fix: reframe request body forwarded upstream in serverless plugins - #13798
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shreemaan-abhishek wants to merge 3 commits into
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fix: reframe request body forwarded upstream in serverless plugins#13798shreemaan-abhishek wants to merge 3 commits into
shreemaan-abhishek wants to merge 3 commits into
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The openfunction, aws-lambda and azure-functions plugins share generic-upstream.lua, which forwarded every inbound client header verbatim, including Transfer-Encoding, while supplying the request body already de-chunked by nginx. resty.http then kept Transfer-Encoding: chunked and wrote the unframed body raw, so the upstream request advertised chunked framing over a body that had none, letting the upstream misread the message length. Drop transfer-encoding and content-length before forwarding so the http client reframes the body with a correct Content-Length. Adds an end-to-end test that a chunked client body reaches the upstream reframed.
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AlinsRan
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Aug 11, 2026
…est-smuggling # Conflicts: # apisix/plugins/serverless/generic-upstream.lua
nic-6443
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AlinsRan
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nic-6443
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Description
The
openfunction,aws-lambdaandazure-functionsplugins shareapisix/plugins/serverless/generic-upstream.lua. It forwarded every inbound client header verbatim, includingTransfer-Encoding, while supplying the request body already de-chunked by nginx (ngx.req.get_body_data()).resty.httpthen keepsTransfer-Encoding: chunked, dropsContent-Length, and writes the now-unframed body raw without re-chunking. The forwarded upstream request advertised chunked framing over a body that had none, so a keep-alive upstream could misread where the message ends.Fix: strip the client's
Transfer-EncodingandContent-Lengthbefore forwarding, so the HTTP client recomputes a correctContent-Lengthfrom the actual body and never emits chunked framing over an unframed body. The strip runs before each plugin's request processor, soaws-lambdaSigV4 signs a clean header set.Added an end-to-end case in
t/plugin/aws-lambda.t: a chunked client request through the plugin, asserting the upstream receives a reframed body with a correctContent-Lengthand noTransfer-Encoding.Checklist