particle-os/debian-forge-cli
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

setup: Simplify container-storage mounted check

Browse source 
I ran into the `--local` option not working at least in my
setup with the current container image (which for some reason
hasn't been updated, and predates the latest tip commit
which talks about btrfs)

On this current test system (MacOS + podman 5 + default podman-machine)
things do work with the tip commit.

However...I don't quite understand the need to *both* try to
run `systemd-detect-virt` *and* parse `/proc/self/mountinfo`.

(BTW, the logic for `insideContainer` was really confusing me because
 it only returned `true` if we were *not* in a container...I wonder
 if that was really intentional?)

Anyways, I think the goal here is just a friendly direct error
message if it doesn't look like the mount is there, which we can
do by just checking for the file path.  If it isn't mounted
from the host then nothing will be there.

Signed-off-by: Colin Walters <walters@verbum.org>
This commit is contained in:
Colin Walters 2024-04-01 14:30:37 -04:00 • committed by Simon de Vlieger
parent 2f0d81288a
commit 9b280f0ba3
3 changed files with 11 additions and 147 deletions
Download patch file Download diff file Expand all files Collapse all files

13
bib/internal/setup/export_test.go
View file

@ -1,13 +0,0 @@
package setup
var (
ValidateHasContainerStorageMountedFromReader = validateHasContainerStorageMountedFromReader
)
func MockInsideContainer(f func() (bool, error)) (restore func()) {
saved := insideContainer
insideContainer = f
return func() {
insideContainer = saved
}
}

66
bib/internal/setup/setup.go
View file

@ -2,13 +2,9 @@ package setup
import ( import (
"fmt" "fmt"
"io"
"os" "os"
"os/exec"
"path/filepath" "path/filepath"
"strings"
"github.com/moby/sys/mountinfo"
"golang.org/x/sys/unix" "golang.org/x/sys/unix"
"github.com/osbuild/bootc-image-builder/bib/internal/podmanutil" "github.com/osbuild/bootc-image-builder/bib/internal/podmanutil"
@ -102,60 +98,20 @@ func Validate() error {
return nil return nil
} }
var insideContainer = func() (bool, error) { // ValidateHasContainerStorageMounted checks that the hostcontainer storage
if err := exec.Command("systemd-detect-virt", "-c").Run(); err != nil {
if exitErr, ok := err.(*exec.ExitError); ok {
// not running in a container, just exit
if exitErr.ExitCode() == 1 {
return true, nil
}
}
return false, err
}
return false, nil
}
// ValidateHasContainerStorageMounted checks that the container storage
// is mounted inside the container // is mounted inside the container
func ValidateHasContainerStorageMounted() error { func ValidateHasContainerStorageMounted() error {
inside, err := insideContainer() // Just look for the overlay backend, which we expect by default.
if err != nil { // In theory, one could be using a different backend, but we don't
return err // really need to worry about this right now. If it turns out
} // we do need to care, then we can probably handle this by
if inside { // just trying to query the image.
return nil overlayPath := "/var/lib/containers/storage/overlay"
} if _, err := os.Stat(overlayPath); err != nil {
if os.IsNotExist(err) {
f, err := os.Open("/proc/self/mountinfo") return fmt.Errorf("cannot find %q (missing -v /var/lib/containers/storage:/var/lib/containers/storage mount?)", overlayPath)
if err != nil {
return err
}
defer f.Close()
return validateHasContainerStorageMountedFromReader(f)
}
func validateHasContainerStorageMountedFromReader(r io.Reader) error {
containersStorage := "/var/lib/containers/storage"
containerStorageMountFound := false
mnts, err := mountinfo.GetMountsFromReader(r, nil)
if err != nil {
return err
}
for _, mnt := range mnts {
if mnt.Mountpoint != containersStorage {
continue
}
containerStorageMountFound = true
// on btrfs the containers storage might be on a subvolume
// so we just compare the final part of the path
if !strings.HasSuffix(mnt.Root, containersStorage) {
return fmt.Errorf("cannot find suffix %q in mounted %q", containersStorage, mnt.Root)
} }
return fmt.Errorf("failed to stat %q: %w", overlayPath, err)
} }
if !containerStorageMountFound {
return fmt.Errorf("cannot find mount for %q", containersStorage)
}
return nil return nil
} }

