{"abstract":"The lease release operation is admitted even though a release applies to a different leased resource.","category":"Concurrency","checks":9,"contract":"Return a Boolean admission decision for release a coordination lease. The record r must satisfy all of: r['owner_match'][0] == r['owner_match'][1]; r['acquisition_match'][0] == r['acquisition_match'][1]; r['resource_match'][0] == r['resource_match'][1]; r['release_not_seen'] is False; r['successor_protected'][0] <= r['successor_protected'][1]. Extra tracing fields are ignored; validation does not mutate the record.","evaluation_group":"xd-lease-release","failed_approach":"Adding the resource match check repairs the reported defect, but replacing the adjacent release not seen check loses that independent invariant.","family":"xd-lease-release-resource_match","id":"FA-1511","implementations":{"attempt":{"sha256":"6a7f40af8707226121fa65516fff7faa762a076393cc77076577d6f6990db5b0","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(r):\n    return (r['owner_match'][0] == r['owner_match'][1]) and (r['acquisition_match'][0] == r['acquisition_match'][1]) and (r['resource_match'][0] == r['resource_match'][1]) and (r['successor_protected'][0] <= r['successor_protected'][1])\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nr = {'owner_match': ['a', 'a'], 'acquisition_match': [4, 4], 'resource_match': ['r1', 'r1'], 'release_not_seen': False, 'successor_protected': [4, 4]}\ncheck('valid operation', solve(r), True)\ncheck('One owner releases another owner lease', solve(dict(r, **{'owner_match': ['b', 'a']})), False)\ncheck('A delayed release deletes a later acquisition by the same owner', solve(dict(r, **{'acquisition_match': [3, 4]})), False)\ncheck('A release applies to a different leased resource', solve(dict(r, **{'resource_match': ['r2', 'r1']})), False)\ncheck('Retried release decrements live-lease accounting twice', solve(dict(r, **{'release_not_seen': True})), False)\ncheck('Release removes successor state after ownership transfer', solve(dict(r, **{'successor_protected': [5, 4]})), False)\ncheck('unrelated tracing metadata', solve(dict(r, trace='run-'+str(N))), True)\ncheck('repeat validation is pure', solve(r), True)\ninvalid = {'owner_match': ['b', 'a'], 'acquisition_match': [3, 4], 'resource_match': ['r2', 'r1'], 'release_not_seen': True, 'successor_protected': [5, 4]}\nkeys = list(invalid)\npair = {keys[N % len(keys)]: invalid[keys[N % len(keys)]], keys[(N+1) % len(keys)]: invalid[keys[(N+1) % len(keys)]]}\ncheck('two independent violations in variant', solve(dict(r, **pair)), False)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"517d1bcbad101122993fd598aad5231c8b99fd48d0be160926fdc95fcb4e8852","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(r):\n    return (r['owner_match'][0] == r['owner_match'][1]) and (r['acquisition_match'][0] == r['acquisition_match'][1]) and (r['release_not_seen'] is False) and (r['successor_protected'][0] <= r['successor_protected'][1])\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nr = {'owner_match': ['a', 'a'], 'acquisition_match': [4, 4], 'resource_match': ['r1', 'r1'], 'release_not_seen': False, 'successor_protected': [4, 4]}\ncheck('valid operation', solve(r), True)\ncheck('One owner releases another owner lease', solve(dict(r, **{'owner_match': ['b', 'a']})), False)\ncheck('A delayed release deletes a later acquisition by the same owner', solve(dict(r, **{'acquisition_match': [3, 4]})), False)\ncheck('A release applies to a different leased resource', solve(dict(r, **{'resource_match': ['r2', 'r1']})), False)\ncheck('Retried release decrements live-lease accounting twice', solve(dict(r, **{'release_not_seen': True})), False)\ncheck('Release removes successor state after ownership transfer', solve(dict(r, **{'successor_protected': [5, 4]})), False)\ncheck('unrelated tracing metadata', solve(dict(r, trace='run-'+str(N))), True)\ncheck('repeat validation is pure', solve(r), True)\ninvalid = {'owner_match': ['b', 'a'], 'acquisition_match': [3, 4], 'resource_match': ['r2', 'r1'], 'release_not_seen': True, 'successor_protected': [5, 4]}\nkeys = list(invalid)\npair = {keys[N % len(keys)]: invalid[keys[N % len(keys)]], keys[(N+1) % len(keys)]: invalid[keys[(N+1) % len(keys)]]}\ncheck('two independent violations in variant', solve(dict(r, **pair)), False)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"fixed":{"sha256":"80efec07898498973c6efedd2d507e38c96f681f84efc4d1fe9073e4362c5442","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(r):\n    return (r['owner_match'][0] == r['owner_match'][1]) and (r['acquisition_match'][0] == r['acquisition_match'][1]) and (r['resource_match'][0] == r['resource_match'][1]) and (r['release_not_seen'] is False) and (r['successor_protected'][0] <= r['successor_protected'][1])\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nr = {'owner_match': ['a', 'a'], 'acquisition_match': [4, 4], 'resource_match': ['r1', 'r1'], 'release_not_seen': False, 'successor_protected': [4, 4]}\ncheck('valid operation', solve(r), True)\ncheck('One owner releases another owner lease', solve(dict(r, **{'owner_match': ['b', 'a']})), False)\ncheck('A delayed release deletes a later acquisition by the same owner', solve(dict(r, **{'acquisition_match': [3, 4]})), False)\ncheck('A release applies to a different leased resource', solve(dict(r, **{'resource_match': ['r2', 'r1']})), False)\ncheck('Retried release decrements live-lease accounting twice', solve(dict(r, **{'release_not_seen': True})), False)\ncheck('Release removes successor state after ownership transfer', solve(dict(r, **{'successor_protected': [5, 4]})), False)\ncheck('unrelated tracing metadata', solve(dict(r, trace='run-'+str(N))), True)\ncheck('repeat validation is pure', solve(r), True)\ninvalid = {'owner_match': ['b', 'a'], 'acquisition_match': [3, 4], 'resource_match': ['r2', 'r1'], 'release_not_seen': True, 'successor_protected': [5, 4]}\nkeys = list(invalid)\npair = {keys[N % len(keys)]: invalid[keys[N % len(keys)]], keys[(N+1) % len(keys)]: invalid[keys[(N+1) % len(keys)]]}\ncheck('two independent violations in variant', solve(dict(r, **pair)), False)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":" This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"xd-lease-release-resource_match","generated_at":"2026-09-29T14:37:02.974218+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A