From f09346578021c12069b6deb9487a1462b8d28a83 Mon Sep 17 00:00:00 2001
From: Nalin Dahyabhai <nalin@redhat.com>
Date: Thu, 21 Nov 2019 15:32:41 -0500
Subject: [PATCH 1/3] bind: don't complain about missing mountpoints
When we go to unmount a tree of mounts, if one of the directories isn't
there, instead of returning an error as before, log a debug message and
keep going.
Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>
---
bind/mount.go | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/bind/mount.go b/bind/mount.go
index e1ae323b9..adde901fd 100644
--- a/bind/mount.go
+++ b/bind/mount.go
@@ -264,6 +264,10 @@ func UnmountMountpoints(mountpoint string, mountpointsToRemove []string) error {
mount := getMountByID(id)
// check if this mountpoint is mounted
if err := unix.Lstat(mount.Mountpoint, &st); err != nil {
+ if os.IsNotExist(err) {
+ logrus.Debugf("mountpoint %q is not present(?), skipping", mount.Mountpoint)
+ continue
+ }
return errors.Wrapf(err, "error checking if %q is mounted", mount.Mountpoint)
}
if mount.Major != int(unix.Major(st.Dev)) || mount.Minor != int(unix.Minor(st.Dev)) {
From c5fb681a6082b78c422eb3531667dc6d607a9355 Mon Sep 17 00:00:00 2001
From: Nalin Dahyabhai <nalin@redhat.com>
Date: Fri, 22 Nov 2019 14:22:26 -0500
Subject: [PATCH 2/3] chroot: Unmount with MNT_DETACH instead of
UnmountMountpoints()
Unmounting the rootfs with MNT_DETACH should unmount everything below
it, so we don't need to use the more exhaustive method that our bind
package uses for its bind mounts.
Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>
---
chroot/run.go | 25 +++++++++++++++----------
1 file changed, 15 insertions(+), 10 deletions(-)
diff --git a/chroot/run.go b/chroot/run.go
index fbccbcdb0..76ac78d1f 100644
--- a/chroot/run.go
+++ b/chroot/run.go
@@ -15,6 +15,7 @@ import (
"strings"
"sync"
"syscall"
+ "time"
"unsafe"
"github.com/containers/buildah/bind"
@@ -1002,12 +1003,19 @@ func isDevNull(dev os.FileInfo) bool {
// callback that will clean up its work.
func setupChrootBindMounts(spec *specs.Spec, bundlePath string) (undoBinds func() error, err error) {
var fs unix.Statfs_t
- removes := []string{}
undoBinds = func() error {
- if err2 := bind.UnmountMountpoints(spec.Root.Path, removes); err2 != nil {
- logrus.Warnf("pkg/chroot: error unmounting %q: %v", spec.Root.Path, err2)
- if err == nil {
- err = err2
+ if err2 := unix.Unmount(spec.Root.Path, unix.MNT_DETACH); err2 != nil {
+ retries := 0
+ for (err2 == unix.EBUSY || err2 == unix.EAGAIN) && retries < 50 {
+ time.Sleep(50 * time.Millisecond)
+ err2 = unix.Unmount(spec.Root.Path, unix.MNT_DETACH)
+ retries++
+ }
+ if err2 != nil {
+ logrus.Warnf("pkg/chroot: error unmounting %q (retried %d times): %v", spec.Root.Path, retries, err2)
+ if err == nil {
+ err = err2
+ }
}
}
return err
@@ -1096,6 +1104,7 @@ func setupChrootBindMounts(spec *specs.Spec, bundlePath string) (undoBinds func(
// Add /sys/fs/selinux to the set of masked paths, to ensure that we don't have processes
// attempting to interact with labeling, when they aren't allowed to do so.
spec.Linux.MaskedPaths = append(spec.Linux.MaskedPaths, "/sys/fs/selinux")
+
// Bind mount in everything we've been asked to mount.
for _, m := range spec.Mounts {
// Skip anything that we just mounted.
@@ -1141,13 +1150,11 @@ func setupChrootBindMounts(spec *specs.Spec, bundlePath string) (undoBinds func(
if !os.IsNotExist(err) {
return undoBinds, errors.Wrapf(err, "error examining %q for mounting in mount namespace", target)
}
- // The target isn't there yet, so create it, and make a
- // note to remove it later.
+ // The target isn't there yet, so create it.
if srcinfo.IsDir() {
if err = os.MkdirAll(target, 0111); err != nil {
return undoBinds, errors.Wrapf(err, "error creating mountpoint %q in mount namespace", target)
}
- removes = append(removes, target)
} else {
if err = os.MkdirAll(filepath.Dir(target), 0111); err != nil {
return undoBinds, errors.Wrapf(err, "error ensuring parent of mountpoint %q (%q) is present in mount namespace", target, filepath.Dir(target))
@@ -1157,7 +1164,6 @@ func setupChrootBindMounts(spec *specs.Spec, bundlePath string) (undoBinds func(
return undoBinds, errors.Wrapf(err, "error creating mountpoint %q in mount namespace", target)
}
file.Close()
- removes = append(removes, target)
}
}
requestFlags := bindFlags
@@ -1266,7 +1272,6 @@ func setupChrootBindMounts(spec *specs.Spec, bundlePath string) (undoBinds func(
if err := os.Mkdir(roEmptyDir, 0700); err != nil {
return undoBinds, errors.Wrapf(err, "error creating empty directory %q", roEmptyDir)
}
- removes = append(removes, roEmptyDir)
}
// Set up any masked paths that we need to. If we're running inside of
From ec1be6a51941e10b5316c911ef97c88940f7c095 Mon Sep 17 00:00:00 2001
From: Nalin Dahyabhai <nalin@redhat.com>
Date: Fri, 22 Nov 2019 14:52:25 -0500
Subject: [PATCH 3/3] overlay.bats typo: fuse-overlays should be fuse-overlayfs
Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>
---
tests/overlay.bats | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tests/overlay.bats b/tests/overlay.bats
index 04056f680..7cc2d0c62 100644
--- a/tests/overlay.bats
+++ b/tests/overlay.bats
@@ -3,14 +3,14 @@
load helpers
@test "overlay specific level" {
- if test \! -e /usr/bin/fuse-overlays -a "$BUILDAH_ISOLATION" = "rootless"; then
+ if test \! -e /usr/bin/fuse-overlayfs -a "$BUILDAH_ISOLATION" = "rootless"; then
skip "BUILDAH_ISOLATION = $BUILDAH_ISOLATION" and no /usr/bin/fuse-overlayfs present
fi
image=alpine
mkdir ${TESTDIR}/lower
touch ${TESTDIR}/lower/foo
-cid=$(buildah --log-level=error from -v ${TESTDIR}/lower:/lower:O --quiet --signature-policy ${TESTSDIR}/policy.json $image)
+ cid=$(buildah --log-level=error from -v ${TESTDIR}/lower:/lower:O --quiet --signature-policy ${TESTSDIR}/policy.json $image)
# This should succeed
run_buildah --log-level=error run $cid ls /lower/foo