79
bib/internal/setup/setup_test.go
View file

@ -1,79 +0,0 @@
package setup_test
import (
"bytes"
"testing"
"github.com/stretchr/testify/assert"
"github.com/osbuild/bootc-image-builder/bib/internal/setup"
)
var (
procSelfMountinfoBtrfs = `1345 1307 0:92 / / rw,relatime - overlay overlay rw,context="system_u:object_r:container_file_t:s0:c98,c684",lowerdir=/var/lib/containers/storage/overlay/l/T4G5ED56VRUEC2ID7JMJSGW3QT:/var/lib/containers/storage/overlay/l/KZGLWVLLUSCKZYWV57JF6WSK2I:/var/lib/containers/storage/overlay/l/HXWMTP6IYXVK4KUZ2UCSNJXOIW:/var/lib/containers/storage/overlay/l/YLBHA4OHH25PNVUIUV7LKJA67Q:/var/lib/containers/storage/overlay/l/7IH6AODKJYPJSHYY3KTKRAGDZO:/var/lib/containers/storage/overlay/l/EELW6SDH3FRQMJJEGMTWJ223DL:/var/lib/containers/storage/overlay/l/GNKPUG6OGVJANN4MB447IM4JK7,upperdir=/var/lib/containers/storage/overlay/f2d065994b6e5d208732fc71a7421f882a6b2f73809bcc210a00d4c49309c10f/diff,workdir=/var/lib/containers/storage/overlay/f2d065994b6e5d208732fc71a7421f882a6b2f73809bcc210a00d4c49309c10f/work,redirect_dir=on,uuid=on,metacopy=on,volatile
1346 1345 0:96 / /sys rw,nosuid,nodev,noexec,relatime - sysfs sysfs rw,seclabel
1348 1345 0:97 / /proc rw,nosuid,nodev,noexec,relatime - proc proc rw
1349 1345 0:99 / /dev rw,nosuid - tmpfs tmpfs rw,context="system_u:object_r:container_file_t:s0:c98,c684",size=65536k,mode=755,inode64
1352 1349 0:100 / /dev/pts rw,nosuid,noexec,relatime - devpts devpts rw,context="system_u:object_r:container_file_t:s0:c98,c684",gid=5,mode=620,ptmxmode=666
1361 1349 0:85 / /dev/shm rw,nosuid,nodev,noexec,relatime - tmpfs shm rw,context="system_u:object_r:container_file_t:s0:c98,c684",size=64000k,inode64
1363 1346 0:27 / /sys/fs/cgroup rw,nosuid,nodev,noexec,relatime - cgroup2 cgroup2 rw,seclabel,nsdelegate,memory_recursiveprot
1364 1345 0:33 /root/var/lib/containers/storage /var/lib/containers/storage rw,relatime - btrfs /dev/mapper/luks-12345678-1234-1234-1234-123456789012 rw,seclabel,compress=zstd:1,ssd,discard=async,space_cache,subvolid=257,subvol=/root
1365 1364 0:33 /root/var/lib/containers/storage/overlay /var/lib/containers/storage/overlay rw,relatime - btrfs /dev/mapper/luks-12345678-1234-1234-1234-123456789012 rw,seclabel,compress=zstd:1,ssd,discard=async,space_cache,subvolid=257,subvol=/root
`
procSelfMountinfoWithVolume = `735 665 0:83 / / rw,relatime - overlay overlay rw,lowerdir=/var/lib/containers/storage/overlay/l/2BFF257G6Q5T5OWGW4JVUDTM3R:/var/lib/containers/storage/overlay/l/AEC37A7HVU4SH5Q4GWQLB7KCZU:/var/lib/containers/storage/overlay/l/JFOUQY5ZWN3DIZQP22SYYLXEV7,upperdir=/var/lib/containers/storage/overlay/d545c8ca670b6820eae79e43836175558d71f9f927fb68feffa608a2b3020f09/diff,workdir=/var/lib/containers/storage/overlay/d545c8ca670b6820eae79e43836175558d71f9f927fb68feffa608a2b3020f09/work,uuid=on,volatile
736 735 259:2 /var/lib/containers/storage/volumes/e14ef96e3db8bdc3dcdbd340208995e6770cd7873f78788e737c8b7b5d17fdaa/_data /output rw,nosuid,nodev,relatime - ext4 /dev/nvme0n1p2 rw,errors=remount-ro
737 735 0:86 / /proc rw,nosuid,nodev,noexec,relatime - proc proc rw
738 735 0:87 / /dev rw,nosuid - tmpfs tmpfs rw,size=65536k,mode=755,inode64
741 735 0:88 / /sys rw,nosuid,nodev,noexec,relatime - sysfs sysfs rw
742 738 0:89 / /dev/pts rw,nosuid,noexec,relatime - devpts devpts rw,gid=5,mode=620,ptmxmode=666
743 738 0:85 / /dev/mqueue rw,nosuid,nodev,noexec,relatime - mqueue mqueue rw