deterministic local contract for concurrency. Each negative fixture violates exactly one invariant. No transport timing, persistence, cryptographic verification, or full protocol implementation is claimed.","repair":"Require r['resource_match'][0] == r['resource_match'][1] together with every other stated precondition before accepting the operation.","root_cause":"The admission path omits the resource match invariant while validating the other operation preconditions.","sha256":"571446c6b7e0ef69830dc4fe48a6094ebbb3e04e135ca781239dd3e81cf0d75a","title":"Release a coordination lease: A release applies to a different leased resource · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":31.335,"exit_code":1,"observations":[{"actual":true,"check":"valid operation","expected":true,"passed":true},{"actual":false,"check":"One owner releases another owner lease","expected":false,"passed":true},{"actual":false,"check":"A delayed release deletes a later acquisition by the same owner","expected":false,"passed":true},{"actual":false,"check":"A release applies to a different leased resource","expected":false,"passed":true},{"actual":true,"check":"Retried release decrements live-lease accounting twice","expected":false,"passed":false},{"actual":false,"check":"Release removes successor state after ownership transfer","expected":false,"passed":true},{"actual":true,"check":"unrelated tracing metadata","expected":true,"passed":true},{"actual":true,"check":"repeat validation is pure","expected":true,"passed":true},{"actual":false,"check":"two independent violations in variant","expected":false,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"valid operation\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"One owner releases another owner lease\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"A delayed release deletes a later acquisition by the same owner\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"A release applies to a different leased resource\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"Retried release decrements live-lease accounting twice\", \"actual\": true, \"expected\": false, \"passed\": false}, {\"check\": \"Release removes successor state after ownership transfer\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"unrelated tracing metadata\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"repeat validation is pure\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"two independent violations in variant\", \"actual\": false, \"expected\": false, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":32.515,"exit_code":1,"observations":[{"actual":true,"check":"valid operation","expected":true,"passed":true},{"actual":false,"check":"One owner releases another owner lease","expected":false,"passed":true},{"actual":false,"check":"A delayed release deletes a later acquisition by the same owner","expected":false,"passed":true},{"actual":true,"check":"A release applies to a different leased resource","expected":false,"passed":false},{"actual":false,"check":"Retried release decrements live-lease accounting twice","expected":false,"passed":true},{"actual":false,"check":"Release removes successor state after ownership transfer","expected":false,"passed":true},{"actual":true,"check":"unrelated tracing metadata","expected":true,"passed":true},{"actual":true,"check":"repeat validation is pure","expected":true,"passed":true},{"actual":false,"check":"two independent violations in variant","expected":false,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"valid operation\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"One owner releases another owner lease\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"A delayed release deletes a later acquisition by the same owner\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"A release applies to a different leased resource\", \"actual\": true, \"expected\": false, \"passed\": false}, {\"check\": \"Retried release decrements live-lease accounting twice\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"Release removes successor state after ownership transfer\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"unrelated tracing metadata\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"repeat validation is pure\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"two independent violations in variant\", \"actual\": false, \"expected\": false, \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":33.212,"exit_code":0,"observations":[{"actual":true,"check":"valid operation","expected":true,"passed":true},{"actual":false,"check":"One owner releases another owner lease","expected":false,"passed":true},{"actual":false,"check":"A delayed release deletes a later acquisition by the same owner","expected":false,"passed":true},{"actual":false,"check":"A release applies to a different leased resource","expected":false,"passed":true},{"actual":false,"check":"Retried release decrements live-lease accounting twice","expected":false,"passed":true},{"actual":false,"check":"Release removes successor state after ownership transfer","expected":false,"passed":true},{"actual":true,"check":"unrelated tracing metadata","expected":true,"passed":true},{"actual":true,"check":"repeat validation is pure","expected":true,"passed":true},{"actual":false,"check":"two independent violations in variant","expected":false,"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"valid operation\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"One owner releases another owner lease\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"A delayed release deletes a later acquisition by the same owner\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"A release applies to a different leased resource\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"Retried release decrements live-lease accounting twice\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"Release removes successor state after ownership transfer\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"unrelated tracing metadata\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"repeat validation is pure\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"two independent violations in variant\", \"actual\": false, \"expected\": false, \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}