Mercurial > hg > nginx-quic
view src/stream/ngx_stream_upstream.c @ 8867:5119c8150478
Fixed runtime handling of systems without EPOLLRDHUP support.
In 7583:efd71d49bde0 (nginx 1.17.5) along with introduction of the
ioctl(FIONREAD) support proper handling of systems without EPOLLRDHUP
support in the kernel (but with EPOLLRDHUP in headers) was broken.
Before the change, rev->available was never set to 0 unless
ngx_use_epoll_rdhup was also set (that is, runtime test for EPOLLRDHUP
introduced in 6536:f7849bfb6d21 succeeded). After the change,
rev->available might reach 0 on systems without runtime EPOLLRDHUP
support, stopping further reading in ngx_readv_chain() and ngx_unix_recv().
And, if EOF happened to be already reported along with the last event,
it is not reported again by epoll_wait(), leading to connection hangs
and timeouts on such systems.
This affects Linux kernels before 2.6.17 if nginx was compiled
with newer headers, and, more importantly, emulation layers, such as
DigitalOcean's App Platform's / gVisor's epoll emulation layer.
Fix is to explicitly check ngx_use_epoll_rdhup before the corresponding
rev->pending_eof tests in ngx_readv_chain() and ngx_unix_recv().
author | Marcus Ball <marcus.ball@live.com> |
---|---|
date | Mon, 30 May 2022 02:38:07 +0300 |
parents | 860d3907da1c |
children |
line wrap: on
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_stream.h> static ngx_int_t ngx_stream_upstream_add_variables(ngx_conf_t *cf); static ngx_int_t ngx_stream_upstream_addr_variable(ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data); static ngx_int_t ngx_stream_upstream_response_time_variable( ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data); static ngx_int_t ngx_stream_upstream_bytes_variable(ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data); static char *ngx_stream_upstream(ngx_conf_t *cf, ngx_command_t *cmd, void *dummy); static char *ngx_stream_upstream_server(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static void *ngx_stream_upstream_create_main_conf(ngx_conf_t *cf); static char *ngx_stream_upstream_init_main_conf(ngx_conf_t *cf, void *conf); static ngx_command_t ngx_stream_upstream_commands[] = { { ngx_string("upstream"), NGX_STREAM_MAIN_CONF|NGX_CONF_BLOCK|NGX_CONF_TAKE1, ngx_stream_upstream, 0, 0, NULL }, { ngx_string("server"), NGX_STREAM_UPS_CONF|NGX_CONF_1MORE, ngx_stream_upstream_server, NGX_STREAM_SRV_CONF_OFFSET, 0, NULL }, ngx_null_command }; static ngx_stream_module_t ngx_stream_upstream_module_ctx = { ngx_stream_upstream_add_variables, /* preconfiguration */ NULL, /* postconfiguration */ ngx_stream_upstream_create_main_conf, /* create main configuration */ ngx_stream_upstream_init_main_conf, /* init main configuration */ NULL, /* create server configuration */ NULL /* merge server configuration */ }; ngx_module_t ngx_stream_upstream_module = { NGX_MODULE_V1, &ngx_stream_upstream_module_ctx, /* module context */ ngx_stream_upstream_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 ngx_stream_variable_t ngx_stream_upstream_vars[] = { { ngx_string("upstream_addr"), NULL, ngx_stream_upstream_addr_variable, 0, NGX_STREAM_VAR_NOCACHEABLE, 0 }, { ngx_string("upstream_bytes_sent"), NULL, ngx_stream_upstream_bytes_variable, 0, NGX_STREAM_VAR_NOCACHEABLE, 0 }, { ngx_string("upstream_connect_time"), NULL, ngx_stream_upstream_response_time_variable, 2, NGX_STREAM_VAR_NOCACHEABLE, 0 }, { ngx_string("upstream_first_byte_time"), NULL, ngx_stream_upstream_response_time_variable, 1, NGX_STREAM_VAR_NOCACHEABLE, 0 }, { ngx_string("upstream_session_time"), NULL, ngx_stream_upstream_response_time_variable, 