744 735 0:24 /containers/storage/overlay-containers/5e5914d9351994648b28b8b58ba3c67ce06a48ccdd3a52679b82ae4dc693fa53/userdata/.containerenv /run/.containerenv rw,relatime - tmpfs tmpfs rw,size=3262508k,mode=755,inode64
745 735 0:24 /containers/storage/overlay-containers/5e5914d9351994648b28b8b58ba3c67ce06a48ccdd3a52679b82ae4dc693fa53/userdata/hostname /etc/hostname rw,relatime - tmpfs tmpfs rw,size=3262508k,mode=755,inode64
746 735 0:24 /containers/storage/overlay-containers/5e5914d9351994648b28b8b58ba3c67ce06a48ccdd3a52679b82ae4dc693fa53/userdata/resolv.conf /etc/resolv.conf rw,relatime - tmpfs tmpfs rw,size=3262508k,mode=755,inode64
747 735 0:24 /containers/storage/overlay-containers/5e5914d9351994648b28b8b58ba3c67ce06a48ccdd3a52679b82ae4dc693fa53/userdata/hosts /etc/hosts rw,relatime - tmpfs tmpfs rw,size=3262508k,mode=755,inode64
748 738 0:82 / /dev/shm rw,nosuid,nodev,noexec,relatime - tmpfs shm rw,size=64000k,inode64
749 741 0:28 / /sys/fs/cgroup rw,nosuid,nodev,noexec,relatime - cgroup2 cgroup2 rw,nsdelegate,memory_recursiveprot
750 735 259:2 /var/lib/containers/storage /var/lib/containers/storage rw,relatime - ext4 /dev/nvme0n1p2 rw,errors=remount-ro
751 750 259:2 /var/lib/containers/storage/overlay /var/lib/containers/storage/overlay rw,relatime - ext4 /dev/nvme0n1p2 rw,errors=remount-ro
`
procSelfMountinfoNoVolume = `736 735 259:2 /var/lib/containers/storage/volumes/5c45612492556520d9549b3ee24d6a11ac3a0e9266c0900bf427a3bdaafadeb8/_data /rpmmd rw,nosuid,nodev,relatime - ext4 /dev/nvme0n1p2 rw,errors=remount-ro
737 735 259:2 /var/lib/containers/storage/volumes/e17849f054757adebabc844a1fd510308a1c22b6668526e84511a8dfd617aec8/_data /output rw,nosuid,nodev,relatime - ext4 /dev/nvme0n1p2 rw,errors=remount-ro
738 735 0:86 / /proc rw,nosuid,nodev,noexec,relatime - proc proc rw
739 735 259:2 /var/lib/containers/storage/volumes/8b15ab68602eaee4923cfddd7c0cbb19d7d33190c9d2f97adeea357370f5ba3b/_data /store rw,nosuid,nodev,relatime - ext4 /dev/nvme0n1p2 rw,errors=remount-ro
740 735 0:87 / /sys rw,nosuid,nodev,noexec,relatime - sysfs sysfs rw
741 735 0:88 / /dev rw,nosuid - tmpfs tmpfs rw,size=65536k,mode=755,inode64
742 741 0:85 / /dev/mqueue rw,nosuid,nodev,noexec,relatime - mqueue mqueue rw
743 741 0:89 / /dev/pts rw,nosuid,noexec,relatime - devpts devpts rw,gid=5,mode=620,ptmxmode=666
745 741 0:82 / /dev/shm rw,nosuid,nodev,noexec,relatime - tmpfs shm rw,size=64000k,inode64
750 735 259:2 /var/lib/containers/storage/volumes/8612bf74115e4610cf4a57da8a0209fa07d1782584752bf4a1991d773f9c608f/_data /var/lib/containers/storage rw,nosuid,nodev,relatime - ext4 /dev/nvme0n1p2 rw,errors=remount-ro
666 741 0:89 /0 /dev/console rw,relatime - devpts devpts rw,gid=5,mode=620,ptmxmode=666
`
)
func TestValidateHasContainerStorageMountedBtrfs(t *testing.T) {
restore := setup.MockInsideContainer(func() (bool, error) {
return true, nil
})
defer restore()
for _, tc := range []struct {
fakeMountinfo string
expectedErr string
}{
// good
{procSelfMountinfoBtrfs, ""},
{procSelfMountinfoWithVolume, ""},
// bad
{procSelfMountinfoNoVolume, `cannot find suffix "/var/lib/containers/storage" in mounted "/var/lib/containers/storage/volumes/8612bf74115e4610cf4a57da8a0209fa07d1782584752bf4a1991d773f9c608f/_data"`},
} {
buf := bytes.NewBufferString(tc.fakeMountinfo)
err := setup.ValidateHasContainerStorageMountedFromReader(buf)
if tc.expectedErr == "" {
assert.NoError(t, err)
} else {
assert.Error(t, err)
assert.Equal(t, tc.expectedErr, err.Error())
}
}
}