Add ability to set the initial owner of a custom volume

doc/api-extensions.md

@@ -2646,3 +2646,13 @@ As part of this, the following configuration options have been added:
 ## `custom_volume_refresh_exclude_older_snapshots`
 
 This adds support for excluding source snapshots earlier than latest target snapshot.
+
+## `storage_initial_owner`
+
+This adds ability to set the initial owner of a custom volume.
+
+The following configuration options have been added:
+
+* `initial.gid`
+* `initial.mode`
+* `initial.uid`

doc/reference/storage_btrfs.md

@@ -72,6 +72,9 @@ Key                             | Type      | Default                    | Descr
 
 Key                     | Type      | Condition                 | Default                                       | Description
 :--                     | :---      | :--------                 | :------                                       | :----------
+`initial.gid`           | int       | custom volume with content type `filesystem`  | same as `volume.initial.uid` or `0`           | GID of the volume owner in the instance
+`initial.mode`          | int       | custom volume with content type `filesystem`  | same as `volume.initial.mode` or `711`        | Mode  of the volume in the instance
+`initial.uid`           | int       | custom volume with content type `filesystem`  | same as `volume.initial.gid` or `0`           | UID of the volume owner in the instance
 `security.shared`       | bool      | custom block volume       | same as `volume.security.shared` or `false`   | Enable sharing the volume across multiple instances
 `security.shifted`      | bool      | custom volume             | same as `volume.security.shifted` or `false`  | {{enable_ID_shifting}}
 `security.unmapped`     | bool      | custom volume             | same as `volume.security.unmapped` or `false` | Disable ID mapping for the volume

doc/reference/storage_ceph.md

@@ -100,6 +100,9 @@ Key                     | Type      | Condition                 | Default
 :--                     | :---      | :--------                 | :------                                        | :----------
 `block.filesystem`      | string    | block-based volume with content type `filesystem` | same as `volume.block.filesystem`              | {{block_filesystem}}
 `block.mount_options`   | string    | block-based volume with content type `filesystem` | same as `volume.block.mount_options`           | Mount options for block-backed file system volumes
+`initial.gid`           | int       | custom volume with content type `filesystem`  | same as `volume.initial.uid` or `0`           | GID of the volume owner in the instance
+`initial.mode`          | int       | custom volume with content type `filesystem`  | same as `volume.initial.mode` or `711`        | Mode  of the volume in the instance
+`initial.uid`           | int       | custom volume with content type `filesystem`  | same as `volume.initial.gid` or `0`           | UID of the volume owner in the instance
 `security.shared`       | bool      | custom block volume       | same as `volume.security.shared` or `false`    | Enable sharing the volume across multiple instances
 `security.shifted`      | bool      | custom volume             | same as `volume.security.shifted` or `false`   | {{enable_ID_shifting}}
 `security.unmapped`     | bool      | custom volume             | same as `volume.security.unmapped` or `false`  | Disable ID mapping for the volume

doc/reference/storage_cephfs.md

@@ -77,6 +77,9 @@ Key                           | Type                          | Default
 
 Key                     | Type      | Condition                 | Default                                        | Description
 :--                     | :---      | :--------                 | :------                                        | :----------
+`initial.gid`           | int       | custom volume with content type `filesystem`  | same as `volume.initial.uid` or `0`           | GID of the volume owner in the instance
+`initial.mode`          | int       | custom volume with content type `filesystem`  | same as `volume.initial.mode` or `711`        | Mode  of the volume in the instance
+`initial.uid`           | int       | custom volume with content type `filesystem`  | same as `volume.initial.gid` or `0`           | UID of the volume owner in the instance
 `security.shared`       | bool      | custom block volume       | same as `volume.security.shared` or `false`    | Enable sharing the volume across multiple instances
 `security.shifted`      | bool      | custom volume             | same as `volume.security.shifted` or `false`   | {{enable_ID_shifting}}
 `security.unmapped`     | bool      | custom volume             | same as `volume.security.unmapped` or `false`  | Disable ID mapping for the volume

doc/reference/storage_dir.md

@@ -37,6 +37,9 @@ Key                           | Type                          | Default
 
