---
id: "bug-1977"
status: "fixed"
status_updated: "2026-10-28"
status_note: ""
component: "controller"
severity: "crash"
timestamp: "2026-10-28T11:56:58Z"
last_seen: "2026-10-28T11:56:58Z"
occurrences: 1
files: ["src/controller/testsuite/test_config_resource_reconcile.c"]
tags: ["testsuite", "asan"]
related: []
fix_commits: ["8c1995c2"]
---

# bug-1977: crr_build_config callers' stack arrays smaller than builder -- ASAN stack overflow

## Description
**Observed:**
```
ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7ffc...
WRITE of size 8 at 0x7ffc... thread T0
    #0 crr_build_config testsuite/test_config_resource_reconcile.c:126   (dists[3] = &d4)
    #1 test_reconcile_resources_registers_and_seeds_shared_pools testsuite/test_config_resource_reconcile.c:161
```
Every test in the file that calls `crr_build_config` crashes the same way;
the full controller suite reports 137/137 FAIL (meson reports each fixture
crash as its own failure).

**Expected:** all four callers pass arrays large enough for the builder's
fixtures; the suite stays green.

**Impact:** the whole controller testsuite was unrunnable under ASAN since the
external-license-resources test fixtures landed (commit 2fcacac2) -- any
regression in the suite was invisible behind the deterministic crash.

**Found by:** ASAN -- full regression build for the license-resource feature
(`src/tools/xce-build.sh controller`, profile=asan).

## Environment
- OS: Ubuntu 24.04.2 LTS; kernel Linux 6.8.0-147-generic x86_64
- libc: host ldd reports glibc 2.39
- Toolchain: gcc (GCC) 15.2.0, meson 1.9.1
- Build: asan (xce.build)
- Code: feature/license-resources @ 30c51ea1-dirty (introduced by 2fcacac2)
- Deployment: n/a (unit testsuite only)

## Reproduction
1. `src/tools/xce-build.sh controller` (asan profile) -- meson test crashes:
   `controller - xce:controller test` FAIL with the stack-buffer-overflow above.
- Frequency: deterministic
- Evidence: src/testlogs.archive/xce.build/this-20261028-114408-rc1/meson-logs/testlog.txt (bug-1971 failure-preservation mechanism)

## Root cause
`crr_build_config` (test_config_resource_reconcile.c:70) registers FIVE
resources (lic1/hostres/dyn1/extlic/slots -> writes `resources[4]`) and FOUR
distributions (writes `dists[3]`) and FIVE vals (writes `vals[4]`). The four
caller test functions declared only
`resources[4] / dists[3] / vals[4]`, so the builder's writes to index 4 / 3 /
4 overflowed the callers' stack arrays. When the extlic E2 tests were added to
the builder's fixture set (2fcacac2), none of the caller declarations were
resized. (Earlier builds of this branch compiled only a worker-focused subset
-- `test_config_resource_reconcile` was not linked -- so the overflow went
unnoticed until the full controller suite was built.)

## Fix
Resize all four caller arrays to match the builder: `resources[5]`,
`dists[4]`, `vals[5]`, each with a bug-1977 comment pointing at the sizing
contract. Files: src/controller/testsuite/test_config_resource_reconcile.c
(test_reconcile_resources_registers_and_seeds_shared_pools,
test_reconcile_resources_registers_new_defs_past_eexist,
test_reconcile_resources_hot_applies_changed_definition,
test_reconcile_resources_is_idempotent_and_hot_applies).

## Verification
- Test: whole-file suite `controller - xce:controller test` (meson): RED
  137/137 before the fix, GREEN after.
- Suites: `src/tools/xce-build.sh controller` profile=asan: 6/6 OK
  (sched push, sched worker change, apiserver push, host runusage, no-fork
  rule, controller 91s).
- Live: n/a (testsuite-only defect; no production code touched).

## References
- Related: none