Mercurial > hg > nginx
view src/core/ngx_hash.h @ 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 | f8f6b9fee66a |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #ifndef _NGX_HASH_H_INCLUDED_ #define _NGX_HASH_H_INCLUDED_ #include <ngx_config.h> #include <ngx_core.h> typedef struct { void *value; u_short len; u_char name[1]; } ngx_hash_elt_t; typedef struct { ngx_hash_elt_t **buckets; ngx_uint_t size; } ngx_hash_t; typedef struct { ngx_hash_t hash; void *value; } ngx_hash_wildcard_t; typedef struct { ngx_str_t key; ngx_uint_t key_hash; void *value; } ngx_hash_key_t; typedef ngx_uint_t (*ngx_hash_key_pt) (u_char *data, size_t len); typedef struct { ngx_hash_t hash; ngx_hash_wildcard_t *wc_head; ngx_hash_wildcard_t *wc_tail; } ngx_hash_combined_t; typedef struct { ngx_hash_t *hash; ngx_hash_key_pt key; ngx_uint_t max_size; ngx_uint_t bucket_size; char *name; ngx_pool_t *pool; ngx_pool_t *temp_pool; } ngx_hash_init_t; #define NGX_HASH_SMALL 1 #define NGX_HASH_LARGE 2 #define NGX_HASH_LARGE_ASIZE 16384 #define NGX_HASH_LARGE_HSIZE 10007 #define NGX_HASH_WILDCARD_KEY 1 #define NGX_HASH_READONLY_KEY 2 typedef struct { ngx_uint_t hsize; ngx_pool_t *pool; ngx_pool_t *temp_pool; ngx_array_t keys; ngx_array_t *keys_hash; ngx_array_t dns_wc_head; ngx_array_t *dns_wc_head_hash; ngx_array_t dns_wc_tail; ngx_array_t *dns_wc_tail_hash; } ngx_hash_keys_arrays_t; typedef struct ngx_table_elt_s ngx_table_elt_t; struct ngx_table_elt_s { ngx_uint_t hash; ngx_str_t key; ngx_str_t value; u_char *lowcase_key; ngx_table_elt_t *next; }; void *ngx_hash_find(ngx_hash_t *hash, ngx_uint_t key, u_char *name, size_t len); void *ngx_hash_find_wc_head(ngx_hash_wildcard_t *hwc, u_char *name, size_t len); void *ngx_hash_find_wc_tail(ngx_hash_wildcard_t *hwc, u_char *name, size_t len); void *ngx_hash_find_combined(ngx_hash_combined_t *hash, ngx_uint_t key, u_char *name, size_t len); ngx_int_t ngx_hash_init(ngx_hash_init_t *hinit, ngx_hash_key_t *names, ngx_uint_t nelts); ngx_int_t ngx_hash_wildcard_init(ngx_hash_init_t *hinit, ngx_hash_key_t *names, ngx_uint_t nelts); #define ngx_hash(key, c) ((ngx_uint_t) key * 31 + c) ngx_uint_t ngx_hash_key(u_char *data, size_t len); ngx_uint_t ngx_hash_key_lc(u_char *data, size_t len); ngx_uint_t ngx_hash_strlow(u_char *dst, u_char *src, size_t n); ngx_int_t ngx_hash_keys_array_init(ngx_hash_keys_arrays_t *ha, ngx_uint_t type); ngx_int_t ngx_hash_add_key(ngx_hash_keys_arrays_t *ha, ngx_str_t *key, void *value, ngx_uint_t flags); #endif /* _NGX_HASH_H_INCLUDED_ */