---
id: "bug-1401"
status: "fixed"
status_updated: "2026-09-24"
status_note: ""
component: "lib"
severity: "leak"
timestamp: "2026-07-02T14:25:00.000Z"
last_seen: "2026-09-19T09:00:00Z"
occurrences: 1
files: ["src/lib/controller.capnp.c (decode_CtrlStatus_ptr", "generated codec) or its caller in request.c/xcecli"]
tags: ["asan", "low-priority", "controller-status", "ctrlstatus", "memory-leak"]
related: []
legacy: true
---

# bug-1401: ASAN LeakSanitizer: every ctrlstatus reply leaks memory in decode_CtrlStatus_ptr…

## Description
ASAN LeakSanitizer: every ctrlstatus reply leaks memory in decode_CtrlStatus_ptr (lib/controller.capnp.c:11873) — observed during ha-heartbeat-committed-propagation task 4.1 live validation: 120 bytes/1 alloc after a single ctrlstatus call, 12360 bytes/103 allocs after ~a dozen calls (roughly proportional to call count).

## Environment
_Not recorded (migrated from buglog.json)._

## Reproduction
_Not recorded (migrated from buglog.json)._

## Root cause
CONFIRMED via codegraph + generated codec trace: src/include/client.h:119 defined `xce_free_ctrlstatus(s)` as `free_CtrlStatus(s)` — the generated free_CtrlStatus() only frees the FIELDS INSIDE the xce_ctrlstatus_t (clusterName/primaryName/responderName/configChecksum/peers list), matching decode_CtrlStatus(). But the real client reply path (xce_handle_reply -> MOVE_PTR from the decoded RequestReply -> xce_ctrlstatus) populates the struct via decode_CtrlStatus_PTR(), which calloc's the xce_ctrlstatus_t itself (controller.capnp.c:11873) before calling decode_CtrlStatus() to fill it. Only free_CtrlStatus_ptr() (which calls free_CtrlStatus() THEN free()s the struct and nulls the caller's pointer) matches that allocation. free_RequestReply/free_Request/MOVE_PTR were all confirmed symmetric and correct — the bug was isolated to this one macro definition. Existing unit tests never caught it because they call free_CtrlStatus(&out) directly on a stack struct, never exercising the xce_free_ctrlstatus() macro used by real client code.

## Fix
src/include/client.h:119 changed to `#define xce_free_ctrlstatus(s) free_CtrlStatus_ptr(&(s))`. Added regression test test_xce_free_ctrlstatus_frees_the_struct_itself (src/lib/testsuite/test_ctrlstatus.c), which decodes via decode_CtrlStatus_ptr (the real allocation path, not the stack-struct helper the other roundtrip tests use) and frees via the xce_free_ctrlstatus macro. RED confirmed: reverting the fix reproduces the exact reported leak signature (LeakSanitizer: 120 bytes in 1 object, decode_CtrlStatus_ptr calloc). GREEN after fix: 285 lib tests / 0 failures / 0 leaks. Controller ASAN build + controller_unit_test also green post-fix (client.h is shared).

## Verification
_Not recorded (migrated from buglog.json)._

## References
_Not recorded (migrated from buglog.json)._