Command `podman system df` returns a negative reclaimable size of images

### Issue Description

Command `podman system df` returns a negative reclaimable size of images.

```
[web@s4 ~]$ podman system df
TYPE           TOTAL       ACTIVE      SIZE        RECLAIMABLE
Images         8           6           1.311GB     -5.989e+08B (-46%)
Containers     15          15          196.2kB     0B (0%)
Local Volumes  0           0           0B          0B (0%)
```

It happens after I run 2 containers based on custom images with a common ancestor image, and then run `podman image prune -a`.

### Steps to reproduce the issue

```bash
# Start from clean Alma Linux 9.
sudo -i
dnf update
dnf install podman

podman --version
#podman version 4.9.4-rhel

mkdir test12 test13

for t in test12 test13; do
  cat <<EOF >"${t}/Dockerfile"
FROM docker.io/library/busybox:latest
RUN echo "${t}" >${t}.txt
CMD ["sh", "-c", "while true; do cat ${t}.txt; sleep 5; done"]
EOF
  podman build --tag "${t}:latest" "${t}"
  podman run -d "${t}"
done

podman system df
#TYPE           TOTAL       ACTIVE      SIZE        RECLAIMABLE
#Images         5           2           4.539MB     4.538MB (100%)
#Containers     2           2           22.68kB     0B (0%)
#Local Volumes  0           0           0B          0B (0%)

podman image prune -a
#WARNING! This command removes all images without at least one container associated with them.
#Are you sure you want to continue? [y/N] y
#27a71e19c95622dce4d60d4a3760707495c9875f5c5322c5bd535214799593ce
#ff85c5105a9ccd2209e7892bc827377002769cf5f8578ebb45672a5cb166a643
#ae7c431f01c373313df85b278eda9a7c068e909737d113da37d91158ab80e193

podman system df
#TYPE           TOTAL       ACTIVE      SIZE        RECLAIMABLE
#Images         2           2           4.522MB     -4.506e+06B (-100%)
#Containers     2           2           22.68kB     0B (0%)
#Local Volumes  0           0           0B          0B (0%)
```

