fix(web): reject non-finite JSON numbers instead of raising

POST /api/v3/config/dim-schedule with {"dim_brightness": Infinity} answered
500. So did /api/v3/errors/clear with max_age_hours, and /api/v3/config/main
with multiplexing or row_address_type.

json.loads accepts Infinity/-Infinity/NaN by default -- they are not valid
JSON, but Python's parser emits them -- and Flask's get_json passes them
straight through. int(float('inf')) raises OverflowError, which is neither
ValueError nor TypeError, so validation blocks that carefully caught those let
it past and Flask turned it into a 500.

The status code was not the real damage. dim-schedule answered with
CONFIG_SAVE_FAILED and suggested "Check file permissions on config directory"
and "Check available disk space" for what was an invalid number. Every one of
these sites already had a correct 400 response written; they just never
reached it.

NaN already returned 400, because int(nan) raises ValueError. That is why this
only ever showed up for the infinities, and why it survived: the obvious test
case passes.

OverflowError is now caught alongside ValueError/TypeError at the 27 sites in
this file whose try block performs a numeric coercion. An AST sweep confirms
no int()/float() of request-derived data is left outside a block that catches
it.

Verified end to end through Flask's test client rather than by reasoning about
the parser: all four routes returned 500 before and 400 after.

Tests: five Infinity cases (which fail against the previous except tuples),
two NaN cases pinned so narrowing the tuple cannot quietly break them, and a
check that ordinary input is not rejected by the widened guard.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01STMbQE4YctTacQXfbYqKuW
This commit is contained in:
ChuckBuilds
2026-08-22 16:09:45 -04:00
co-authored by Claude Opus 5
parent 6b74506695
commit 0ca702bebf
2 changed files with 100 additions and 27 deletions
+73
View File
@@ -0,0 +1,73 @@
"""Non-finite JSON numbers must be rejected, not raise.
json.loads accepts Infinity/-Infinity/NaN by default (they are not valid JSON,
but Python's parser emits them) and Flask's get_json passes them straight
through. int(float('inf')) raises OverflowError, which is neither ValueError
nor TypeError -- so validation blocks that carefully caught those let it
through and Flask turned it into a 500.
The damage was not the status code. /config/dim-schedule answered with
CONFIG_SAVE_FAILED and suggested "Check file permissions on config directory"
and "Check available disk space" for what was actually an invalid number.
NaN already returned 400 (int(nan) raises ValueError), which is why this only
showed up for the infinities.
"""
import sys
from pathlib import Path
import pytest
sys.path.insert(0, str(Path(__file__).parent.parent))
from test._api_v3_test_helpers import api_v3_client, api_v3_module # noqa: F401,E402
#: (route, body) pairs that returned 500 before OverflowError was caught.
NON_FINITE_CASES = [
('/api/v3/config/dim-schedule', '{"dim_brightness": Infinity}'),
('/api/v3/config/dim-schedule', '{"dim_brightness": -Infinity}'),
('/api/v3/errors/clear', '{"max_age_hours": Infinity}'),
('/api/v3/config/main', '{"multiplexing": Infinity}'),
('/api/v3/config/main', '{"row_address_type": Infinity}'),
]
@pytest.mark.parametrize("route,body", NON_FINITE_CASES)
def test_infinity_is_a_client_error_not_a_server_error(api_v3_client, route, body):
response = api_v3_client.post(route, data=body, content_type='application/json')
assert response.status_code != 500, (
f"{route} with {body} raised instead of validating"
)
assert 400 <= response.status_code < 500, (
f"{route} answered {response.status_code}; expected a 4xx"
)
@pytest.mark.parametrize("route,body", [
('/api/v3/config/dim-schedule', '{"dim_brightness": NaN}'),
('/api/v3/errors/clear', '{"max_age_hours": NaN}'),
])
def test_nan_is_also_a_client_error(api_v3_client, route, body):
"""int(nan) raises ValueError so this path already worked -- pinned so a
refactor that narrows the except tuple cannot quietly break it."""
response = api_v3_client.post(route, data=body, content_type='application/json')
assert 400 <= response.status_code < 500
def test_a_valid_number_is_not_rejected_by_the_guard(api_v3_client):
"""The widened except must not start swallowing ordinary input.
Asserting on 2xx is not possible here: every manager is a MagicMock, so
