Do not attempt to read from read buffer if client disconnects during fuzzing#100732
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antaljanosbenjamin wants to merge 2 commits intomasterfrom
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Do not attempt to read from read buffer if client disconnects during fuzzing#100732antaljanosbenjamin wants to merge 2 commits intomasterfrom
antaljanosbenjamin wants to merge 2 commits intomasterfrom
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…fuzzing Some info about what went wrong: Root cause: The AST fuzzer (executeASTFuzzerQueries) runs fuzzed internal queries after the original query completes (via onFinish() callback). These internal queries inherit the outer query's InteractiveCancelCallback through CurrentThread::tryGetQueryContext(). When JoinOrderOptimizer::checkLimits() invokes this callback, it calls receivePacketsExpectCancel() which reads from the TCP input buffer in. If the client has disconnected, in gets canceled. The fuzzer's catch(...) swallows the exception and continues. When the fuzzer finishes and the TCPHandler loop calls in->eof(), the chassert(!isCanceled()) in ReadBuffer::next() fires.
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Workflow [PR], commit [68d3e4d] Summary: ❌
AI ReviewSummaryThis PR fixes a real cancellation-path issue during AST fuzzing: fuzzed internal queries inherited an interactive cancel callback tied to the client connection, which could cancel the input buffer and later trigger an exception when Missing context
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PR changed lines: PR changed-lines coverage: 100.00% (15/15, 0 noise lines excluded) |
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Some info about what went wrong:
Root cause: The AST fuzzer (
executeASTFuzzerQueries) runs fuzzed internal queries after the original query completes (viaonFinish()callback). These internal queries inherit the outer query'sInteractiveCancelCallbackthroughCurrentThread::tryGetQueryContext(). WhenJoinOrderOptimizer::checkLimits()invokes this callback, it callsreceivePacketsExpectCancel()which reads from the TCP input buffer in. If the client has disconnected, in gets canceled. The fuzzer'scatch(...)swallows the exception and continues. When the fuzzer finishes and theTCPHandlerloop callsin->eof(), thechassert(!isCanceled())inReadBuffer::next()fires.Changelog category (leave one):
Documentation entry for user-facing changes