 Key                     | Type      | Condition                 | Default                                        | Description
 :--                     | :---      | :--------                 | :------                                        | :----------
+`initial.gid`           | int       | custom volume with content type `filesystem`  | same as `volume.initial.uid` or `0`           | GID of the volume owner in the instance
+`initial.mode`          | int       | custom volume with content type `filesystem`  | same as `volume.initial.mode` or `711`        | Mode  of the volume in the instance
+`initial.uid`           | int       | custom volume with content type `filesystem`  | same as `volume.initial.gid` or `0`           | UID of the volume owner in the instance
 `security.shared`       | bool      | custom block volume       | same as `volume.security.shared` or `false`    | Enable sharing the volume across multiple instances
 `security.shifted`      | bool      | custom volume             | same as `volume.security.shifted` or `false`   | {{enable_ID_shifting}}
 `security.unmapped`     | bool      | custom volume             | same as `volume.security.unmapped` or `false`  | Disable ID mapping for the volume

doc/reference/storage_lvm.md

@@ -85,6 +85,9 @@ Key                   | Type   | Condition
 :--                   | :---   | :------                                           | :------                                        | :----------
 `block.filesystem`    | string | block-based volume with content type `filesystem` | same as `volume.block.filesystem`              | {{block_filesystem}}
 `block.mount_options` | string | block-based volume with content type `filesystem` | same as `volume.block.mount_options`           | Mount options for block-backed file system volumes
+`initial.gid`           | int       | custom volume with content type `filesystem`  | same as `volume.initial.uid` or `0`           | GID of the volume owner in the instance
+`initial.mode`          | int       | custom volume with content type `filesystem`  | same as `volume.initial.mode` or `711`        | Mode  of the volume in the instance
+`initial.uid`           | int       | custom volume with content type `filesystem`  | same as `volume.initial.gid` or `0`           | UID of the volume owner in the instance
 `lvm.stripes`         | string |                                                   | same as `volume.lvm.stripes`                   | Number of stripes to use for new volumes (or thin pool volume)
 `lvm.stripes.size`    | string |                                                   | same as `volume.lvm.stripes.size`              | Size of stripes to use (at least 4096 bytes and multiple of 512 bytes)
 `security.shifted`    | bool   | custom volume                                     | same as `volume.security.shifted` or `false`   | {{enable_ID_shifting}}

doc/reference/storage_zfs.md

@@ -109,6 +109,9 @@ Key                     | Type      | Condition                 | Default
 :--                     | :---      | :--------                 | :------                                        | :----------
 `block.filesystem`      | string    | block-based volume with content type `filesystem` (`zfs.block_mode` enabled) | same as `volume.block.filesystem`              | {{block_filesystem}}
 `block.mount_options`   | string    | block-based volume with content type `filesystem` (`zfs.block_mode` enabled) | same as `volume.block.mount_options`           | Mount options for block-backed file system volumes
+`initial.gid`           | int       | custom volume with content type `filesystem`  | same as `volume.initial.uid` or `0`           | GID of the volume owner in the instance
+`initial.mode`          | int       | custom volume with content type `filesystem`  | same as `volume.initial.mode` or `711`        | Mode  of the volume in the instance
+`initial.uid`           | int       | custom volume with content type `filesystem`  | same as `volume.initial.gid` or `0`           | UID of the volume owner in the instance
 `security.shared`       | bool      | custom block volume       | same as `volume.security.shared` or `false`    | Enable sharing the volume across multiple instances
 `security.shifted`      | bool      | custom volume             | same as `volume.security.shifted` or `false`   | {{enable_ID_shifting}}
 `security.unmapped`     | bool      | custom volume             | same as `volume.security.unmapped` or `false`  | Disable ID mapping for the volume

internal/server/storage/drivers/volume.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"os"
 	"slices"
+	"strconv"
 	"strings"
 
 	internalInstance "github.com/lxc/incus/v6/internal/instance"
@@ -233,8 +234,46 @@ func (v Volume) EnsureMountPath() error {
 		revert.Add(func() { _ = os.Remove(volPath) })
 	}
 
