test: verify IPC error handling for invalid coinbase
What the developer wrote
Authored by Enoch Azariah
test: verify IPC error handling for invalid coinbase
Add a test case to interface_ipc_mining.py to verify that the IPC
server correctly handles and reports serialization errors rather than
crashing the node.
This covers the scenario where submitSolution is called with data
that cannot be deserialized, as discussed in #33341
Also introduces the assert_capnp_failed helper in ipc_util.py to
cleanly handle macOS-specific Cap'n Proto exception strings, and
refactors an existing block weight test to use it.
What changed, and why it matters
This commit only adds a new automated test and a small test helper. It checks that the Bitcoin Core IPC mining server returns a clean error when given invalid data, instead of crashing. There is no change to production code, so it does not introduce or fix a live security vulnerability by itself.
No immediate action required; this is a regression test. If the underlying issue (#33341) has not already been fixed in production code, ensure the node-side IPC deserialization path is hardened separately.
Security signals we found
Test-only change verifying error handling for malformed IPC input
References prior discussion (#33341) about IPC server behavior on invalid coinbase data
No production code patch present in the diff
Evidence from the diff
The diff is test-only: it adds assert_capnp_failed to test_framework/ipc_util.py and uses it in interface_ipc_mining.py to verify that submitSolution with an empty/deserialization-failing payload raises a Cap’n Proto KjException with type FAILED and a SpanReader::read(): end of data: message. An existing block-weight assertion is refactored to use the same helper. No node-side source code is modified.
Changed components
test/functional/interface_ipc_mining.pytest/functional/test_framework/ipc_util.pyInspect captured patch +24 / −10
diff --git a/test/functional/interface_ipc_mining.py b/test/functional/interface_ipc_mining.py
index 6f2237a8..0c3b9cf8 100755
--- a/test/functional/interface_ipc_mining.py
+++ b/test/functional/interface_ipc_mining.py
@@ -7,7 +7,6 @@ import asyncio
import time
from contextlib import AsyncExitStack
from io import BytesIO
-import platform
from test_framework.blocktools import NULL_OUTPOINT
from test_framework.messages import (
MAX_BLOCK_WEIGHT,
@@ -42,6 +41,7 @@ from test_framework.ipc_util import (
mining_wait_next_template,
wait_and_do,
make_mining_ctx,
+ assert_capnp_failed
)
# Test may be skipped and not have capnp installed
@@ -325,15 +325,7 @@ class IPCMiningTest(BitcoinTestFramework):
await mining.createNewBlock(ctx, opts)
raise AssertionError("createNewBlock unexpectedly succeeded")
except capnp.lib.capnp.KjException as e:
- if e.description == "remote exception: unknown non-KJ exception of type: kj::Exception":
- # macOS + REDUCE_EXPORTS bug: Cap'n Proto fails to recognize
- # its own exception type and returns a generic error instead.
- # https://github.com/bitcoin/bitcoin/pull/34422#discussion_r2863852691
- # Assert this only occurs on Darwin until fixed.
- assert_equal(platform.system(), "Darwin")
- else:
- assert_equal(e.description, "remote exception: std::exception: block_reserved_weight (0) must be at least 2000 weight units")
- assert_equal(e.type, "FAILED")
+ assert_capnp_failed(e, "remote exception: std::exception: block_reserved_weight (0) must be at least 2000 weight units")
asyncio.run(capnp.run(async_routine()))
@@ -357,6 +349,13 @@ class IPCMiningTest(BitcoinTestFramework):
block.hashMerkleRoot = block.calc_merkle_root()
original_version = block.nVersion
+ self.log.debug("Submit solution that can't be deserialized")
+ try:
+ await template.submitSolution(ctx, 0, 0, 0, b"")
+ raise AssertionError("submitSolution unexpectedly succeeded")
+ except capnp.lib.capnp.KjException as e:
+ assert_capnp_failed(e, "remote exception: std::exception: SpanReader::read(): end of data:")
+
self.log.debug("Submit a block with a bad version")
block.nVersion = 0
block.solve()
diff --git a/test/functional/test_framework/ipc_util.py b/test/functional/test_framework/ipc_util.py
index c80f78f7..03e3b5d5 100644
--- a/test/functional/test_framework/ipc_util.py
+++ b/test/functional/test_framework/ipc_util.py
@@ -10,9 +10,13 @@ from dataclasses import dataclass
from io import BytesIO
from pathlib import Path
import shutil
+import platform
from typing import Optional
from test_framework.messages import CBlock
+from test_framework.util import (
+ assert_equal
+)
# Test may be skipped and not have capnp installed
try:
@@ -155,3 +159,14 @@ async def make_mining_ctx(self):
self.log.debug("Create Mining proxy object")
mining = init.makeMining(ctx).result
return ctx, mining
+
+def assert_capnp_failed(e, description_prefix):
+ if e.description == "remote exception: unknown non-KJ exception of type: kj::Exception":
+ # macOS + REDUCE_EXPORTS bug: Cap'n Proto fails to recognize
+ # its own exception type and returns a generic error instead.
+ # https://github.com/bitcoin/bitcoin/pull/34422#discussion_r2863852691
+ # Assert this only occurs on Darwin until fixed.
+ assert_equal(platform.system(), "Darwin")
+ else:
+ assert e.description.startswith(description_prefix), f"Expected description starting with '{description_prefix}', got '{e.description}'"
+ assert_equal(e.type, "FAILED")
Why this scored 12/100
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