<details>
<summary>My original steps</summary>

`php-base` is a custom image based on PHP. 
`mybb-custom` and `grav-custom` are custom images based on `php-base`.

```
[web@s4 ~]$ podman images
REPOSITORY                 TAG                    IMAGE ID      CREATED       SIZE
localhost/podman-pause     4.9.4-rhel-1728876463  34106bccc6d0  39 hours ago  2.44 MB
<none>                     <none>                 af1921c0516a  39 hours ago  814 kB
<none>                     <none>                 c5ffd57e0aa1  39 hours ago  814 kB
<none>                     <none>                 a8cf0a7c3e87  39 hours ago  814 kB
localhost/mybb-custom      latest                 efad2395902f  39 hours ago  521 MB
localhost/mybb-custom      2024.10.31-21.25       efad2395902f  39 hours ago  521 MB
localhost/grav-custom      latest                 a5d7ee269409  39 hours ago  521 MB
localhost/grav-custom      2024.10.31-21.25       a5d7ee269409  39 hours ago  521 MB
localhost/php-base         2024.10.31-21.23       ca6f80a64bab  39 hours ago  521 MB
localhost/php-base         latest                 ca6f80a64bab  39 hours ago  521 MB
docker.io/library/php      8.3-apache             2d9e3fa41a3c  8 days ago    514 MB
docker.io/library/nginx    1.27.2                 3b25b682ea82  4 weeks ago   196 MB
docker.io/library/adminer  4.8.1                  2f7580903a1d  3 months ago  258 MB
docker.io/library/mariadb  11.3.2                 3ba807438681  5 months ago  411 MB
```
```
[web@s4 ~]$ podman system df
TYPE           TOTAL       ACTIVE      SIZE        RECLAIMABLE
Images         19          6           1.311GB     443.5MB (34%)
Containers     15          15          196.2kB     0B (0%)
Local Volumes  0           0           0B          0B (0%)
```
```
[web@s4 ~]$ podman image prune
WARNING! This command removes all dangling images.
Are you sure you want to continue? [y/N] y
a8cf0a7c3e87fe39ef9efd94457f04e7d51bf1e9c6226c0e3ccca1b7d4e399e7
c5ffd57e0aa16a9c2908317b5e7d7dfb298926753f0935839f08d1a2ea08f3cb
af1921c0516a7121336a3cebda23b97b523da46b4f1dc7a9378432d1da7f47a3
```
```
[web@s4 ~]$ podman images
REPOSITORY                 TAG                    IMAGE ID      CREATED       SIZE
localhost/podman-pause     4.9.4-rhel-1728876463  34106bccc6d0  39 hours ago  2.44 MB
localhost/mybb-custom      latest                 efad2395902f  39 hours ago  521 MB
localhost/mybb-custom      2024.10.31-21.25       efad2395902f  39 hours ago  521 MB
localhost/php-base         latest                 ca6f80a64bab  39 hours ago  521 MB
localhost/php-base         2024.10.31-21.23       ca6f80a64bab  39 hours ago  521 MB
localhost/grav-custom      latest                 a5d7ee269409  39 hours ago  521 MB
localhost/grav-custom      2024.10.31-21.25       a5d7ee269409  39 hours ago  521 MB
docker.io/library/php      8.3-apache             2d9e3fa41a3c  8 days ago    514 MB
docker.io/library/nginx    1.27.2                 3b25b682ea82  4 weeks ago   196 MB
docker.io/library/adminer  4.8.1                  2f7580903a1d  3 months ago  258 MB
docker.io/library/mariadb  11.3.2                 3ba807438681  5 months ago  411 MB
```
```
[web@s4 ~]$ podman image prune -a
WARNING! This command removes all images without at least one container associated with them.
Are you sure you want to continue? [y/N] y
2d9e3fa41a3cfb8f9870aafb92d454d7a635587b7d996df5ccaef5a4a689b122
75ec9b338c7578aa24408033f23d5d05eaf6cfab351b8dd1f729981722ead76b
5addd0593e47cf849f3ccdd663f34826c2f0bc7b9ba3d6218d7e54783ba9bdee
2e4196b3bc785975d94dd76633d3ef675644c6f9b0623eeed4351aae98660121
d500fa13d993843f8049df0ea6b2b76c6b6d3889c549def3790ede174bfda453
ba2136c5cd622a42ee3b142b4bdee3e577bae40aaf5795048691b9b2887c1f06
ca6f80a64bab731ed6e944d8ea7d4caa10824b81901c25572b054e86ea74a97a
```
```
[web@s4 ~]$ podman images
REPOSITORY                 TAG                    IMAGE ID      CREATED       SIZE
localhost/podman-pause     4.9.4-rhel-1728876463  34106bccc6d0  39 hours ago  2.44 MB
localhost/mybb-custom      latest                 efad2395902f  39 hours ago  521 MB
localhost/mybb-custom      2024.10.31-21.25       efad2395902f  39 hours ago  521 MB
localhost/grav-custom      latest                 a5d7ee269409  39 hours ago  521 MB
localhost/grav-custom      2024.10.31-21.25       a5d7ee269409  39 hours ago  521 MB
docker.io/library/nginx    1.27.2                 3b25b682ea82  4 weeks ago   196 MB
docker.io/library/adminer  4.8.1                  2f7580903a1d  3 months ago  258 MB
docker.io/library/mariadb  11.3.2                 3ba807438681  5 months ago  411 MB
```
```
[web@s4 ~]$ podman system df
TYPE           TOTAL       ACTIVE      SIZE        RECLAIMABLE
Images         8           6           1.311GB     -5.989e+08B (-46%)
Containers     15          15          196.2kB     0B (0%)
Local Volumes  0           0           0B          0B (0%)
```
```
[web@s4 ~]$ podman --version
podman version 4.9.4-rhel
```
</details>

### Describe the results you received

Unexpected value in Images-RECLAIMABLE.
```
[web@s4 ~]$ podman system df
TYPE           TOTAL       ACTIVE      SIZE        RECLAIMABLE
Images         8           6           1.311GB     -5.989e+08B (-46%)
Containers     15          15          196.2kB     0B (0%)
Local Volumes  0           0           0B          0B (0%)
```

### Describe the results you expected

No reclaimable space after pruning.
```
[web@s4 ~]$ podman system df
TYPE           TOTAL       ACTIVE      SIZE        RECLAIMABLE
Images         8           6           1.311GB     0B (0%)
Containers     15          15          196.2kB     0B (0%)
Local Volumes  0           0           0B          0B (0%)
```