-	// Set very restrictive mode 0100 for non-custom, non-bucket and non-image volumes.
 	mode := os.FileMode(0711)
+	if v.volType == VolumeTypeCustom && v.contentType == ContentTypeFS {
+		initialMode := v.ExpandedConfig("initial.mode")
+		if initialMode != "" {
+			m, err := strconv.ParseInt(initialMode, 8, 0)
+			if err != nil {
+				return err
+			}
+
+			mode = os.FileMode(m)
+		}
+
+		uid, gid := 0, 0
+		var err error
+		initialUID := v.ExpandedConfig("initial.uid")
+		if initialUID != "" {
+			uid, err = strconv.Atoi(initialUID)
+			if err != nil {
+				return err
+			}
+		}
+
+		initialGID := v.ExpandedConfig("initial.gid")
+		if initialGID != "" {
+			gid, err = strconv.Atoi(initialGID)
+			if err != nil {
+				return err
+			}
+		}
+
+		// Set the owner of a custom volume if uid or gid have been set.
+		if uid != 0 || gid != 0 {
+			err = os.Chown(volPath, uid, gid)
+			if err != nil {
+				return err
+			}
+		}
+	}
+
+	// Set very restrictive mode 0100 for non-custom, non-bucket and non-image volumes.
 	if v.volType != VolumeTypeCustom && v.volType != VolumeTypeImage && v.volType != VolumeTypeBucket {
 		mode = os.FileMode(0100)
 	}

internal/server/storage/utils.go

@@ -491,10 +491,13 @@ func poolAndVolumeCommonRules(vol *drivers.Volume) map[string]func(string) error
 		"snapshots.pattern":  validate.IsAny,
 	}
 
-	// security.shifted and security.unmapped are only relevant for custom filesystem volumes.
+	// Options relevant for custom filesystem volumes.
 	if (vol == nil) || (vol != nil && vol.Type() == drivers.VolumeTypeCustom && vol.ContentType() == drivers.ContentTypeFS) {
 		rules["security.shifted"] = validate.Optional(validate.IsBool)
 		rules["security.unmapped"] = validate.Optional(validate.IsBool)
+		rules["initial.uid"] = validate.Optional(validate.IsInt64)
+		rules["initial.gid"] = validate.Optional(validate.IsInt64)
+		rules["initial.mode"] = validate.Optional(validate.IsInt64)
 	}
 
 	// security.shared is only relevant for custom block volumes.

internal/version/api.go

@@ -450,6 +450,7 @@ var APIExtensions = []string{
 	"instances_scriptlet_get_instances_count",
 	"cluster_rebalance",
 	"custom_volume_refresh_exclude_older_snapshots",
+	"storage_initial_owner",
 }
 
 // APIExtensionsCount returns the number of available API extensions.

test/suites/storage_volume_initial_config.sh

@@ -138,6 +138,28 @@ test_storage_volume_initial_config() {
     incus delete c --force
   fi
 
+  # Test initial owner of a custom volume configuration options.
+  incus storage volume create "${pool}" testvolume1
+  incus storage volume create "${pool}" testvolume2 initial.uid=101 initial.gid=101 initial.mode=0700
+
+  incus launch testimage c
+
+  incus storage volume attach "${pool}" testvolume1 c /testvolume1
+  incus storage volume attach "${pool}" testvolume2 c /testvolume2
+
+  [ "$(incus exec c -- stat -c %u:%g /testvolume1 )" = "0:0" ]
+  [ "$(incus exec c -- stat -c %a /testvolume1 )" = "711" ]
+  [ "$(incus exec c -- stat -c %u:%g /testvolume2 )" = "101:101" ]
+  [ "$(incus exec c -- stat -c %a /testvolume2 )" = "700" ]
+
+  incus storage volume detach "${pool}" testvolume1 c
+  incus storage volume detach "${pool}" testvolume2 c
+
+  incus delete c --force
+
+  incus storage volume delete "${pool}" testvolume1
+  incus storage volume delete "${pool}" testvolume2
+
   # Cleanup
   incus profile delete "${profile}"