view src/core/ngx_core.h @ 9300:5be23505292b default tip

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 7603284f7af5
children
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_CORE_H_INCLUDED_
#define _NGX_CORE_H_INCLUDED_


#include <ngx_config.h>


typedef struct ngx_module_s          ngx_module_t;
typedef struct ngx_conf_s            ngx_conf_t;
typedef struct ngx_cycle_s           ngx_cycle_t;
typedef struct ngx_pool_s            ngx_pool_t;
typedef struct ngx_chain_s           ngx_chain_t;
typedef struct ngx_log_s             ngx_log_t;
typedef struct ngx_open_file_s       ngx_open_file_t;
typedef struct ngx_command_s         ngx_command_t;
typedef struct ngx_file_s            ngx_file_t;
typedef struct ngx_event_s           ngx_event_t;
typedef struct ngx_event_aio_s       ngx_event_aio_t;
typedef struct ngx_connection_s      ngx_connection_t;
typedef struct ngx_thread_task_s     ngx_thread_task_t;
typedef struct ngx_ssl_s             ngx_ssl_t;
typedef struct ngx_proxy_protocol_s  ngx_proxy_protocol_t;
typedef struct ngx_quic_stream_s     ngx_quic_stream_t;
typedef struct ngx_ssl_connection_s  ngx_ssl_connection_t;
typedef struct ngx_udp_connection_s  ngx_udp_connection_t;

typedef void (*ngx_event_handler_pt)(ngx_event_t *ev);
typedef void (*ngx_connection_handler_pt)(ngx_connection_t *c);


#define  NGX_OK          0
#define  NGX_ERROR      -1
#define  NGX_AGAIN      -2
#define  NGX_BUSY       -3
#define  NGX_DONE       -4
#define  NGX_DECLINED   -5
#define  NGX_ABORT      -6


#include <ngx_errno.h>
#include <ngx_atomic.h>
#include <ngx_thread.h>
#include <ngx_rbtree.h>
#include <ngx_time.h>
#include <ngx_socket.h>
#include <ngx_string.h>
#include <ngx_files.h>
#include <ngx_shmem.h>
#include <ngx_process.h>
#include <ngx_user.h>
#include <ngx_dlopen.h>
#include <ngx_parse.h>
#include <ngx_parse_time.h>
#include <ngx_log.h>
#include <ngx_alloc.h>
#include <ngx_palloc.h>
#include <ngx_buf.h>
#include <ngx_queue.h>
#include <ngx_array.h>
#include <ngx_list.h>
#include <ngx_hash.h>
#include <ngx_file.h>
#include <ngx_crc.h>
#include <ngx_crc32.h>
#include <ngx_murmurhash.h>
#if (NGX_PCRE)
#include <ngx_regex.h>
#endif
#include <ngx_radix_tree.h>
#include <ngx_times.h>
#include <ngx_rwlock.h>
#include <ngx_shmtx.h>
#include <ngx_slab.h>
#include <ngx_inet.h>
#include <ngx_cycle.h>
#include <ngx_resolver.h>
#if (NGX_OPENSSL)
#include <ngx_event_openssl.h>
#if (NGX_QUIC)
#include <ngx_event_quic.h>
#endif
#endif
#include <ngx_process_cycle.h>
#include <ngx_conf_file.h>
#include <ngx_module.h>
#include <ngx_open_file_cache.h>
#include <ngx_os.h>
#include <ngx_connection.h>
#include <ngx_syslog.h>
#include <ngx_proxy_protocol.h>
#if (NGX_HAVE_BPF)
#include <ngx_bpf.h>
#endif


#define LF     (u_char) '\n'
#define CR     (u_char) '\r'
#define CRLF   "\r\n"


#define ngx_abs(value)       (((value) >= 0) ? (value) : - (value))
#define ngx_max(val1, val2)  ((val1 < val2) ? (val2) : (val1))
#define ngx_min(val1, val2)  ((val1 > val2) ? (val2) : (val1))

void ngx_cpuinfo(void);

#if (NGX_HAVE_OPENAT)
#define NGX_DISABLE_SYMLINKS_OFF        0
#define NGX_DISABLE_SYMLINKS_ON         1
#define NGX_DISABLE_SYMLINKS_NOTOWNER   2
#endif

#endif /* _NGX_CORE_H_INCLUDED_ */