the save path fails downstream whatever is posted. What this can show is
that a valid number gets past *validation* -- it is not answered with a
400, and nothing in the response mentions the coercion failing.
"""
response = api_v3_client.post(
'/api/v3/config/dim-schedule',
data='{"dim_brightness": 30}',
content_type='application/json',
)
assert response.status_code != 400, "a valid brightness was rejected"
assert b'must be an integer' not in response.get_data()
assert b'OverflowError' not in response.get_data()
+27 -27
View File
@@ -597,7 +597,7 @@ def save_dim_schedule_config():
dim_brightness = 30 dim_brightness = 30
else: else:
dim_brightness = int(dim_brightness_raw) dim_brightness = int(dim_brightness_raw)
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
return error_response( return error_response(
ErrorCode.VALIDATION_ERROR, ErrorCode.VALIDATION_ERROR,
"dim_brightness must be an integer between 0 and 100", "dim_brightness must be an integer between 0 and 100",
@@ -797,7 +797,7 @@ def save_main_config():
}), 400 }), 400
try: try:
target_fps = int(raw_target_fps) target_fps = int(raw_target_fps)
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
return jsonify({ return jsonify({
'status': 'error', 'status': 'error',
'message': "Invalid value for target_fps: must be an integer" 'message': "Invalid value for target_fps: must be an integer"
@@ -867,7 +867,7 @@ def save_main_config():
mux_val = int(data['multiplexing']) mux_val = int(data['multiplexing'])
if mux_val < 0 or mux_val > 22: if mux_val < 0 or mux_val > 22:
return jsonify({'status': 'error', 'message': f"Invalid multiplexing value '{data['multiplexing']}'. Must be an integer from 0 to 22."}), 400 return jsonify({'status': 'error', 'message': f"Invalid multiplexing value '{data['multiplexing']}'. Must be an integer from 0 to 22."}), 400
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
return jsonify({'status': 'error', 'message': f"Invalid multiplexing value '{data['multiplexing']}'. Must be an integer from 0 to 22."}), 400 return jsonify({'status': 'error', 'message': f"Invalid multiplexing value '{data['multiplexing']}'. Must be an integer from 0 to 22."}), 400
# Validate pixel_mapper_config (free-form mapper string, e.g. "U-mapper;Rotate:90") # Validate pixel_mapper_config (free-form mapper string, e.g. "U-mapper;Rotate:90")
@@ -885,7 +885,7 @@ def save_main_config():
rat_val = int(data['row_address_type']) rat_val = int(data['row_address_type'])
if rat_val < 0 or rat_val > 4: if rat_val < 0 or rat_val > 4:
return jsonify({'status': 'error', 'message': f"Invalid row_address_type '{data['row_address_type']}'. Must be an integer from 0 to 4."}), 400 return jsonify({'status': 'error', 'message': f"Invalid row_address_type '{data['row_address_type']}'. Must be an integer from 0 to 4."}), 400
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
return jsonify({'status': 'error', 'message': f"Invalid row_address_type '{data['row_address_type']}'. Must be an integer from 0 to 4."}), 400 return jsonify({'status': 'error', 'message': f"Invalid row_address_type '{data['row_address_type']}'. Must be an integer from 0 to 4."}), 400
# Handle hardware settings # Handle hardware settings
@@ -910,7 +910,7 @@ def save_main_config():
if rp1_val not in (0, 1): if rp1_val not in (0, 1):
return jsonify({'status': 'error', 'message': "rp1_rio must be 0 (PIO) or 1 (RIO)"}), 400 return jsonify({'status': 'error', 'message': "rp1_rio must be 0 (PIO) or 1 (RIO)"}), 400
current_config['display']['runtime']['rp1_rio'] = rp1_val current_config['display']['runtime']['rp1_rio'] = rp1_val
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
return jsonify({'status': 'error', 'message': "rp1_rio must be 0 or 1"}), 400 return jsonify({'status': 'error', 'message': "rp1_rio must be 0 or 1"}), 400
# Handle checkboxes - coerce to bool to ensure proper JSON types # Handle checkboxes - coerce to bool to ensure proper JSON types
@@ -963,7 +963,7 @@ def save_main_config():
copies = None copies = None
try: try:
copies = int(data['double_sided_copies']) copies = int(data['double_sided_copies'])
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
if enabled: if enabled:
return jsonify({'status': 'error', 'message': "Double-sided copies must be an integer"}), 400 return jsonify({'status': 'error', 'message': "Double-sided copies must be an integer"}), 400
if copies is not None and not (2 <= copies <= 8): if copies is not None and not (2 <= copies <= 8):
