Mercurial > hg > nginx
view src/http/v2/ngx_http_v2_module.c @ 9300:5be23505292b
SSI: fixed incorrect or duplicate stub output.
Following 3518:eb3aaf8bd2a9 (0.8.37), r->request_output is only set
if there are data in the first buffer sent in the subrequest. As a
result, following the change mentioned this flag cannot be used to
prevent duplicate ngx_http_ssi_stub_output() calls, since it is not
set if there was already some output, but the first buffer was empty.
Still, when there are multiple subrequests, even an empty subrequest
response might be delayed by the postpone filter, leading to a second
call of ngx_http_ssi_stub_output() during finalization from
ngx_http_writer() the subreqest buffers are released by the postpone
filter. Since r->request_output is not set after the first call, this
resulted in duplicate stub output.
Additionally, checking only the first buffer might be wrong in some
unusual cases. For example, the first buffer might be empty if
$r->flush() is called before printing any data in the embedded Perl
module.
Depending on the postpone_output value and corresponding sizes, this
issue can result in either duplicate or unexpected stub output, or
"zero size buf in writer" alerts.
Following 8124:f5515e727656 (1.23.4), it became slightly easier to
reproduce the issue, as empty static files and empty cache items now
result in a response with an empty buffer. Before the change, an empty
proxied response can be used to reproduce the issue.
Fix is check all buffers and set r->request_output if any non-empty
buffers are sent. This ensures that all unusual cases of non-empty
responses are covered, and also that r->request_output will be set
after the first stub output, preventing duplicate output.
Reported by Jan Gassen.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Thu, 04 Jul 2024 17:41:28 +0300 |
parents | ea1f29c2010c |
children |
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/* * Copyright (C) Nginx, Inc. * Copyright (C) Valentin V. Bartenev */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> #include <ngx_http_v2_module.h> static ngx_int_t ngx_http_v2_add_variables(ngx_conf_t *cf); static ngx_int_t ngx_http_v2_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v, uintptr_t data); static ngx_int_t ngx_http_v2_module_init(ngx_cycle_t *cycle); static void *ngx_http_v2_create_main_conf(ngx_conf_t *cf); static char *ngx_http_v2_init_main_conf(ngx_conf_t *cf, void *conf); static void *ngx_http_v2_create_srv_conf(ngx_conf_t *cf); static char *ngx_http_v2_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child); static void *ngx_http_v2_create_loc_conf(ngx_conf_t *cf); static char *ngx_http_v2_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child); static char *ngx_http_v2_recv_buffer_size(ngx_conf_t *cf, void *post, void *data); static char *ngx_http_v2_pool_size(ngx_conf_t *cf, void *post, void *data); static char *ngx_http_v2_preread_size(ngx_conf_t *cf, void *post, void *data); static char *ngx_http_v2_streams_index_mask(ngx_conf_t *cf, void *post, void *data); static char *ngx_http_v2_chunk_size(ngx_conf_t *cf, void *post, void *data); static char *ngx_http_v2_obsolete(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_conf_deprecated_t ngx_http_v2_recv_timeout_deprecated = { ngx_conf_deprecated, "http2_recv_timeout", "client_header_timeout" }; static ngx_conf_deprecated_t ngx_http_v2_idle_timeout_deprecated = { ngx_conf_deprecated, "http2_idle_timeout", "keepalive_timeout" }; static ngx_conf_deprecated_t ngx_http_v2_max_requests_deprecated = { ngx_conf_deprecated, "http2_max_requests", "keepalive_requests" }; static ngx_conf_deprecated_t ngx_http_v2_max_field_size_deprecated = { ngx_conf_deprecated, "http2_max_field_size", "large_client_header_buffers" }; static ngx_conf_deprecated_t ngx_http_v2_max_header_size_deprecated = { ngx_conf_deprecated, "http2_max_header_size", "large_client_header_buffers" }; static ngx_conf_post_t ngx_http_v2_recv_buffer_size_post = { ngx_http_v2_recv_buffer_size }; static ngx_conf_post_t ngx_http_v2_pool_size_post = { ngx_http_v2_pool_size }; static ngx_conf_post_t ngx_http_v2_preread_size_post = { ngx_http_v2_preread_size }; static ngx_conf_post_t