dedupe duplicate mount points when recreating a container

src/lib/server/mount-dedupe.ts

@@ -1,4 +1,5 @@
 type HostConfigLike = {
+	Tmpfs?: Record<string, string> | null;
 	Binds?: string[] | null;
 	Mounts?: Array<{ Target?: string | null }> | null;
 };
@@ -9,6 +10,41 @@ type InspectMountLike = {
 	Destination?: string | null;
 };
 
+/** Destination path of a bind string ("src:/dst:ro" -> "/dst", "/dst" -> "/dst"). */
+function bindTarget(bind: string): string {
+	const parts = bind.split(':');
+	return parts.length >= 2 ? parts[1] : parts[0];
+}
+
+/**
+ * Drop Config.Volumes entries whose path is already mounted, so recreate never sends a duplicate
+ * mount point (#1088 / #1363). The path can be occupied by Tmpfs, an existing bind, a bind we're
+ * ABOUT to add (getAdditionalVolumeBinds), or a volume that shows up only in inspect.Mounts (the
+ * shape a remote/hawser daemon returns) - the earlier fix checked Tmpfs/Binds only, so a named
+ * volume at an image-VOLUME path (e.g. cups /etc/cups) slipped through and collided with the bind
+ * re-added from inspect.Mounts. Checking all four sources in one place closes that gap.
+ */
+export function dedupeVolumesForRecreate(
+	volumes: Record<string, unknown> | undefined | null,
+	hostConfig: HostConfigLike,
+	mounts: InspectMountLike[],
+	additionalBinds: string[]
+): Record<string, unknown> | undefined {
+	if (!volumes) return undefined;
+	const mounted = new Set<string>();
+	for (const p of Object.keys(hostConfig.Tmpfs || {})) mounted.add(p);
+	for (const b of hostConfig.Binds || []) mounted.add(bindTarget(b));
+	for (const b of additionalBinds) mounted.add(bindTarget(b));
+	for (const m of hostConfig.Mounts || []) { if (m?.Target) mounted.add(m.Target); }
+	for (const m of mounts || []) { if (m.Destination) mounted.add(m.Destination); }
+
+	const kept: Record<string, unknown> = {};
+	for (const [path, val] of Object.entries(volumes)) {
+		if (!mounted.has(path)) kept[path] = val;
+	}
+	return Object.keys(kept).length > 0 ? kept : undefined;
+}
+
 /** Build extra bind strings for volume mounts missing from HostConfig. */
 export function getAdditionalVolumeBinds(
 	hostConfig: HostConfigLike,

src/routes/api/self-update/+server.ts

@@ -1,6 +1,6 @@
 import { json } from '@sveltejs/kit';
 import { authorize } from '$lib/server/authorize';
-import { getAdditionalVolumeBinds } from '$lib/server/mount-dedupe';
+import { getAdditionalVolumeBinds, dedupeVolumesForRecreate } from '$lib/server/mount-dedupe';
 import {
 	getOwnContainerId,
 	getHostDockerSocket,
@@ -169,6 +169,11 @@ function buildCreateConfig(inspectData: any, newImage: string): any {
 	delete createConfig.Hostname;
 
 	const additionalBinds = getAdditionalVolumeBinds(hostConfig, inspectData.Mounts || []);
+	// Drop image-VOLUME entries that collide with a bind/tmpfs/inspect mount, so create never
+	// sends a duplicate mount point (#1088 / #1363).
+	const kept = dedupeVolumesForRecreate(createConfig.Volumes, hostConfig, inspectData.Mounts || [], additionalBinds);
+	if (kept) createConfig.Volumes = kept;
+	else delete createConfig.Volumes;
 	if (additionalBinds.length > 0) {
 		createConfig.HostConfig = {
 			...createConfig.HostConfig,