@@ -1036,7 +1036,7 @@ def save_main_config():
if data.get('vegas_extend_threshold_screens') not in ('', None): if data.get('vegas_extend_threshold_screens') not in ('', None):
try: try:
screens = float(data['vegas_extend_threshold_screens']) screens = float(data['vegas_extend_threshold_screens'])
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
return jsonify({ return jsonify({
'status': 'error', 'status': 'error',
'message': "Invalid value for vegas_extend_threshold_screens: " 'message': "Invalid value for vegas_extend_threshold_screens: "
@@ -1053,7 +1053,7 @@ def save_main_config():
if data.get('vegas_max_plugin_width_ratio') not in ('', None): if data.get('vegas_max_plugin_width_ratio') not in ('', None):
try: try:
ratio = float(data['vegas_max_plugin_width_ratio']) ratio = float(data['vegas_max_plugin_width_ratio'])
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
return jsonify({ return jsonify({
'status': 'error', 'status': 'error',
'message': "Invalid value for vegas_max_plugin_width_ratio: " 'message': "Invalid value for vegas_max_plugin_width_ratio: "
@@ -1101,7 +1101,7 @@ def save_main_config():
continue continue
try: try:
int_value = int(raw_value) int_value = int(raw_value)
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
return jsonify({ return jsonify({
'status': 'error', 'status': 'error',
'message': f"Invalid value for {field_name}: must be an integer" 'message': f"Invalid value for {field_name}: must be an integer"
@@ -1153,7 +1153,7 @@ def save_main_config():
if not (1024 <= port_val <= 65535): if not (1024 <= port_val <= 65535):
return jsonify({'status': 'error', 'message': "sync_port must be between 1024 and 65535"}), 400 return jsonify({'status': 'error', 'message': "sync_port must be between 1024 and 65535"}), 400
current_config['sync']['port'] = port_val current_config['sync']['port'] = port_val
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
return jsonify({'status': 'error', 'message': "sync_port must be an integer"}), 400 return jsonify({'status': 'error', 'message': "sync_port must be an integer"}), 400
if "sync_follower_position" in data: if "sync_follower_position" in data:
@@ -1197,7 +1197,7 @@ def save_main_config():
raw_value = data.pop(field) raw_value = data.pop(field)
try: try:
int_value = int(raw_value) int_value = int(raw_value)
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
return jsonify({'status': 'error', return jsonify({'status': 'error',
'message': f"Invalid duration for {field}: must be an integer"}), 400 'message': f"Invalid duration for {field}: must be an integer"}), 400
current_config['display']['display_durations'][field] = int_value current_config['display']['display_durations'][field] = int_value
@@ -1220,7 +1220,7 @@ def save_main_config():
continue continue
try: try:
int_value = int(raw_value) int_value = int(raw_value)
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
return jsonify({'status': 'error', return jsonify({'status': 'error',
'message': f"Invalid duration for mode '{mode_key}': must be an integer"}), 400 'message': f"Invalid duration for mode '{mode_key}': must be an integer"}), 400
current_config['display']['display_durations'][mode_key] = int_value current_config['display']['display_durations'][mode_key] = int_value
@@ -5118,7 +5118,7 @@ def save_plugin_config():
converted_array.append(int(v)) converted_array.append(int(v))
else: else:
converted_array.append(float(v)) converted_array.append(float(v))
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
converted_array.append(v) converted_array.append(v)
else: else:
converted_array.append(v) converted_array.append(v)
@@ -5143,7 +5143,7 @@ def save_plugin_config():
converted_array.append(int(v)) converted_array.append(int(v))
else: else:
converted_array.append(float(v)) converted_array.append(float(v))
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
converted_array.append(v) converted_array.append(v)
else: else:
converted_array.append(v) converted_array.append(v)
@@ -5180,7 +5180,7 @@ def save_plugin_config():
converted_array.append(int(v)) converted_array.append(int(v))
else: else:
converted_array.append(float(v)) converted_array.append(float(v))
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
converted_array.append(v) converted_array.append(v)
else: else:
converted_array.append(v) converted_array.append(v)
@@ -5204,7 +5204,7 @@ def save_plugin_config():