0, NGX_STREAM_VAR_NOCACHEABLE, 0 }, { ngx_string("upstream_bytes_received"), NULL, ngx_stream_upstream_bytes_variable, 1, NGX_STREAM_VAR_NOCACHEABLE, 0 }, ngx_stream_null_variable }; static ngx_int_t ngx_stream_upstream_add_variables(ngx_conf_t *cf) { ngx_stream_variable_t *var, *v; for (v = ngx_stream_upstream_vars; v->name.len; v++) { var = ngx_stream_add_variable(cf, &v->name, v->flags); if (var == NULL) { return NGX_ERROR; } var->get_handler = v->get_handler; var->data = v->data; } return NGX_OK; } static ngx_int_t ngx_stream_upstream_addr_variable(ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data) { u_char *p; size_t len; ngx_uint_t i; ngx_stream_upstream_state_t *state; v->valid = 1; v->no_cacheable = 0; v->not_found = 0; if (s->upstream_states == NULL || s->upstream_states->nelts == 0) { v->not_found = 1; return NGX_OK; } len = 0; state = s->upstream_states->elts; for (i = 0; i < s->upstream_states->nelts; i++) { if (state[i].peer) { len += state[i].peer->len; } len += 2; } p = ngx_pnalloc(s->connection->pool, len); if (p == NULL) { return NGX_ERROR; } v->data = p; i = 0; for ( ;; ) { if (state[i].peer) { p = ngx_cpymem(p, state[i].peer->data, state[i].peer->len); } if (++i == s->upstream_states->nelts) { break; } *p++ = ','; *p++ = ' '; } v->len = p - v->data; return NGX_OK; } static ngx_int_t ngx_stream_upstream_bytes_variable(ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data) { u_char *p; size_t len; ngx_uint_t i; ngx_stream_upstream_state_t *state; v->valid = 1; v->no_cacheable = 0; v->not_found = 0; if (s->upstream_states == NULL || s->upstream_states->nelts == 0) { v->not_found = 1; return NGX_OK; } len = s->upstream_states->nelts * (NGX_OFF_T_LEN + 2); p = ngx_pnalloc(s->connection->pool, len); if (p == NULL) { return NGX_ERROR; } v->data = p; i = 0; state = s->upstream_states->elts; for ( ;; ) { if (data == 1) { p = ngx_sprintf(p, "%O", state[i].bytes_received); } else { p = ngx_sprintf(p, "%O", state[i].bytes_sent); } if (++i == s->upstream_states->nelts) { break; } *p++ = ','; *p++ = ' '; } v->len = p - v->data; return NGX_OK; } static ngx_int_t ngx_stream_upstream_response_time_variable(ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data) { u_char *p; size_t len; ngx_uint_t i; ngx_msec_int_t ms; ngx_stream_upstream_state_t *state; v->valid = 1; v->no_cacheable = 0; v->not_found = 0; if (s->upstream_states == NULL || s->upstream_states->nelts == 0) { v->not_found = 1; return NGX_OK; } len = s->upstream_states->nelts * (NGX_TIME_T_LEN + 4 + 2); p = ngx_pnalloc(s->connection->pool, len); if (p == NULL) { return NGX_ERROR; } v->data = p; i = 0; state = s->upstream_states->elts; for ( ;; ) { if (data == 1) { ms = state[i].first_byte_time; } else if (data == 2) { ms = state[i].connect_time; } else { ms = state[i].response_time; } if (ms != -1) { ms = ngx_max(ms, 0); p = ngx_sprintf(p, "%T.%03M", (time_t) ms / 1000, ms % 1000); } else { *p++ = '-'; } if (++i == s->upstream_states->nelts) { break; } *p++ = ','; *p++ = ' '; } v->len = p - v->data; return NGX_OK; } static char * ngx_stream_upstream(ngx_conf_t *cf, ngx_command_t *cmd, void *dummy) { char *rv; void *mconf; ngx_str_t *value; ngx_url_t u; ngx_uint_t m; ngx_conf_t pcf; ngx_stream_module_t *module; ngx_stream_conf_ctx_t *ctx, *stream_ctx; ngx_stream_upstream_srv_conf_t *uscf; ngx_memzero(&u, sizeof(ngx_url_t)); value = cf->args->elts; u.host = value[1]; u.no_resolve = 1; u.no_port = 1; uscf = ngx_stream_upstream_add(cf, &u, NGX_STREAM_UPSTREAM_CREATE |NGX_STREAM_UPSTREAM_WEIGHT |NGX_STREAM_UPSTREAM_MAX_CONNS |NGX_STREAM_UPSTREAM_MAX_FAILS |NGX_STREAM_UPSTREAM_FAIL_TIMEOUT |NGX_STREAM_UPSTREAM_DOWN |NGX_STREAM_UPSTREAM_BACKUP); if (uscf == NULL) { return NGX_CONF_ERROR; } ctx = ngx_pcalloc(cf->pool, sizeof(ngx_stream_conf_ctx_t)); if (ctx == NULL) { return NGX_CONF_ERROR; } stream_ctx = cf->ctx; ctx->main_conf = stream_ctx->main_conf; /* the upstream{}'s srv_conf */ ctx->srv_conf = ngx_pcalloc(cf->pool, sizeof(void *) * ngx_stream_max_module); if (ctx->srv_conf == NULL) { return NGX_CONF_ERROR; } ctx->srv_conf[ngx_stream_upstream_module.ctx_index] = uscf; uscf->srv_conf = ctx->srv_conf; for (m = 0; cf->cycle->modules[m]; m++) { if (cf->cycle->modules[m]->type != NGX_STREAM_MODULE) { continue; } module = cf->cycle->modules[m]->ctx; if (module->create_srv_conf) { mconf = module->create_srv_conf(cf); if (mconf == NULL) { return NGX_CONF_ERROR; } ctx->srv_conf[cf->cycle->modules[m]->ctx_index] = mconf; } } uscf->servers = ngx_array_create(cf->pool, 4, sizeof(ngx_stream_upstream_server_t)); if (uscf->servers == NULL) { return NGX_CONF_ERROR; } /* parse inside upstream{} */ pcf = *cf; cf->ctx = ctx; cf->cmd_type = NGX_STREAM_UPS_CONF; rv = ngx_conf_parse(cf, NULL); *cf = pcf; if (rv != NGX_CONF_OK) { return rv; } if (uscf->servers->nelts == 0) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "no servers are inside upstream"); return NGX_CONF_ERROR; } return rv; } static char * ngx_stream_upstream_server(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_stream_upstream_srv_conf_t *uscf = conf; time_t fail_timeout; ngx_str_t *value, s; ngx_url_t u; ngx_int_t weight, max_conns, max_fails; ngx_uint_t i; ngx_stream_upstream_server_t *us; us = ngx_array_push(uscf->servers); if (us == NULL) { return NGX_CONF_ERROR; } ngx_memzero(us, sizeof(ngx_stream_upstream_server_t)); value = cf->args->elts; weight = 1; max_conns = 0; max_fails = 1; fail_timeout = 10; for (i = 2; i < cf->args->nelts; i++) { if (ngx_strncmp(value[i].data, "weight=", 7) == 0) { if (!(uscf->flags & NGX_STREAM_UPSTREAM_WEIGHT)) { goto not_supported; } weight = ngx_atoi(&value[i].data[7], value[i].len - 7); if (weight == NGX_ERROR || weight == 0) { goto invalid; } continue; } if (ngx_strncmp(value[i].data, "max_conns=", 10) == 0) { if (!(uscf->flags & NGX_STREAM_UPSTREAM_MAX_CONNS)) { goto not_supported; } max_conns = ngx_atoi(&value[i].data[10], value[i].len - 10); if (max_conns == NGX_ERROR) { goto invalid; } continue; } if (ngx_strncmp(value[i].data, "max_fails=", 10) == 0) { if (!(uscf->flags & NGX_STREAM_UPSTREAM_MAX_FAILS)) { goto not_supported; } max_fails = ngx_atoi(&value[i].data[10], value[i].len - 10); if (max_fails == NGX_ERROR) { goto invalid; } continue; } if (ngx_strncmp(value[i].data, "fail_timeout=", 13) == 0) { if (!(uscf->flags & NGX_STREAM_UPSTREAM_FAIL_TIMEOUT)) { goto not_supported; } s.len = value[i].len - 13; s.data = &value[i].data[13]; fail_timeout = ngx_parse_time(&s, 1); if (fail_timeout == (time_t) NGX_ERROR) { goto invalid; } continue; } if (ngx_strcmp(value[i].data, "backup") == 0) { if (!(uscf->flags & NGX_STREAM_UPSTREAM_BACKUP)) { goto not_supported; } us->backup = 1; continue; } if (ngx_strcmp(value[i].data, "down") == 0) { if (!