Update Runc to 1.1.14

Changelog: https://github.com/opencontainers/runc/releases/tag/v1.1.14
This commit is contained in:
Arnaud Meukam
2024-09-04 13:51:54 +02:00
parent 09115bd093
commit f810340183
9 changed files with 311 additions and 141 deletions

View File

@@ -4,11 +4,17 @@
package utils
import (
"errors"
"fmt"
"os"
"path/filepath"
"strconv"
"strings"
_ "unsafe" // for go:linkname
"github.com/opencontainers/runc/libcontainer/system"
securejoin "github.com/cyphar/filepath-securejoin"
"golang.org/x/sys/unix"
)
@@ -115,3 +121,126 @@ func NewSockPair(name string) (parent *os.File, child *os.File, err error) {
}
return os.NewFile(uintptr(fds[1]), name+"-p"), os.NewFile(uintptr(fds[0]), name+"-c"), nil
}
// IsLexicallyInRoot is shorthand for strings.HasPrefix(path+"/", root+"/"),
// but properly handling the case where path or root are "/".
//
// NOTE: The return value only make sense if the path doesn't contain "..".
func IsLexicallyInRoot(root, path string) bool {
if root != "/" {
root += "/"
}
if path != "/" {
path += "/"
}
return strings.HasPrefix(path, root)
}
// MkdirAllInRootOpen attempts to make
//
// path, _ := securejoin.SecureJoin(root, unsafePath)
// os.MkdirAll(path, mode)
// os.Open(path)
//
// safer against attacks where components in the path are changed between
// SecureJoin returning and MkdirAll (or Open) being called. In particular, we
// try to detect any symlink components in the path while we are doing the
// MkdirAll.
//
// NOTE: Unlike os.MkdirAll, mode is not Go's os.FileMode, it is the unix mode
// (the suid/sgid/sticky bits are not the same as for os.FileMode).
//
// NOTE: If unsafePath is a subpath of root, we assume that you have already
// called SecureJoin and so we use the provided path verbatim without resolving
// any symlinks (this is done in a way that avoids symlink-exchange races).
// This means that the path also must not contain ".." elements, otherwise an
// error will occur.
//
// This is a somewhat less safe alternative to
// <https://github.com/cyphar/filepath-securejoin/pull/13>, but it should
// detect attempts to trick us into creating directories outside of the root.
// We should migrate to securejoin.MkdirAll once it is merged.
func MkdirAllInRootOpen(root, unsafePath string, mode uint32) (_ *os.File, Err error) {
// If the path is already "within" the root, use it verbatim.
fullPath := unsafePath
if !IsLexicallyInRoot(root, unsafePath) {
var err error
fullPath, err = securejoin.SecureJoin(root, unsafePath)
if err != nil {
return nil, err
}
}
subPath, err := filepath.Rel(root, fullPath)
if err != nil {
return nil, err
}
// Check for any silly mode bits.
if mode&^0o7777 != 0 {
return nil, fmt.Errorf("tried to include non-mode bits in MkdirAll mode: 0o%.3o", mode)
}
currentDir, err := os.OpenFile(root, unix.O_DIRECTORY|unix.O_CLOEXEC, 0)
if err != nil {
return nil, fmt.Errorf("open root handle: %w", err)
}
defer func() {
if Err != nil {
currentDir.Close()
}
}()
for _, part := range strings.Split(subPath, string(filepath.Separator)) {
switch part {
case "", ".":
// Skip over no-op components.
continue
case "..":
return nil, fmt.Errorf("possible breakout detected: found %q component in SecureJoin subpath %s", part, subPath)
}
nextDir, err := system.Openat(currentDir, part, unix.O_DIRECTORY|unix.O_NOFOLLOW|unix.O_CLOEXEC, 0)
switch {
case err == nil:
// Update the currentDir.
_ = currentDir.Close()
currentDir = nextDir
case errors.Is(err, unix.ENOTDIR):
// This might be a symlink or some other random file. Either way,
// error out.
return nil, fmt.Errorf("cannot mkdir in %s/%s: %w", currentDir.Name(), part, unix.ENOTDIR)
case errors.Is(err, os.ErrNotExist):
// Luckily, mkdirat will not follow trailing symlinks, so this is
// safe to do as-is.
if err := system.Mkdirat(currentDir, part, mode); err != nil {
return nil, err
}
// Open the new directory. There is a race here where an attacker
// could swap the directory with a different directory, but
// MkdirAll's fuzzy semantics mean we don't care about that.
nextDir, err := system.Openat(currentDir, part, unix.O_DIRECTORY|unix.O_NOFOLLOW|unix.O_CLOEXEC, 0)
if err != nil {
return nil, fmt.Errorf("open newly created directory: %w", err)
}
// Update the currentDir.
_ = currentDir.Close()
currentDir = nextDir
default:
return nil, err
}
}
return currentDir, nil
}
// MkdirAllInRoot is a wrapper around MkdirAllInRootOpen which closes the
// returned handle, for callers that don't need to use it.
func MkdirAllInRoot(root, unsafePath string, mode uint32) error {
f, err := MkdirAllInRootOpen(root, unsafePath, mode)
if err == nil {
_ = f.Close()
}
return err
}