fix(xo-vmdk-to-vhd): handle ova with disk position collision (#7051)

Some OVA have multiple disks with the same position, which prevent the VM from being created (error while creating VBD). Renumeroting the problematic disk works around the issue.

This may lead to unbootable VM in case the renumeroted disk was the bootable one (VMware-VirtualSAN-Witness-7.0.0-15843807.ova for example).

Fixes #7046

CHANGELOG.unreleased.md

@@ -20,6 +20,7 @@
 - [OVA Export] Fix support of disks with more than 8.2GiB of content (PR [#7047](https://github.com/vatesfr/xen-orchestra/pull/7047))
 - [Backup] Fix `VHDFile implementation is not compatible with encrypted remote` when using VHD directory with encryption (PR [#7045](https://github.com/vatesfr/xen-orchestra/pull/7045))
 - [Backup/Mirror] Fix `xo:fs:local WARN lock compromised` when mirroring a Backup Repository to a local/NFS/SMB repository ([#7043](https://github.com/vatesfr/xen-orchestra/pull/7043))
+- [Ova import] Fix importing VM with collision in disk position (PR [#7051](https://github.com/vatesfr/xen-orchestra/pull/7051)) (issue [7046](https://github.com/vatesfr/xen-orchestra/issues/7046))
 
 ### Packages to release
 
@@ -39,6 +40,7 @@
 
 - @xen-orchestra/backups patch
 - vhd-lib minor
+- xo-vmdk-to-vhd patch
 - xo-server patch
 - xo-server-auth-github patch
 - xo-server-auth-google patch

packages/xo-vmdk-to-vhd/src/ova-read.js

@@ -131,12 +131,24 @@ const allocationUnitsToFactor = unit => {
   return intValue != null ? Math.pow(2, intValue[1]) : MEMORY_UNIT_TO_FACTOR[unit.charAt(0).toLowerCase()]
 }
 
-const filterDisks = disks => {
+const cleanDisks = disks => {
+  const usedPositions = new Set()
+  let nextPosition = Object.keys(disks).length
   for (const diskId in disks) {
-    if (disks[diskId].position == null) {
+    let position = disks[diskId].position
+    if (position == null) {
       // TODO: Log error in U.I.
       console.error(`No position specified for '${diskId}'.`)
       delete disks[diskId]
+    } else {
+      if (usedPositions.has(position)) {
+        console.warn(
+          `There is at least two disks with position ${position}, we're changing the second one to ${nextPosition}`
+        )
+        disks[diskId].position = position = nextPosition
+        nextPosition++
+      }
+      usedPositions.add(position)
     }
   }
 }
@@ -202,7 +214,7 @@ export async function parseOVF(fileFragment, stringDeserializer) {
         forEach(ensureArray(hardware.EthernetPortItem), handleItem)
         // Remove disks which not have a position.
         // (i.e. no info in hardware.Item section.)
-        filterDisks(data.disks)
+        cleanDisks(data.disks)
         resolve(data)
       }
     )