Mercurial > hg > nginx
view src/stream/ngx_stream_handler.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 | 113e2438dbd4 |
children |
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/* * Copyright (C) Roman Arutyunyan * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #include <ngx_stream.h> static void ngx_stream_log_session(ngx_stream_session_t *s); static void ngx_stream_close_connection(ngx_connection_t *c); static u_char *ngx_stream_log_error(ngx_log_t *log, u_char *buf, size_t len); static void ngx_stream_proxy_protocol_handler(ngx_event_t *rev); void ngx_stream_init_connection(ngx_connection_t *c) { u_char text[NGX_SOCKADDR_STRLEN]; size_t len; ngx_uint_t i; ngx_time_t *tp; ngx_event_t *rev; struct sockaddr *sa; ngx_stream_port_t *port; struct sockaddr_in *sin; ngx_stream_in_addr_t *addr; ngx_stream_session_t *s; ngx_stream_addr_conf_t *addr_conf; #if (NGX_HAVE_INET6) struct sockaddr_in6 *sin6; ngx_stream_in6_addr_t *addr6; #endif ngx_stream_core_srv_conf_t *cscf; ngx_stream_core_main_conf_t *cmcf; /* find the server configuration for the address:port */ port = c->listening->servers; if (port->naddrs > 1) { /* * There are several addresses on this port and one of them * is the "*:port" wildcard so getsockname() is needed to determine * the server address. * * AcceptEx() and recvmsg() already gave this address. */ if (ngx_connection_local_sockaddr(c, NULL, 0) != NGX_OK) { ngx_stream_close_connection(c); return; } sa = c->local_sockaddr; switch (sa->sa_family) { #if (NGX_HAVE_INET6) case AF_INET6: sin6 = (struct sockaddr_in6 *) sa; addr6 = port->addrs; /* the last address is "*" */ for (i = 0; i < port->naddrs - 1; i++) { if (ngx_memcmp(&addr6[i].addr6, &sin6->sin6_addr, 16) == 0) { break; } } addr_conf = &addr6[i].conf; break; #endif default: /* AF_INET */ sin = (struct sockaddr_in *) sa; addr = port->addrs; /* the last address is "*" */ for (i = 0; i < port->naddrs - 1; i++) { if (addr[i].addr == sin->sin_addr.s_addr) { break; } } addr_conf = &addr[i].conf; break; } } else { switch (c->local_sockaddr->sa_family) { #if (NGX_HAVE_INET6) case AF_INET6: addr6 = port->addrs; addr_conf = &addr6[0].conf; break; #endif default: /* AF_INET */ addr = port->addrs; addr_conf = &addr[0].conf; break; } } s = ngx_pcalloc(c->pool, sizeof(ngx_stream_session_t)); if (s == NULL) { ngx_stream_close_connection(c); return; } s->signature = NGX_STREAM_MODULE; s->main_conf = addr_conf->ctx->main_conf; s->srv_conf = addr_conf->ctx->srv_conf; #if (NGX_STREAM_SSL) s->ssl = addr_conf->ssl; #endif if (c->buffer) { s->received += c->buffer->last - c->buffer->pos; } s->connection = c; c->data = s; cscf = ngx_stream_get_module_srv_conf(s, ngx_stream_core_module); ngx_set_connection_log(c, cscf->error_log); len = ngx_sock_ntop(c->sockaddr, c->socklen, text, NGX_SOCKADDR_STRLEN, 1); ngx_log_error(NGX_LOG_INFO, c->log, 0, "*%uA %sclient %*s connected to %V", c->number, c->type == SOCK_DGRAM ? "udp " : "", len, text, &addr_conf->addr_text); c->log->connection = c->number; c->log->handler = ngx_stream_log_error; c->log->data = s; c->log->action = "initializing session"; c->log_error = NGX_ERROR_INFO; s->ctx = ngx_pcalloc(c->pool, sizeof(void *) * ngx_stream_max_module); if (s->ctx == NULL) { ngx_stream_close_connection(c); return; } cmcf = ngx_stream_get_module_main_conf(s, ngx_stream_core_module); s->variables = ngx_pcalloc(s->connection->pool, cmcf->variables.nelts * sizeof(ngx_stream_variable_value_t)); if (s->variables == NULL) { ngx_stream_close_connection(c); return; } tp = ngx_timeofday(); s->start_sec = tp->sec; s->start_msec = tp->msec; rev = c->read; rev->handler = ngx_stream_session_handler; if (addr_conf->proxy_protocol) { c->log->action = "reading PROXY protocol"; rev->handler = ngx_stream_proxy_protocol_handler; if (!rev->ready) { ngx_add_timer(rev, cscf->proxy_protocol_timeout); if (ngx_handle_read_event(rev, 0) != NGX_OK) { ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR); } return; } } if (ngx_use_accept_mutex) { ngx_post_event(rev, &ngx_posted_events); return; } rev->handler(rev); } static void ngx_stream_proxy_protocol_handler(ngx_event_t *rev) { u_char *p, buf[NGX_PROXY_PROTOCOL_MAX_HEADER]; size_t size; ssize_t n; ngx_err_t err; ngx_connection_t *c; ngx_stream_session_t *s; ngx_stream_core_srv_conf_t *cscf; c = rev->data; s = c->data; ngx_log_debug0(NGX_LOG_DEBUG_STREAM, c->log, 0, "stream PROXY protocol handler"); if (rev->timedout) { ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out"); ngx_stream_finalize_session(s, NGX_STREAM_OK); return; } n = recv(c->fd, (char *) buf, sizeof(buf), MSG_PEEK); err = ngx_socket_errno; ngx_log_debug1(NGX_LOG_DEBUG_STREAM, c->log, 0, "recv(): %z", n); if (n == -1) { if (err == NGX_EAGAIN) { rev->ready = 0; if (!rev->timer_set) { cscf = ngx_stream_get_module_srv_conf(s, ngx_stream_core_module); ngx_add_timer(rev, cscf->proxy_protocol_timeout); } if (ngx_handle_read_event(rev, 0) != NGX_OK) { ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR); } return; } ngx_connection_error(c, err, "recv() failed"); ngx_stream_finalize_session(s, NGX_STREAM_OK); return; } if (rev->timer_set) { ngx_del_timer(rev); } p = ngx_proxy_protocol_read(c, buf, buf + n); if (p == NULL) { ngx_stream_finalize_session(s, NGX_STREAM_BAD_REQUEST); return; } size = p - buf; if (c->recv(c, buf, size) != (ssize_t) size) { ngx_stream_finalize_session(s, NGX_STREAM_INTERNAL_SERVER_ERROR); return; } c->log->action = "initializing session"; ngx_stream_session_handler(rev); } void ngx_stream_session_handler(ngx_event_t *rev) { ngx_connection_t *c; ngx_stream_session_t *s; c = rev->data; s = c->data; ngx_stream_core_run_phases(s); } void ngx_stream_finalize_session(ngx_stream_session_t *s, ngx_uint_t rc) { ngx_log_debug1(NGX_LOG_DEBUG_STREAM, s->connection->log, 0, "finalize stream session: %i", rc); s->status = rc; ngx_stream_log_session(s); ngx_stream_close_connection(s->connection); } static void ngx_stream_log_session(ngx_stream_session_t *s) { ngx_uint_t i, n; ngx_stream_handler_pt *log_handler; ngx_stream_core_main_conf_t *cmcf; cmcf = ngx_stream_get_module_main_conf(s, ngx_stream_core_module); log_handler = cmcf->phases[NGX_STREAM_LOG_PHASE].handlers.elts; n = cmcf->phases[NGX_STREAM_LOG_PHASE].handlers.nelts; for (i = 0; i < n; i++) { log_handler[i](s); } } static void ngx_stream_close_connection(ngx_connection_t *c) { ngx_pool_t *pool; ngx_log_debug1(NGX_LOG_DEBUG_STREAM, c->log, 0, "close stream connection: %d", c->fd); #if (NGX_STREAM_SSL) if (c->ssl) { if (ngx_ssl_shutdown(c) == NGX_AGAIN) { c->ssl->handler = ngx_stream_close_connection; return; } } #endif #if (NGX_STAT_STUB) (void) ngx_atomic_fetch_add(ngx_stat_active, -1); #endif pool = c->pool; ngx_close_connection(c); ngx_destroy_pool(pool); } static u_char * ngx_stream_log_error(ngx_log_t *log, u_char *buf, size_t len) { u_char *p; ngx_stream_session_t *s; if (log->action) { p = ngx_snprintf(buf, len, " while %s", log->action); len -= p - buf; buf = p; } s = log->data; p = ngx_snprintf(buf, len, ", %sclient: %V, server: %V", s->connection->type == SOCK_DGRAM ? "udp " : "", &s->connection->addr_text, &s->connection->listening->addr_text); len -= p - buf; buf = p; if (s->log_handler) { p = s->log_handler(log, buf, len); } return p; }