router: fix buffer overflow double-counting when decoding buffer and data are the same object#44346
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wdauchy wants to merge 5 commits intoenvoyproxy:mainfrom
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router: fix buffer overflow double-counting when decoding buffer and data are the same object#44346wdauchy wants to merge 5 commits intoenvoyproxy:mainfrom
wdauchy wants to merge 5 commits intoenvoyproxy:mainfrom
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…data are the same object When an upstream filter (e.g. envoy.filters.http.buffer) buffers the entire request body before passing it to the router, the shared buffered_request_data_ is passed directly as the `data` argument to decodeData(). The buffer overflow check computed `decodingBuffer().length() + data.length()`, but since both refer to the same object, this double-counted the payload size. This caused requests with body size between limit/2 and limit to incorrectly trigger buffer overflow, setting request_buffer_overflowed_ and cancelling internal redirects. The fix detects pointer equality between decodingBuffer() and data, mirroring the existing same-buffer guard in commonHandleBufferData(). tentative fix for envoyproxy#44128 Signed-off-by: William Dauchy <william.dauchy@datadoghq.com>
wbpcode
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Apr 9, 2026
Signed-off-by: William Dauchy <william.dauchy@datadoghq.com>
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/retest transients |
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Commit Message:
When an upstream filter (e.g. envoy.filters.http.buffer) buffers the entire request body before passing it to the router, the shared buffered_request_data_ is passed directly as the
dataargument to decodeData(). The buffer overflow check computeddecodingBuffer().length() + data.length(), but since both refer to the same object, this double-counted the payload size.This caused requests with body size between limit/2 and limit to incorrectly trigger buffer overflow, setting request_buffer_overflowed_ and cancelling internal redirects.
The fix detects pointer equality between decodingBuffer() and data, mirroring the existing same-buffer guard in commonHandleBufferData().
tentative fix for #44128
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