ngx_http_v2_streams_index_mask_post = { ngx_http_v2_streams_index_mask }; static ngx_conf_post_t ngx_http_v2_chunk_size_post = { ngx_http_v2_chunk_size }; static ngx_command_t ngx_http_v2_commands[] = { { ngx_string("http2"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_FLAG, ngx_conf_set_flag_slot, NGX_HTTP_SRV_CONF_OFFSET, offsetof(ngx_http_v2_srv_conf_t, enable), NULL }, { ngx_string("http2_recv_buffer_size"), NGX_HTTP_MAIN_CONF|NGX_CONF_TAKE1, ngx_conf_set_size_slot, NGX_HTTP_MAIN_CONF_OFFSET, offsetof(ngx_http_v2_main_conf_t, recv_buffer_size), &ngx_http_v2_recv_buffer_size_post }, { ngx_string("http2_pool_size"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1, ngx_conf_set_size_slot, NGX_HTTP_SRV_CONF_OFFSET, offsetof(ngx_http_v2_srv_conf_t, pool_size), &ngx_http_v2_pool_size_post }, { ngx_string("http2_max_concurrent_streams"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1, ngx_conf_set_num_slot, NGX_HTTP_SRV_CONF_OFFSET, offsetof(ngx_http_v2_srv_conf_t, concurrent_streams), NULL }, { ngx_string("http2_max_concurrent_pushes"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1, ngx_http_v2_obsolete, 0, 0, NULL }, { ngx_string("http2_max_requests"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1, ngx_http_v2_obsolete, 0, 0, &ngx_http_v2_max_requests_deprecated }, { ngx_string("http2_max_field_size"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1, ngx_http_v2_obsolete, 0, 0, &ngx_http_v2_max_field_size_deprecated }, { ngx_string("http2_max_header_size"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1, ngx_http_v2_obsolete, 0, 0, &ngx_http_v2_max_header_size_deprecated }, { ngx_string("http2_body_preread_size"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1, ngx_conf_set_size_slot, NGX_HTTP_SRV_CONF_OFFSET, offsetof(ngx_http_v2_srv_conf_t, preread_size), &ngx_http_v2_preread_size_post }, { ngx_string("http2_streams_index_size"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1, ngx_conf_set_num_slot, NGX_HTTP_SRV_CONF_OFFSET, offsetof(ngx_http_v2_srv_conf_t, streams_index_mask), &ngx_http_v2_streams_index_mask_post }, { ngx_string("http2_recv_timeout"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1, ngx_http_v2_obsolete, 0, 0, &ngx_http_v2_recv_timeout_deprecated }, { ngx_string("http2_idle_timeout"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1, ngx_http_v2_obsolete, 0, 0, &ngx_http_v2_idle_timeout_deprecated }, { ngx_string("http2_chunk_size"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_size_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_v2_loc_conf_t, chunk_size), &ngx_http_v2_chunk_size_post }, { ngx_string("http2_push_preload"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG, ngx_http_v2_obsolete, 0, 0, NULL }, { ngx_string("http2_push"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_http_v2_obsolete, 0, 0, NULL }, ngx_null_command }; static ngx_http_module_t ngx_http_v2_module_ctx = { ngx_http_v2_add_variables, /* preconfiguration */ NULL, /* postconfiguration */ ngx_http_v2_create_main_conf, /* create main configuration */ ngx_http_v2_init_main_conf, /* init main configuration */ ngx_http_v2_create_srv_conf, /* create server configuration */ ngx_http_v2_merge_srv_conf, /* merge server configuration */ ngx_http_v2_create_loc_conf, /* create location configuration */ ngx_http_v2_merge_loc_conf /* merge location configuration */ }; ngx_module_t ngx_http_v2_module = { NGX_MODULE_V1, &ngx_http_v2_module_ctx, /* module context */ ngx_http_v2_commands, /* module directives */ NGX_HTTP_MODULE, /* module type */ NULL, /* init master */ ngx_http_v2_module_init, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static ngx_http_variable_t ngx_http_v2_vars[] = { { ngx_string("http2"), NULL, ngx_http_v2_variable, 0, 0, 0 }, ngx_http_null_variable }; static ngx_int_t ngx_http_v2_add_variables(ngx_conf_t *cf) { ngx_http_variable_t *var, *v; for (v = ngx_http_v2_vars; v->name.len; v++) { var = ngx_http_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_http_v2_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v, uintptr_t data) { if (r->stream) { #if (NGX_HTTP_SSL) if (r->connection->ssl) { v->len = sizeof("h2") - 1; v->valid = 1; v->no_cacheable = 0; v->not_found = 0; v->data = (u_char *) "h2"; return NGX_OK; } #endif v->len = sizeof("h2c") - 1; v->valid = 1; v->no_cacheable = 0; v->not_found = 0; v->data = (u_char *) "h2c"; return NGX_OK; } *v = ngx_http_variable_null_value; return NGX_OK; } static ngx_int_t ngx_http_v2_module_init(ngx_cycle_t *cycle) { return NGX_OK; } static void * ngx_http_v2_create_main_conf(ngx_conf_t *cf) { ngx_http_v2_main_conf_t *h2mcf; h2mcf = ngx_pcalloc(cf->pool, sizeof(ngx_http_v2_main_conf_t)); if (h2mcf == NULL) { return NULL; } h2mcf->recv_buffer_size = NGX_CONF_UNSET_SIZE; return h2mcf; } static char * ngx_http_v2_init_main_conf(ngx_conf_t *cf, void *conf) { ngx_http_v2_main_conf_t *h2mcf = conf; ngx_conf_init_size_value(h2mcf->recv_buffer_size, 256 * 1024); return NGX_CONF_OK; } static void * ngx_http_v2_create_srv_conf(ngx_conf_t *cf) { ngx_http_v2_srv_conf_t *h2scf; h2scf = ngx_pcalloc(cf->pool, sizeof(ngx_http_v2_srv_conf_t)); if (h2scf == NULL) { return NULL; } h2scf->enable = NGX_CONF_UNSET; h2scf->pool_size = NGX_CONF_UNSET_SIZE; h2scf->concurrent_streams = NGX_CONF_UNSET_UINT; h2scf->preread_size = NGX_CONF_UNSET_SIZE; h2scf->streams_index_mask = NGX_CONF_UNSET_UINT; return h2scf; } static char * ngx_http_v2_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child) { ngx_http_v2_srv_conf_t *prev = parent; ngx_http_v2_srv_conf_t *conf = child; ngx_conf_merge_value(conf->enable, prev->enable, 0); ngx_conf_merge_size_value(conf->pool_size, prev->pool_size, 4096); ngx_conf_merge_uint_value(conf->concurrent_streams, prev->concurrent_streams, 128); ngx_conf_merge_size_value(conf->preread_size, prev->preread_size, 65536); ngx_conf_merge_uint_value(conf->streams_index_mask, prev->streams_index_mask, 32 - 1); return NGX_CONF_OK; } static void * ngx_http_v2_create_loc_conf(ngx_conf_t *cf) { ngx_http_v2_loc_conf_t *h2lcf; h2lcf = ngx_pcalloc(cf->pool, sizeof(ngx_http_v2_loc_conf_t)); if (h2lcf == NULL) { return NULL; } h2lcf->chunk_size = NGX_CONF_UNSET_SIZE; return h2lcf; } static char * ngx_http_v2_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child) { ngx_http_v2_loc_conf_t *prev = parent; ngx_http_v2_loc_conf_t *conf = child; ngx_conf_merge_size_value(conf->chunk_size, prev->chunk_size, 8 * 1024); return NGX_CONF_OK; } static char * ngx_http_v2_recv_buffer_size(ngx_conf_t *cf, void *post, void *data) { size_t *sp = data; if (*sp <= NGX_HTTP_V2_STATE_BUFFER_SIZE) { return "value is too small"; } return NGX_CONF_OK; } static char * ngx_http_v2_pool_size(ngx_conf_t *cf, void *post, void *data) { size_t *sp = data; if (*sp < NGX_MIN_POOL_SIZE) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "the pool size must be no less than %uz", NGX_MIN_POOL_SIZE); return NGX_CONF_ERROR; } if (*sp % NGX_POOL_ALIGNMENT) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "the pool size must be a multiple of %uz", NGX_POOL_ALIGNMENT); return NGX_CONF_ERROR; } return NGX_CONF_OK; } static char * ngx_http_v2_preread_size(ngx_conf_t *cf, void *post, void *data) { size_t *sp = data; if (*sp > NGX_HTTP_V2_MAX_WINDOW) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "the maximum body preread buffer size is %uz", NGX_HTTP_V2_MAX_WINDOW); return NGX_CONF_ERROR; } return NGX_CONF_OK; } static char * ngx_http_v2_streams_index_mask(ngx_conf_t *cf, void *post, void *data) { ngx_uint_t *np = data; ngx_uint_t mask; mask = *np - 1; if (*np == 0 || (*np & mask)) { return "must be a power of two"; } *np = mask; return NGX_CONF_OK; } static char * ngx_http_v2_chunk_size(ngx_conf_t *cf, void *post, void *data) { size_t *sp = data; if (*sp == 0) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "the http2 chunk size cannot be zero"); return NGX_CONF_ERROR; } if (*sp > NGX_HTTP_V2_MAX_FRAME_SIZE) { *sp = NGX_HTTP_V2_MAX_FRAME_SIZE; } return NGX_CONF_OK; } static char * ngx_http_v2_obsolete(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_conf_deprecated_t *d = cmd->post; if (d) { ngx_conf_log_error(NGX_LOG_WARN, cf, 0, "the \"%s\" directive is obsolete, " "use the \"%s\" directive instead", d->old_name, d->new_name); } else { ngx_conf_log_error(NGX_LOG_WARN, cf, 0, "the \"%V\" directive is obsolete, ignored", &cmd->name); } return NGX_CONF_OK; }