converted_array.append(int(v)) converted_array.append(int(v))
else: else:
converted_array.append(float(v)) converted_array.append(float(v))
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
converted_array.append(v) converted_array.append(v)
else: else:
converted_array.append(v) converted_array.append(v)
@@ -5371,7 +5371,7 @@ def save_plugin_config():
if isinstance(v, str): if isinstance(v, str):
try: try:
converted.append(int(v) if item_type == 'integer' else float(v)) converted.append(int(v) if item_type == 'integer' else float(v))
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
converted.append(v) converted.append(v)
else: else:
converted.append(v) converted.append(v)
@@ -5496,7 +5496,7 @@ def save_plugin_config():
try: try:
normalized[key] = int(value_stripped) normalized[key] = int(value_stripped)
continue continue
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
pass pass
elif isinstance(value, (int, float)): elif isinstance(value, (int, float)):
normalized[key] = int(value) normalized[key] = int(value)
@@ -5514,7 +5514,7 @@ def save_plugin_config():
try: try:
normalized[key] = float(value_stripped) normalized[key] = float(value_stripped)
continue continue
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
pass pass
elif isinstance(value, (int, float)): elif isinstance(value, (int, float)):
normalized[key] = float(value) normalized[key] = float(value)
@@ -5569,7 +5569,7 @@ def save_plugin_config():
try: try:
normalized_array.append(int(v)) normalized_array.append(int(v))
continue continue
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
pass pass
elif isinstance(v, (int, float)): elif isinstance(v, (int, float)):
normalized_array.append(int(v)) normalized_array.append(int(v))
@@ -5579,7 +5579,7 @@ def save_plugin_config():
try: try:
normalized_array.append(float(v)) normalized_array.append(float(v))
continue continue
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
pass pass
elif isinstance(v, (int, float)): elif isinstance(v, (int, float)):
normalized_array.append(float(v)) normalized_array.append(float(v))
@@ -5595,7 +5595,7 @@ def save_plugin_config():
if isinstance(v, str): if isinstance(v, str):
try: try:
normalized_array.append(int(v)) normalized_array.append(int(v))
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
normalized_array.append(v) normalized_array.append(v)
elif isinstance(v, (int, float)): elif isinstance(v, (int, float)):
normalized_array.append(int(v)) normalized_array.append(int(v))
@@ -5609,7 +5609,7 @@ def save_plugin_config():
if isinstance(v, str): if isinstance(v, str):
try: try:
normalized_array.append(float(v)) normalized_array.append(float(v))
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
normalized_array.append(v) normalized_array.append(v)
else: else:
normalized_array.append(v) normalized_array.append(v)
@@ -5632,7 +5632,7 @@ def save_plugin_config():
if isinstance(value, str): if isinstance(value, str):
try: try:
normalized[key] = int(value) normalized[key] = int(value)
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
normalized[key] = value normalized[key] = value
else: else:
normalized[key] = value normalized[key] = value
@@ -5641,7 +5641,7 @@ def save_plugin_config():
if isinstance(value, str): if isinstance(value, str):
try: try:
normalized[key] = float(value) normalized[key] = float(value)
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
normalized[key] = value normalized[key] = value
else: else:
normalized[key] = value normalized[key] = value
@@ -6779,7 +6779,7 @@ def get_font_preview() -> tuple[Response, int] | Response:
# Safe integer parsing for size # Safe integer parsing for size
try: try:
size = int(request.args.get('size', 12)) size = int(request.args.get('size', 12))
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
return jsonify({'status': 'error', 'message': 'Invalid font size'}), 400 return jsonify({'status': 'error', 'message': 'Invalid font size'}), 400
if not font_filename: if not font_filename:
@@ -8360,7 +8360,7 @@ def clear_old_errors():
context={'provided_value': raw_max_age}, context={'provided_value': raw_max_age},
status_code=400 status_code=400
) )
except (ValueError, TypeError): except (ValueError, TypeError, OverflowError):
return error_response( return error_response(
error_code=ErrorCode.INVALID_INPUT, error_code=ErrorCode.INVALID_INPUT,
message="max_age_hours must be a valid integer", message="max_age_hours must be a valid integer",