Bump runc to 1b8a1eeec3f337ab5d94f28980

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

vendor/github.com/opencontainers/runc/libcontainer/utils/utils_unix.go

@@ -0,0 +1,68 @@
+// +build !windows
+
+package utils
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+
+	"golang.org/x/sys/unix"
+)
+
+// EnsureProcHandle returns whether or not the given file handle is on procfs.
+func EnsureProcHandle(fh *os.File) error {
+	var buf unix.Statfs_t
+	if err := unix.Fstatfs(int(fh.Fd()), &buf); err != nil {
+		return fmt.Errorf("ensure %s is on procfs: %v", fh.Name(), err)
+	}
+	if buf.Type != unix.PROC_SUPER_MAGIC {
+		return fmt.Errorf("%s is not on procfs", fh.Name())
+	}
+	return nil
+}
+
+// CloseExecFrom applies O_CLOEXEC to all file descriptors currently open for
+// the process (except for those below the given fd value).
+func CloseExecFrom(minFd int) error {
+	fdDir, err := os.Open("/proc/self/fd")
+	if err != nil {
+		return err
+	}
+	defer fdDir.Close()
+
+	if err := EnsureProcHandle(fdDir); err != nil {
+		return err
+	}
+
+	fdList, err := fdDir.Readdirnames(-1)
+	if err != nil {
+		return err
+	}
+	for _, fdStr := range fdList {
+		fd, err := strconv.Atoi(fdStr)
+		// Ignore non-numeric file names.
+		if err != nil {
+			continue
+		}
+		// Ignore descriptors lower than our specified minimum.
+		if fd < minFd {
+			continue
+		}
+		// Intentionally ignore errors from unix.CloseOnExec -- the cases where
+		// this might fail are basically file descriptors that have already
+		// been closed (including and especially the one that was created when
+		// ioutil.ReadDir did the "opendir" syscall).
+		unix.CloseOnExec(fd)
+	}
+	return nil
+}
+
+// NewSockPair returns a new unix socket pair
+func NewSockPair(name string) (parent *os.File, child *os.File, err error) {
+	fds, err := unix.Socketpair(unix.AF_LOCAL, unix.SOCK_STREAM|unix.SOCK_CLOEXEC, 0)
+	if err != nil {
+		return nil, nil, err
+	}
+	return os.NewFile(uintptr(fds[1]), name+"-p"), os.NewFile(uintptr(fds[0]), name+"-c"), nil
+}