    int64
 }
 
-func parseLine(line string, v ...interface{}) {
-	parseParts(strings.Split(line, ":"), v...)
+func parseLine(line []byte, v ...interface{}) {
+	parseParts(bytes.Split(line, []byte(":")), v...)
 }
 
-func parseParts(parts []string, v ...interface{}) {
+func parseParts(parts [][]byte, v ...interface{}) {
 	if len(parts) == 0 {
 		return
 	}
@@ -75,16 +76,16 @@ func parseParts(parts []string, v ...interface{}) {
 		// This is legit.
 		switch e := v[i].(type) {
 		case *string:
-			*e = p
+			*e = string(p)
 		case *int:
 			// "numbers", with conversion errors ignored because of some misbehaving configuration files.
-			*e, _ = strconv.Atoi(p)
+			*e, _ = strconv.Atoi(string(p))
 		case *int64:
-			*e, _ = strconv.ParseInt(p, 10, 64)
+			*e, _ = strconv.ParseInt(string(p), 10, 64)
 		case *[]string:
 			// Comma-separated lists.
-			if p != "" {
-				*e = strings.Split(p, ",")
+			if len(p) != 0 {
+				*e = strings.Split(string(p), ",")
 			} else {
 				*e = []string{}
 			}
@@ -128,8 +129,8 @@ func ParsePasswdFilter(r io.Reader, filter func(User) bool) ([]User, error) {
 	)
 
 	for s.Scan() {
-		line := strings.TrimSpace(s.Text())
-		if line == "" {
+		line := bytes.TrimSpace(s.Bytes())
+		if len(line) == 0 {
 			continue
 		}
 
@@ -179,15 +180,53 @@ func ParseGroupFilter(r io.Reader, filter func(Group) bool) ([]Group, error) {
 	if r == nil {
 		return nil, fmt.Errorf("nil source for group-formatted data")
 	}
+	rd := bufio.NewReader(r)
+	out := []Group{}
 
-	var (
-		s   = bufio.NewScanner(r)
-		out = []Group{}
-	)
+	// Read the file line-by-line.
+	for {
+		var (
+			isPrefix  bool
+			wholeLine []byte
+			err       error
+		)
 
-	for s.Scan() {
-		text := s.Text()
-		if text == "" {
+		// Read the next line. We do so in chunks (as much as reader's
+		// buffer is able to keep), check if we read enough columns
+		// already on each step and store final result in wholeLine.
+		for {
+			var line []byte
+			line, isPrefix, err = rd.ReadLine()
+
+			if err != nil {
+				// We should return no error if EOF is reached
+				// without a match.
+				if err == io.EOF { //nolint:errorlint // comparison with io.EOF is legit, https://github.com/polyfloyd/go-errorlint/pull/12
+					err = nil
+				}
+				return out, err
+			}
+
+			// Simple common case: line is short enough to fit in a
+			// single reader's buffer.
+			if !isPrefix && len(wholeLine) == 0 {
+				wholeLine = line
+				break
+			}
+
+			wholeLine = append(wholeLine, line...)
+
+			// Check if we read the whole line already.
+			if !isPrefix {
+				break
+			}
+		}
+
+		// There's no spec for /etc/passwd or /etc/group, but we try to follow
+		// the same rules as the glibc parser, which allows comments and blank
+		// space at the beginning of a line.
+		wholeLine = bytes.TrimSpace(wholeLine)
+		if len(wholeLine) == 0 || wholeLine[0] == '#' {
 			continue
 		}
 
@@ -197,17 +236,12 @@ func ParseGroupFilter(r io.Reader, filter func(Group) bool) ([]Group, error) {
 		//  root:x:0:root
 		//  adm:x:4:root,adm,daemon
 		p := Group{}
-		parseLine(text, &p.Name, &p.Pass, &p.Gid, &p.List)
+		parseLine(wholeLine, &p.Name, &p.Pass, &p.Gid, &p.List)
 
 		if filter == nil || filter(p) {
 			out = append(out, p)
 		}
 	}
-	if err := s.Err(); err != nil {
-		return nil, err
-	}
-
-	return out, nil
 }
 
 type ExecUser struct {
@@ -278,7 +312,7 @@ func GetExecUser(userSpec string, defaults *ExecUser, passwd, group io.Reader) (
 
 	// Allow for userArg to have either "user" syntax, or optionally "user:group" syntax
 	var userArg, groupArg string
-	parseLine(userSpec, &userArg, &groupArg)
+	parseLine([]byte(userSpec), &userArg, &groupArg)
 
 	// Convert userArg and groupArg to be numeric, so we don't have to execute
 	// Atoi *twice* for each iteration over lines.
@@ -496,8 +530,8 @@ func ParseSubIDFilter(r io.Reader, filter func(SubID) bool) ([]SubID, error) {
 	)
 
 	for s.Scan() {
-		line := strings.TrimSpace(s.Text())
-		if line == "" {
+		line := bytes.TrimSpace(s.Bytes())
+		if len(line) == 0 {
 			continue
 		}
 
@@ -549,14 +583,14 @@ func ParseIDMapFilter(r io.Reader, filter func(IDMap) bool) ([]IDMap, error) {
 	)
 
 	for s.Scan() {
-		line := strings.TrimSpace(s.Text())
-		if line == "" {
+		line := bytes.TrimSpace(s.Bytes())
+		if len(line) == 0 {
 			continue
 		}
 
 		// see: man 7 user_namespaces
 		p := IDMap{}
-		parseParts(strings.Fields(line), &p.ID, &p.ParentID, &p.Count)
+		parseParts(bytes.Fields(line), &p.ID, &p.ParentID, &p.Count)
 
 		if filter == nil || filter(p) {
 			out = append(out, p)