Nicolfo opened a new issue, #13694: URL: https://github.com/apache/apisix/issues/13694
### Current Behavior When `nginx_config.http.client_max_body_size` is set to `0` (documented as "no limit", and also the default value), APISIX rejects **every** request that uses `Transfer-Encoding: chunked` with `413 Request Entity Too Large` — regardless of the actual body size. Even a 1-byte chunked body is rejected immediately. Requests carrying a `Content-Length` header are handled correctly: with `client_max_body_size: 0` they pass through at any size (tested up to 300 MB). This deviates from stock nginx semantics, where `client_max_body_size 0;` disables the body size check for both sized and chunked requests. Real-world impact: `docker push` streams blob uploads (`PATCH /v2/<name>/blobs/uploads/<uuid>`) with chunked transfer encoding, so any container registry (e.g. Harbor) behind APISIX 3.17 with the default body size setting fails with 413 on every push. The apisix-helm-chart 2.16.0 renders `client_max_body_size: 0` by default, so a default Helm installation is affected out of the box. Setting an explicit non-zero value (e.g. `1g`) restores correct behavior for chunked requests. ### Expected Behavior `client_max_body_size: 0` should mean "unlimited" for chunked requests as well, consistent with the `Content-Length` case and with nginx's documented behavior. ### Error Logs Nothing is written to the error log. The access log shows the 413 being generated by APISIX itself with no upstream involved: ``` 172.17.0.1 - - [13/Jul/2026:09:20:11 +0000] 127.0.0.1:19080 "POST /anything HTTP/1.1" 413 255 0.000 "-" "curl/8.7.1" - - - "http://127.0.0.1:19080"; ``` Response: ``` < HTTP/1.1 413 Request Entity Too Large < Server: APISIX/3.17.0 ``` ### Steps to Reproduce 1. `config.yaml` (standalone mode, minimal): ```yaml deployment: role: data_plane role_data_plane: config_provider: yaml apisix: node_listen: 9080 nginx_config: http: client_max_body_size: 0 ``` 2. `apisix.yaml` (any upstream works; it is never reached for chunked requests): ```yaml routes: - uri: /* upstream: nodes: "127.0.0.1:9180": 1 type: roundrobin #END ``` 3. Run APISIX: ```bash docker run -d --name apisix-413 -p 19080:9080 \ -v $PWD/config.yaml:/usr/local/apisix/conf/config.yaml:ro \ -v $PWD/apisix.yaml:/usr/local/apisix/conf/apisix.yaml:ro \ apache/apisix:3.17.0-debian ``` 4. Send the same 5-byte body with and without chunked encoding: ```bash printf 'hello' > body.bin # Content-Length request -> passes through (502 because the dummy upstream is dead) curl -s -o /dev/null -w '%{http_code}\n' -X POST \ --data-binary @body.bin http://127.0.0.1:19080/anything # => 502 # chunked request -> rejected by APISIX before reaching the upstream curl -s --http1.1 -o /dev/null -w '%{http_code}\n' -X POST \ -H 'Transfer-Encoding: chunked' --data-binary @body.bin http://127.0.0.1:19080/anything # => 413 ``` 5. Change `client_max_body_size` to `1g` and restart: the chunked request now returns 502 (passes through) as expected. Notes: - Removing `nginx_config.http.client_max_body_size` entirely reproduces the same 413, so the default configuration is affected too. - Reproduced over both HTTP/1.1 and HTTP/2 (TLS), any method (GET/POST/PATCH), any route. ### Environment - APISIX version: 3.17.0 (official image `apache/apisix:3.17.0-debian`, also deployed via apisix-helm-chart 2.16.0) - Operating system: Docker 29.4.0 on Windows 11 (also reproduced on Kubernetes/containerd on Linux) - OpenResty / Nginx version: bundled with the 3.17.0 image (`Server: APISIX/3.17.0`) - etcd version: n/a (standalone mode; also reproduced with etcd 3.5 in the Helm deployment) -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
