id summary reporter owner description type status priority milestone component version resolution keywords cc uname nginx_version 350 http proxy module: wrong Content-Length shared between main request and subrequests Sergey Kandaurov "lanshun zhou reports: Nginx uses a variable ""$proxy_internal_body_length"" for the ""Content-Length"" header in http proxy module, which is cacheable and shared between the main request and all subrequests by default. Although ctx->internal_body_length is calculated for each request/subrequest, the string format is cached after the first generation, and this may be wrong for other subrequests. The following simple config can reproduce the problem, where xxxxx is a place that can receive post data. curl --data-binary ""xxxxxxxxxxxxxxx"" localhost/test.html will cause the client hang. location = /test.html { add_after_body /vpost; proxy_pass http://xxxxx; } location /vpost { proxy_set_body ""in vpost""; proxy_pass http://xxxxx; } Reference: http://mailman.nginx.org/pipermail/nginx-devel/2013-May/003669.html diff -r 0ebf6344db81 src/http/modules/ngx_http_proxy_module.c --- a/src/http/modules/ngx_http_proxy_module.c Fri Apr 26 11:11:03 2013 +0800 +++ b/src/http/modules/ngx_http_proxy_module.c Fri May 03 10:52:41 2013 +0800 @@ -615,7 +615,8 @@ #endif { ngx_string(""proxy_internal_body_length""), NULL, - ngx_http_proxy_internal_body_length_variable, 0, NGX_HTTP_VAR_NOHASH, 0 }, + ngx_http_proxy_internal_body_length_variable, 0, + NGX_HTTP_VAR_NOCACHEABLE|NGX_HTTP_VAR_NOHASH, 0 }, { ngx_null_string, NULL, NULL, 0, 0, 0 } }; " defect new minor nginx-module 1.3.x n/a