github
/
k3s
mirror of https://github.com/k3s-io/k3s
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

Fixed subpath in containerized kubelet. 

IsNotMountPoint should return no error when the checked directory does not
exists - missing directory can't be mounted. Therefore containerized
kubelet should check if the target exists first before resolving symlinks.
EvalHostSymlinks() returns indistinguishible error in case the path does
not exist.
pull/58/head
Jan Safranek 2018-10-09 13:11:23 +02:00
parent 9ba74cb5b5
commit 0b8c472578
2 changed files with 21 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
pkg/util/mount/mount.go
View File

@ -251,14 +251,9 @@ func GetDeviceNameFromMount(mounter Interface, mountPath string) (string, int, e
// It is more extensive than IsLikelyNotMountPoint
// and it detects bind mounts in linux
func IsNotMountPoint(mounter Interface, file string) (bool, error) {
// Resolve any symlinks in file, kernel would do the same and use the resolved path in /proc/mounts
resolvedFile, err := mounter.EvalHostSymlinks(file)
if err != nil {
return true, err
}
// IsLikelyNotMountPoint provides a quick check
// to determine whether file IS A mountpoint
notMnt, notMntErr := mounter.IsLikelyNotMountPoint(resolvedFile)
notMnt, notMntErr := mounter.IsLikelyNotMountPoint(file)
if notMntErr != nil && os.IsPermission(notMntErr) {
// We were not allowed to do the simple stat() check, e.g. on NFS with
// root_squash. Fall back to /proc/mounts check below.
@ -272,6 +267,13 @@ func IsNotMountPoint(mounter Interface, file string) (bool, error) {
if notMnt == false {
return notMnt, nil
}
// Resolve any symlinks in file, kernel would do the same and use the resolved path in /proc/mounts
resolvedFile, err := mounter.EvalHostSymlinks(file)
if err != nil {
return true, err
}
// check all mountpoints since IsLikelyNotMountPoint
// is not reliable for some mountpoint types
mountPoints, mountPointsErr := mounter.List()

19
pkg/util/mount/nsenter_mount.go
View File

@ -166,15 +166,22 @@ func (n *NsenterMounter) IsLikelyNotMountPoint(file string) (bool, error) {
glog.V(5).Infof("findmnt: directory %s does not exist", file)
return true, err
}
// Resolve any symlinks in file, kernel would do the same and use the resolved path in /proc/mounts
resolvedFile, err := n.EvalHostSymlinks(file)
if err != nil {
return true, err
}
// Add --first-only option: since we are testing for the absence of a mountpoint, it is sufficient to get only
// the first of multiple possible mountpoints using --first-only.
// Also add fstype output to make sure that the output of target file will give the full path
// TODO: Need more refactoring for this function. Track the solution with issue #26996
args := []string{"-o", "target,fstype", "--noheadings", "--first-only", "--target", file}
args := []string{"-o", "target,fstype", "--noheadings", "--first-only", "--target", resolvedFile}
glog.V(5).Infof("nsenter findmnt args: %v", args)
out, err := n.ne.Exec("findmnt", args).CombinedOutput()
if err != nil {
glog.V(2).Infof("Failed findmnt command for path %s: %s %v", file, out, err)
glog.V(2).Infof("Failed findmnt command for path %s: %s %v", resolvedFile, out, err)
// Different operating systems behave differently for paths which are not mount points.
// On older versions (e.g. 2.20.1) we'd get error, on newer ones (e.g. 2.26.2) we'd get "/".
// It's safer to assume that it's not a mount point.
@ -185,13 +192,13 @@ func (n *NsenterMounter) IsLikelyNotMountPoint(file string) (bool, error) {
return false, err
}
glog.V(5).Infof("IsLikelyNotMountPoint findmnt output for path %s: %v:", file, mountTarget)
glog.V(5).Infof("IsLikelyNotMountPoint findmnt output for path %s: %v:", resolvedFile, mountTarget)
if mountTarget == file {
glog.V(5).Infof("IsLikelyNotMountPoint: %s is a mount point", file)
if mountTarget == resolvedFile {
glog.V(5).Infof("IsLikelyNotMountPoint: %s is a mount point", resolvedFile)
return false, nil
}
glog.V(5).Infof("IsLikelyNotMountPoint: %s is not a mount point", file)
glog.V(5).Infof("IsLikelyNotMountPoint: %s is not a mount point", resolvedFile)
return true, nil
}