fix(caldav): include owner in calendar ID hash to prevent PK collision (#2765)

_stable_cal_id hashed only the remote URL, producing the same calendar
ID for all users syncing the same CalDAV endpoint. The second user would
get an IntegrityError on the primary key. Now includes owner in the
hash so each user gets a distinct calendar row.

routes/document_routes.py

@@ -663,8 +663,9 @@ def setup_document_routes(session_manager, upload_handler=None) -> APIRouter:
         try:
             # Verify ownership before listing versions
             doc = db.query(Document).filter(Document.id == doc_id).first()
-            if doc:
-                _verify_doc_owner(db, doc, user)
+            if not doc:
+                raise HTTPException(404, "Document not found")
+            _verify_doc_owner(db, doc, user)
             versions = db.query(DocumentVersion).filter(
                 DocumentVersion.document_id == doc_id
             ).order_by(DocumentVersion.version_number.desc()).all()
@@ -687,8 +688,9 @@ def setup_document_routes(session_manager, upload_handler=None) -> APIRouter:
         try:
             # Verify ownership
             doc = db.query(Document).filter(Document.id == doc_id).first()
-            if doc:
-                _verify_doc_owner(db, doc, user)
+            if not doc:
+                raise HTTPException(404, "Document not found")
+            _verify_doc_owner(db, doc, user)
             ver = db.query(DocumentVersion).filter(
                 DocumentVersion.document_id == doc_id,
                 DocumentVersion.version_number == num,

routes/gallery_routes.py

@@ -1316,6 +1316,7 @@ def setup_gallery_routes() -> APIRouter:
     @router.post("/api/image/sharpen")
     async def sharpen_image(request: Request):
         """Apply unsharp-mask sharpening to an image."""
+        require_privilege(request, "can_generate_images")
         body = await request.json()
         image_b64 = body.get("image")
         amount = body.get("amount", 50) / 100.0

routes/task_routes.py

@@ -497,6 +497,15 @@ def setup_task_routes(task_scheduler) -> APIRouter:
                 else bool(req.notifications_enabled) if req.notifications_enabled is not None
                 else True
             )
+            # Validate chained task belongs to same owner
+            if req.then_task_id:
+                chain_target = db.query(ScheduledTask).filter(
+                    ScheduledTask.id == req.then_task_id
+                ).first()
+                if not chain_target:
+                    raise HTTPException(400, "Chained task not found")
+                if chain_target.owner != user:
+                    raise HTTPException(403, "Cannot chain to another user's task")
             task = ScheduledTask(
                 id=task_id,
                 owner=user,
@@ -671,6 +680,14 @@ def setup_task_routes(task_scheduler) -> APIRouter:
             if req.trigger_count is not None:
                 task.trigger_count = req.trigger_count
             if req.then_task_id is not None:
+                if req.then_task_id:
+                    chain_target = db.query(ScheduledTask).filter(
+                        ScheduledTask.id == req.then_task_id
+                    ).first()
+                    if not chain_target:
+                        raise HTTPException(400, "Chained task not found")
+                    if chain_target.owner != user:
+                        raise HTTPException(403, "Cannot chain to another user's task")
                 task.then_task_id = req.then_task_id or None
             if req.notifications_enabled is not None:
                 task.notifications_enabled = bool(req.notifications_enabled)

src/caldav_sync.py

@@ -86,10 +86,12 @@ def validate_caldav_url(raw_url: str) -> str:
     return urlunparse(parsed._replace(fragment="")).rstrip("/")
 
 
-def _stable_cal_id(remote_url: str) -> str:
+def _stable_cal_id(remote_url: str, owner: str = "") -> str:
     """Deterministic local id for a remote CalDAV calendar — same URL
-    always maps to the same local row across restarts and re-syncs."""
-    h = hashlib.sha256(remote_url.encode("utf-8")).hexdigest()[:24]
+    always maps to the same local row across restarts and re-syncs.
+    Owner is included in the hash to prevent PK collisions when multiple
+    users sync the same CalDAV endpoint."""
+    h = hashlib.sha256(f"{owner}:{remote_url}".encode("utf-8")).hexdigest()[:24]
     return f"caldav-{h}"
 
 
@@ -170,7 +172,7 @@ def _sync_blocking(owner: str, url: str, username: str, password: str) -> dict:
         for remote_cal in calendars:
             try:
                 remote_url = str(remote_cal.url)
-                cal_id = _stable_cal_id(remote_url)
+                cal_id = _stable_cal_id(remote_url, owner)
                 display_name = (remote_cal.name or "").strip() or "CalDAV"
 
                 local_cal = db.query(CalendarCal).filter(