Enforce HTTP/2 MAX_CONCURRENT_STREAMS with REFUSED_STREAM - #40
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For locally-served chunked requests the only size guard compared
maxDecodedBodyBytes against ChunkedBodyScanner.decodedByteCount(), which counts
only chunk DATA bytes. Chunk-extension (SIZE_EXT), trailer, and unrecognized
size-line bytes are consumed uncounted while every raw byte is still forwarded
to LocalHttpRequestStage's unbounded bodyBuffer, so an endless chunk-extension
("1;AAAA...") or trailer buffers to OutOfMemoryError regardless of the
configured ceiling — one unauthenticated connection crashes the JVM.
Have ChunkedBodyScanner track rawByteCount() (framing + data) alongside
decodedByteCount(), and enforce a total raw-byte ceiling in
HttpServerStage.readBody next to the decoded one: 2x maxDecodedBodyBytes + 8 KiB
(finite, proportional so it does not false-positive on legitimate many-chunk
bodies; off when the policy is unlimited). Per-element caps alone don't suffice
— many tiny data chunks each with a capped extension still aggregate past the
decoded ceiling; a raw bound covers all framing variants. Also give the SIZE
state a terminal else so a non-hex size-line byte errors (400) instead of being
silently consumed.
Tests: ChunkedBodyScannerTest.invalidCharInSizeLine_setsError and
rawByteCount_countsFramingAndData;
ChunkedBodyIntegrationTest.chunkedFramingBytesBoundedBy413 (20 KB extension
under an 8-byte policy -> 413).
Verification (background; SKIP_PRECOMMIT=1, inline coverage exceeds the 2-min
foreground limit):
* bazel test //... 18/18 (--flaky_test_attempts=3)
* coverage-gate 92.43% (7837/8479) >= 90%
* bazel run //:format.check clean
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
We advertise SETTINGS_MAX_CONCURRENT_STREAMS=100 but never enforced it, so a peer that ignores the advertised limit could open unbounded streams and grow the streams map (and, transitively, heldRequests) without limit. Refuse a HEADERS frame that would exceed the limit with RST_STREAM (REFUSED_STREAM, retryable) instead of opening the stream (RFC 9113 §5.1.2). The streams map holds exactly the open/half-closed streams that count toward the limit, and heldRequests entries are a subset of open streams, so both are now bounded. HPACK is decoded first so the connection-global dynamic table stays in sync whether or not the stream is refused. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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We advertise SETTINGS_MAX_CONCURRENT_STREAMS=100 but never enforced it, so
a peer that ignores the advertised limit could open unbounded streams and
grow the streams map (and, transitively, heldRequests) without limit.
Refuse a HEADERS frame that would exceed the limit with RST_STREAM
(REFUSED_STREAM, retryable) instead of opening the stream (RFC 9113 §5.1.2).
The streams map holds exactly the open/half-closed streams that count toward
the limit, and heldRequests entries are a subset of open streams, so both are
now bounded. HPACK is decoded first so the connection-global dynamic table
stays in sync whether or not the stream is refused.
Co-Authored-By: Claude Opus 4.8 noreply@anthropic.com