(uscf->flags & NGX_STREAM_UPSTREAM_DOWN)) { goto not_supported; } us->down = 1; continue; } goto invalid; } ngx_memzero(&u, sizeof(ngx_url_t)); u.url = value[1]; if (ngx_parse_url(cf->pool, &u) != NGX_OK) { if (u.err) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "%s in upstream \"%V\"", u.err, &u.url); } return NGX_CONF_ERROR; } if (u.no_port) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "no port in upstream \"%V\"", &u.url); return NGX_CONF_ERROR; } us->name = u.url; us->addrs = u.addrs; us->naddrs = u.naddrs; us->weight = weight; us->max_conns = max_conns; us->max_fails = max_fails; us->fail_timeout = fail_timeout; return NGX_CONF_OK; invalid: ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid parameter \"%V\"", &value[i]); return NGX_CONF_ERROR; not_supported: ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "balancing method does not support parameter \"%V\"", &value[i]); return NGX_CONF_ERROR; } ngx_stream_upstream_srv_conf_t * ngx_stream_upstream_add(ngx_conf_t *cf, ngx_url_t *u, ngx_uint_t flags) { ngx_uint_t i; ngx_stream_upstream_server_t *us; ngx_stream_upstream_srv_conf_t *uscf, **uscfp; ngx_stream_upstream_main_conf_t *umcf; if (!(flags & NGX_STREAM_UPSTREAM_CREATE)) { if (ngx_parse_url(cf->pool, u) != NGX_OK) { if (u->err) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "%s in upstream \"%V\"", u->err, &u->url); } return NULL; } } umcf = ngx_stream_conf_get_module_main_conf(cf, ngx_stream_upstream_module); uscfp = umcf->upstreams.elts; for (i = 0; i < umcf->upstreams.nelts; i++) { if (uscfp[i]->host.len != u->host.len || ngx_strncasecmp(uscfp[i]->host.data, u->host.data, u->host.len) != 0) { continue; } if ((flags & NGX_STREAM_UPSTREAM_CREATE) && (uscfp[i]->flags & NGX_STREAM_UPSTREAM_CREATE)) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate upstream \"%V\"", &u->host); return NULL; } if ((uscfp[i]->flags & NGX_STREAM_UPSTREAM_CREATE) && !u->no_port) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "upstream \"%V\" may not have port %d", &u->host, u->port); return NULL; } if ((flags & NGX_STREAM_UPSTREAM_CREATE) && !uscfp[i]->no_port) { ngx_log_error(NGX_LOG_EMERG, cf->log, 0, "upstream \"%V\" may not have port %d in %s:%ui", &u->host, uscfp[i]->port, uscfp[i]->file_name, uscfp[i]->line); return NULL; } if (uscfp[i]->port != u->port) { continue; } if (flags & NGX_STREAM_UPSTREAM_CREATE) { uscfp[i]->flags = flags; } return uscfp[i]; } uscf = ngx_pcalloc(cf->pool, sizeof(ngx_stream_upstream_srv_conf_t)); if (uscf == NULL) { return NULL; } uscf->flags = flags; uscf->host = u->host; uscf->file_name = cf->conf_file->file.name.data; uscf->line = cf->conf_file->line; uscf->port = u->port; uscf->no_port = u->no_port; if (u->naddrs == 1 && (u->port || u->family == AF_UNIX)) { uscf->servers = ngx_array_create(cf->pool, 1, sizeof(ngx_stream_upstream_server_t)); if (uscf->servers == NULL) { return NULL; } us = ngx_array_push(uscf->servers); if (us == NULL) { return NULL; } ngx_memzero(us, sizeof(ngx_stream_upstream_server_t)); us->addrs = u->addrs; us->naddrs = 1; } uscfp = ngx_array_push(&umcf->upstreams); if (uscfp == NULL) { return NULL; } *uscfp = uscf; return uscf; } static void * ngx_stream_upstream_create_main_conf(ngx_conf_t *cf) { ngx_stream_upstream_main_conf_t *umcf; umcf = ngx_pcalloc(cf->pool, sizeof(ngx_stream_upstream_main_conf_t)); if (umcf == NULL) { return NULL; } if (ngx_array_init(&umcf->upstreams, cf->pool, 4, sizeof(ngx_stream_upstream_srv_conf_t *)) != NGX_OK) { return NULL; } return umcf; } static char * ngx_stream_upstream_init_main_conf(ngx_conf_t *cf, void *conf) { ngx_stream_upstream_main_conf_t *umcf = conf; ngx_uint_t i; ngx_stream_upstream_init_pt init; ngx_stream_upstream_srv_conf_t **uscfp; uscfp = umcf->upstreams.elts; for (i = 0; i < umcf->upstreams.nelts; i++) { init = uscfp[i]->peer.init_upstream ? uscfp[i]->peer.init_upstream : ngx_stream_upstream_init_round_robin; if (init(cf, uscfp[i]) != NGX_OK) { return NGX_CONF_ERROR; } } return NGX_CONF_OK; }