Mercurial > hg > nginx
view src/stream/ngx_stream_return_module.c @ 7570:d6cf51af8a3d
HTTP/2: fixed possible alert about left open socket on shutdown.
This could happen when graceful shutdown configured by worker_shutdown_timeout
times out and is then followed by another timeout such as proxy_read_timeout.
In this case, the HEADERS frame is added to the output queue, but attempt to
send it fails (due to c->error forcibly set during graceful shutdown timeout).
This triggers request finalization which attempts to close the stream. But the
stream cannot be closed because there is a frame in the output queue, and the
connection cannot be finalized. This leaves the connection open without any
timer events leading to alert.
The fix is to post write event when sending output queue fails on c->error.
That will finalize the connection.
author | Ruslan Ermilov <ru@nginx.com> |
---|---|
date | Mon, 23 Sep 2019 15:45:32 +0300 |
parents | 56fc55e32f23 |
children |
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/* * Copyright (C) Roman Arutyunyan * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_stream.h> typedef struct { ngx_stream_complex_value_t text; } ngx_stream_return_srv_conf_t; typedef struct { ngx_chain_t *out; } ngx_stream_return_ctx_t; static void ngx_stream_return_handler(ngx_stream_session_t *s); static void ngx_stream_return_write_handler(ngx_event_t *ev); static void *ngx_stream_return_create_srv_conf(ngx_conf_t *cf); static char *ngx_stream_return(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_command_t ngx_stream_return_commands[] = { { ngx_string("return"), NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1, ngx_stream_return, NGX_STREAM_SRV_CONF_OFFSET, 0, NULL }, ngx_null_command }; static ngx_stream_module_t ngx_stream_return_module_ctx = { NULL, /* preconfiguration */ NULL, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ ngx_stream_return_create_srv_conf, /* create server configuration */ NULL /* merge server configuration */ }; ngx_module_t ngx_stream_return_module = { NGX_MODULE_V1, &ngx_stream_return_module_ctx, /* module context */ ngx_stream_return_commands, /* module directives */ NGX_STREAM_MODULE, /* module type */ NULL, /* init master */ NULL, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static void ngx_stream_return_handler(ngx_stream_session_t *s) { ngx_str_t text; ngx_buf_t *b; ngx_connection_t *c; ngx_stream_return_ctx_t *ctx; ngx_stream_return_srv_conf_t *rscf; c = s->connection; c->log->action = "returning text"; rscf = ngx_stream_get_module_srv_conf(s, ngx_stream_return_module); if (ngx_stream_complex_value(s, &rscf->text, &text) != NGX_OK) { ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR); return; } ngx_log_debug1(NGX_LOG_DEBUG_STREAM, c->log, 0, "stream return text: \"%V\"", &text); if (text.len == 0) { ngx_stream_finalize_session(s, NGX_STREAM_OK); return; } ctx = ngx_pcalloc(c->pool, sizeof(ngx_stream_return_ctx_t)); if (ctx == NULL) { ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR); return; } ngx_stream_set_ctx(s, ctx, ngx_stream_return_module); b = ngx_calloc_buf(c->pool); if (b == NULL) { ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR); return; } b->memory = 1; b->pos = text.data; b->last = text.data + text.len; b->last_buf = 1; ctx->out = ngx_alloc_chain_link(c->pool); if (ctx->out == NULL) { ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR); return; } ctx->out->buf = b; ctx->out->next = NULL; c->write->handler = ngx_stream_return_write_handler; ngx_stream_return_write_handler(c->write); } static void ngx_stream_return_write_handler(ngx_event_t *ev) { ngx_connection_t *c; ngx_stream_session_t *s; ngx_stream_return_ctx_t *ctx; c = ev->data; s = c->data; if (ev->timedout) { ngx_connection_error(c, NGX_ETIMEDOUT, "connection timed out"); ngx_stream_finalize_session(s, NGX_STREAM_OK); return; } ctx = ngx_stream_get_module_ctx(s, ngx_stream_return_module); if (ngx_stream_top_filter(s, ctx->out, 1) == NGX_ERROR) { ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR); return; } ctx->out = NULL; if (!c->buffered) { ngx_log_debug0(NGX_LOG_DEBUG_STREAM, c->log, 0, "stream return done sending"); ngx_stream_finalize_session(s, NGX_STREAM_OK); return; } if (ngx_handle_write_event(ev, 0) != NGX_OK) { ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR); return; } ngx_add_timer(ev, 5000); } static void * ngx_stream_return_create_srv_conf(ngx_conf_t *cf) { ngx_stream_return_srv_conf_t *conf; conf = ngx_pcalloc(cf->pool, sizeof(ngx_stream_return_srv_conf_t)); if (conf == NULL) { return NULL; } return conf; } static char * ngx_stream_return(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_stream_return_srv_conf_t *rscf = conf; ngx_str_t *value; ngx_stream_core_srv_conf_t *cscf; ngx_stream_compile_complex_value_t ccv; if (rscf->text.value.data) { return "is duplicate"; } value = cf->args->elts; ngx_memzero(&ccv, sizeof(ngx_stream_compile_complex_value_t)); ccv.cf = cf; ccv.value = &value[1]; ccv.complex_value = &rscf->text; if (ngx_stream_compile_complex_value(&ccv) != NGX_OK) { return NGX_CONF_ERROR; } cscf = ngx_stream_conf_get_module_srv_conf(cf, ngx_stream_core_module); cscf->handler = ngx_stream_return_handler; return NGX_CONF_OK; }