From b6106341fb3a749ec37e59ee3290257a1729def1 Mon Sep 17 00:00:00 2001 From: Matthew Heon Date: Fri, 6 Sep 2019 13:52:13 -0400 Subject: When first mounting any named volume, copy up Previously, we only did this for volumes created at the same time as the container. However, this is not correct behavior - Docker does so for all named volumes, even those made with 'podman volume create' and mounted into a container later. Fixes #3945 Signed-off-by: Matthew Heon --- libpod/container_internal.go | 100 +++++++++++++++++++++++++------------ libpod/container_internal_linux.go | 4 +- libpod/runtime_ctr.go | 4 -- libpod/volume.go | 7 +++ libpod/volume_internal.go | 2 + test/e2e/run_volume_test.go | 21 ++++++++ 6 files changed, 101 insertions(+), 37 deletions(-) diff --git a/libpod/container_internal.go b/libpod/container_internal.go index ffc6c11ee..78305d761 100644 --- a/libpod/container_internal.go +++ b/libpod/container_internal.go @@ -21,6 +21,7 @@ import ( "github.com/containers/storage" "github.com/containers/storage/pkg/archive" "github.com/containers/storage/pkg/mount" + "github.com/cyphar/filepath-securejoin" spec "github.com/opencontainers/runtime-spec/specs-go" "github.com/opencontainers/runtime-tools/generate" "github.com/opencontainers/selinux/go-selinux/label" @@ -1234,43 +1235,82 @@ func (c *Container) mountStorage() (_ string, Err error) { }() } + // We need to mount the container before volumes - to ensure the copyup + // works properly. + mountPoint := c.config.Rootfs + if mountPoint == "" { + mountPoint, err = c.mount() + if err != nil { + return "", err + } + defer func() { + if Err != nil { + if err := c.unmount(false); err != nil { + logrus.Errorf("Error unmounting container %s after mount error: %v", c.ID(), err) + } + } + }() + } + // Request a mount of all named volumes for _, v := range c.config.NamedVolumes { - vol, err := c.runtime.state.Volume(v.Name) + vol, err := c.mountNamedVolume(v, mountPoint) if err != nil { - return "", errors.Wrapf(err, "error retrieving named volume %s for container %s", v.Name, c.ID()) + return "", err } - - if vol.needsMount() { + defer func() { + if Err == nil { + return + } vol.lock.Lock() - if err := vol.mount(); err != nil { - vol.lock.Unlock() - return "", errors.Wrapf(err, "error mounting volume %s for container %s", vol.Name(), c.ID()) + if err := vol.unmount(false); err != nil { + logrus.Errorf("Error unmounting volume %s after error mounting container %s: %v", vol.Name(), c.ID(), err) } vol.lock.Unlock() - defer func() { - if Err == nil { - return - } - vol.lock.Lock() - if err := vol.unmount(false); err != nil { - logrus.Errorf("Error unmounting volume %s after error mounting container %s: %v", vol.Name(), c.ID(), err) - } - vol.lock.Unlock() - }() - } + }() } - // TODO: generalize this mount code so it will mount every mount in ctr.config.Mounts - mountPoint := c.config.Rootfs - if mountPoint == "" { - mountPoint, err = c.mount() - if err != nil { - return "", err + return mountPoint, nil +} + +// Mount a single named volume into the container. +// If necessary, copy up image contents into the volume. +// Does not verify that the name volume given is actually present in container +// config. +// Returns the volume that was mounted. +func (c *Container) mountNamedVolume(v *ContainerNamedVolume, mountpoint string) (*Volume, error) { + vol, err := c.runtime.state.Volume(v.Name) + if err != nil { + return nil, errors.Wrapf(err, "error retrieving named volume %s for container %s", v.Name, c.ID()) + } + + vol.lock.Lock() + defer vol.lock.Unlock() + if vol.needsMount() { + if err := vol.mount(); err != nil { + return nil, errors.Wrapf(err, "error mounting volume %s for container %s", vol.Name(), c.ID()) } } + // The volume may need a copy-up. Check the state. + if err := vol.update(); err != nil { + return nil, err + } + if vol.state.NeedsCopyUp { + logrus.Debugf("Copying up contents from container %s to volume %s", c.ID(), vol.Name()) + srcDir, err := securejoin.SecureJoin(mountpoint, v.Dest) + if err != nil { + return nil, errors.Wrapf(err, "error calculating destination path to copy up container %s volume %s", c.ID(), vol.Name()) + } + if err := c.copyWithTarFromImage(srcDir, vol.MountPoint()); err != nil && !os.IsNotExist(err) { + return nil, errors.Wrapf(err, "error copying content from container %s into volume %s", c.ID(), vol.Name()) + } - return mountPoint, nil + vol.state.NeedsCopyUp = false + if err := vol.save(); err != nil { + return nil, err + } + } + return vol, nil } // cleanupStorage