fix: connection level flow control accounting for empty, non-fin frames#2491
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fix: connection level flow control accounting for empty, non-fin frames#2491gregor-cf wants to merge 1 commit into
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csujedihy
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ghedo
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This fixes a bug in connection level flow control accounting. When an empty STREAM frame without FIN is received, we calcuate the difference between the highest previously received offset and the frame's max_off and add that to connection level flow control. However, in `RecvBuf::write()` we return early and we do not update the highest received offset. On subsequent frames, we count the same bytes against conn level flow control again. To fix this, we update the highest receive offset in RecvBuf::write(). The alternative would be to ignore such frames, but I think updating the high water mark is the right choice: It mimmicks what we do for empty FIN frames and https://datatracker.ietf.org/doc/html/rfc9000#section-19.8 also say > When a Stream Data field has a length of 0, the offset in the STREAM frame is the offset of the next byte that would be sent.
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This fixes a bug in connection level flow control accounting. When an empty STREAM frame without FIN is received, we calcuate the difference between the highest previously received offset and the frame's max_off and add that to connection level flow control. However, in
RecvBuf::write()we return early and we do not update the highest received offset. On subsequent frames, we count the same bytes against conn level flow control again.To fix this, we update the highest receive offset in RecvBuf::write(). The alternative would be to ignore such frames, but I think updating the high water mark is the right choice: It mimmicks what we do for empty FIN frames and https://datatracker.ietf.org/doc/html/rfc9000#section-19.8 also says