### podman info output

<details>
<summary>podman info</summary>

```
[web@s4 ~]$ podman info
host:
  arch: amd64
  buildahVersion: 1.33.8
  cgroupControllers:
  - memory
  - pids
  cgroupManager: systemd
  cgroupVersion: v2
  conmon:
    package: conmon-2.1.10-1.el9.x86_64
    path: /usr/bin/conmon
    version: 'conmon version 2.1.10, commit: 574ce145d4fde456322f648afc2cb9dc2141ee16'
  cpuUtilization:
    idlePercent: 98.34
    systemPercent: 0.85
    userPercent: 0.81
  cpus: 1
  databaseBackend: sqlite
  distribution:
    distribution: almalinux
    version: "9.4"
  eventLogger: journald
  freeLocks: 2028
  hostname: s4.lab
  idMappings:
    gidmap:
    - container_id: 0
      host_id: 993
      size: 1
    - container_id: 1
      host_id: 100000
      size: 65536
    uidmap:
    - container_id: 0
      host_id: 996
      size: 1
    - container_id: 1
      host_id: 100000
      size: 65536
  kernel: 5.14.0-427.40.1.el9_4.x86_64
  linkmode: dynamic
  logDriver: journald
  memFree: 117637120
  memTotal: 738689024
  networkBackend: netavark
  networkBackendInfo:
    backend: netavark
    dns:
      package: aardvark-dns-1.10.0-3.el9_4.x86_64
      path: /usr/libexec/podman/aardvark-dns
      version: aardvark-dns 1.10.0
    package: netavark-1.10.3-1.el9.x86_64
    path: /usr/libexec/podman/netavark
    version: netavark 1.10.3
  ociRuntime:
    name: crun
    package: crun-1.14.3-1.el9.x86_64
    path: /usr/bin/crun
    version: |-
      crun version 1.14.3
      commit: 1961d211ba98f532ea52d2e80f4c20359f241a98
      rundir: /run/user/996/crun
      spec: 1.0.0
      +SYSTEMD +SELINUX +APPARMOR +CAP +SECCOMP +EBPF +CRIU +YAJL
  os: linux
  pasta:
    executable: ""
    package: ""
    version: ""
  remoteSocket:
    exists: false
    path: /run/user/996/podman/podman.sock
  security:
    apparmorEnabled: false
    capabilities: CAP_CHOWN,CAP_DAC_OVERRIDE,CAP_FOWNER,CAP_FSETID,CAP_KILL,CAP_NET_BIND_SERVICE,CAP_SETFCAP,CAP_SETGID,CAP_SETPCAP,CAP_SETUID,CAP_SYS_CHROOT
    rootless: true
    seccompEnabled: true
    seccompProfilePath: /usr/share/containers/seccomp.json
    selinuxEnabled: true
  serviceIsRemote: false
  slirp4netns:
    executable: /bin/slirp4netns
    package: slirp4netns-1.2.3-1.el9.x86_64
    version: |-
      slirp4netns version 1.2.3
      commit: c22fde291bb35b354e6ca44d13be181c76a0a432
      libslirp: 4.4.0
      SLIRP_CONFIG_VERSION_MAX: 3
      libseccomp: 2.5.2
  swapFree: 2006286336
  swapTotal: 2151673856
  uptime: 1h 59m 18.00s (Approximately 0.04 days)
  variant: ""
plugins:
  authorization: null
  log:
  - k8s-file
  - none
  - passthrough
  - journald
  network:
  - bridge
  - macvlan
  - ipvlan
  volume:
  - local
registries:
  search:
  - registry.access.redhat.com
  - registry.redhat.io
  - docker.io
store:
  configFile: /home/web/.config/containers/storage.conf
  containerStore:
    number: 15
    paused: 0
    running: 15
    stopped: 0
  graphDriverName: overlay
  graphOptions: {}
  graphRoot: /home/web/.local/share/containers/storage
  graphRootAllocated: 23546822656
  graphRootUsed: 4689367040
  graphStatus:
    Backing Filesystem: xfs
    Native Overlay Diff: "true"
    Supports d_type: "true"
    Supports shifting: "false"
    Supports volatile: "true"
    Using metacopy: "false"
  imageCopyTmpDir: /var/tmp
  imageStore:
    number: 6
  runRoot: /run/user/996/containers
  transientStore: false
  volumePath: /home/web/.local/share/containers/storage/volumes
version:
  APIVersion: 4.9.4-rhel
  Built: 1728876463
  BuiltTime: Mon Oct 14 05:27:43 2024
  GitCommit: ""
  GoVersion: go1.21.13 (Red Hat 1.21.13-4.el9_4)
  Os: linux
  OsArch: linux/amd64
  Version: 4.9.4-rhel
```
</details>

### Podman in a container

No

### Privileged Or Rootless

Root or rootless - issue reproduced in both cases.

### Upstream Latest Release

Reproduced in both: 
* `4.9.4-rhel` latest in the Alma Linux 9 repositories
* Current `main` as of 2024-11-13

### Additional environment details

_No response_

### Additional information

_No response_

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Command `podman system df` returns a negative reclaimable size of images #24452

Issue Description

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Describe the results you received

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podman info output

Podman in a container

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Command podman system df returns a negative reclaimable size of images #24452

Description

Issue Description

Steps to reproduce the issue

Describe the results you received

Describe the results you expected

podman info output

Podman in a container

Privileged Or Rootless

Upstream Latest Release

Additional environment details

Additional information

Metadata

Metadata

Assignees

Labels

Type

Projects

Milestone

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Development

Issue actions

Command `podman system df` returns a negative reclaimable size of images #24452