unmounts and cleans up the container's root filesystem @@ -1614,15 +1654,11 @@ func (c *Container) unmount(force bool) error { } // this should be from chrootarchive. -func (c *Container) copyWithTarFromImage(src, dest string) error { - mountpoint, err := c.mount() - if err != nil { - return err - } +// Container MUST be mounted before calling. +func (c *Container) copyWithTarFromImage(source, dest string) error { a := archive.NewDefaultArchiver() - source := filepath.Join(mountpoint, src) - if err = c.copyOwnerAndPerms(source, dest); err != nil { + if err := c.copyOwnerAndPerms(source, dest); err != nil { return err } return a.CopyWithTar(source, dest) diff --git a/libpod/container_internal_linux.go b/libpod/container_internal_linux.go index e96af8536..03374a060 100644 --- a/libpod/container_internal_linux.go +++ b/libpod/container_internal_linux.go @@ -115,7 +115,9 @@ func (c *Container) prepare() (Err error) { createErr = createNetNSErr } if mountStorageErr != nil { - logrus.Errorf("Error preparing container %s: %v", c.ID(), createErr) + if createErr != nil { + logrus.Errorf("Error preparing container %s: %v", c.ID(), createErr) + } createErr = mountStorageErr } diff --git a/libpod/runtime_ctr.go b/libpod/runtime_ctr.go index acd317d20..0b4fbda7a 100644 --- a/libpod/runtime_ctr.go +++ b/libpod/runtime_ctr.go @@ -275,10 +275,6 @@ func (r *Runtime) setupContainer(ctx context.Context, ctr *Container) (c *Contai return nil, errors.Wrapf(err, "error creating named volume %q", vol.Name) } - if err := ctr.copyWithTarFromImage(vol.Dest, newVol.MountPoint()); err != nil && !os.IsNotExist(err) { - return nil, errors.Wrapf(err, "Failed to copy content into new volume mount %q", vol.Name) - } - ctrNamedVolumes = append(ctrNamedVolumes, newVol) } diff --git a/libpod/volume.go b/libpod/volume.go index b4de3aedc..c4771bbb8 100644 --- a/libpod/volume.go +++ b/libpod/volume.go @@ -57,6 +57,13 @@ type VolumeState struct { // On incrementing from 0, the volume will be mounted on the host. // On decrementing to 0, the volume will be unmounted on the host. MountCount uint `json:"mountCount"` + // NeedsCopyUp indicates that the next time the volume is mounted into + // a container, the container will "copy up" the contents of the + // mountpoint into the volume. + // This should only be done once. As such, this is set at container + // create time, then cleared after the copy up is done and never set + // again. + NeedsCopyUp bool `json:"notYetMounted,omitempty"` } // Name retrieves the volume's name diff --git a/libpod/volume_internal.go b/libpod/volume_internal.go index 2e886e1b0..42b935e7c 100644 --- a/libpod/volume_internal.go +++ b/libpod/volume_internal.go @@ -11,9 +11,11 @@ import ( func newVolume(runtime *Runtime) (*Volume, error) { volume := new(Volume) volume.config = new(VolumeConfig) + volume.state = new(VolumeState) volume.runtime = runtime volume.config.Labels = make(map[string]string) volume.config.Options = make(map[string]string) + volume.state.NeedsCopyUp = true return volume, nil } diff --git a/test/e2e/run_volume_test.go b/test/e2e/run_volume_test.go index 551e86b93..fc1998ab2 100644 --- a/test/e2e/run_volume_test.go +++ b/test/e2e/run_volume_test.go @@ -249,4 +249,25 @@ var _ = Describe("Podman run with volumes", func() { fmt.Printf("Output: %s", mountOut3) Expect(strings.Contains(mountOut3, volName)).To(BeFalse()) }) + + It("podman named volume copyup", func() { + baselineSession := podmanTest.Podman([]string{"run", "--rm", "-t", "-i", ALPINE, "ls", "/etc/apk/"}) + baselineSession.WaitWithDefaultTimeout() + Expect(baselineSession.ExitCode()).To(Equal(0)) + baselineOutput := baselineSession.OutputToString() + + inlineVolumeSession := podmanTest.Podman([]string{"run", "--rm", "-t", "-i", "-v", "testvol1:/etc/apk", ALPINE, "ls", "/etc/apk/"}) + inlineVolumeSession.WaitWithDefaultTimeout() + Expect(inlineVolumeSession.ExitCode()).To(Equal(0)) + Expect(inlineVolumeSession.OutputToString()).To(Equal(baselineOutput)) + + makeVolumeSession := podmanTest.Podman([]string{"volume", "create", "testvol2"}) + makeVolumeSession.WaitWithDefaultTimeout() + Expect(makeVolumeSession.ExitCode()).To(Equal(0)) + + separateVolumeSession := podmanTest.Podman([]string{"run", "--rm", "-t", "-i", "-v", "testvol2:/etc/apk", ALPINE, "ls", "/etc/apk/"}) + separateVolumeSession.WaitWithDefaultTimeout() + Expect(separateVolumeSession.ExitCode()).To(Equal(0)) + Expect(separateVolumeSession.OutputToString()).To(Equal(baselineOutput)) + }) }) -- cgit v1.2.3-54-g00ecf