Fix HTTP/2 canceled stream cleanup timing#12673
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bneradt wants to merge 1 commit intoapache:masterfrom
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Fix HTTP/2 canceled stream cleanup timing#12673bneradt wants to merge 1 commit intoapache:masterfrom
bneradt wants to merge 1 commit intoapache:masterfrom
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When streams are canceled via RST_STREAM, the stream deletion now happens immediately before the next frame is processed. This prevents the race condition where new HEADERS frames are incorrectly refused because the stream count hasn't been decremented yet. Additionally, when streams are refused due to exceeding max_concurrent_streams, the header blocks are now properly decoded to maintain HPACK dynamic table synchronization per RFC 9113, and RST_STREAM with REFUSED_STREAM is sent instead of terminating the connection with COMPRESSION_ERROR. Fixes: apache#9179
maskit
reviewed
Dec 1, 2025
| // This prevents the race condition where HEADERS frames are incorrectly refused due to the | ||
| // stream count not being decremented yet. The destructor will handle the case where the stream | ||
| // has already been removed from the stream list. | ||
| this->delete_stream(stream); |
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Shouldn't we call THREAD_FREE(stream, http2StreamAllocator, this_ethread()); instead of calling these two, initiating_close and delete_stream?
maskit
reviewed
Dec 1, 2025
| "failed to create temporary stream for header decoding"); | ||
| } | ||
| free_stream_after_decoding = true; | ||
| reset_header_after_decoding = true; |
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Why don't you delete the stream here and return error that probably contains HTTP2_ERROR_REFUSED_STREAM?
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When streams are canceled via RST_STREAM, the stream deletion now happens immediately before the next frame is processed. This prevents the race condition where new HEADERS frames are incorrectly refused because the stream count hasn't been decremented yet. Additionally, when streams are refused due to exceeding max_concurrent_streams, the header blocks are now properly decoded to maintain HPACK dynamic table synchronization per RFC 9113, and RST_STREAM with REFUSED_STREAM is sent instead of terminating the connection with COMPRESSION_ERROR.
Fixes: #9179
I have run this on a machine taking production traffic and it ran fine.