Mercurial > hg > nginx
view src/http/v2/ngx_http_v2.h @ 9203:0de20f43db25
Fixed request termination with AIO and subrequests (ticket #2555).
When a request was terminated due to an error via ngx_http_terminate_request()
while an AIO operation was running in a subrequest, various issues were
observed. This happened because ngx_http_request_finalizer() was only set
in the subrequest where ngx_http_terminate_request() was called, but not
in the subrequest where the AIO operation was running. After completion
of the AIO operation normal processing of the subrequest was resumed, leading
to issues.
In particular, in case of the upstream module, termination of the request
called upstream cleanup, which closed the upstream connection. Attempts to
further work with the upstream connection after AIO operation completion
resulted in segfaults in ngx_ssl_recv(), "readv() failed (9: Bad file
descriptor) while reading upstream" errors, or socket leaks.
In ticket #2555, issues were observed with the following configuration
with cache background update (with thread writing instrumented to
introduce a delay, when a client closes the connection during an update):
location = /background-and-aio-write {
proxy_pass ...
proxy_cache one;
proxy_cache_valid 200 1s;
proxy_cache_background_update on;
proxy_cache_use_stale updating;
aio threads;
aio_write on;
limit_rate 1000;
}
Similarly, the same issue can be seen with SSI, and can be caused by
errors in subrequests, such as in the following configuration
(where "/proxy" uses AIO, and "/sleep" returns 444 after some delay,
causing request termination):
location = /ssi-active-boom {
ssi on;
ssi_types *;
return 200 '
<!--#include virtual="/proxy" -->
<!--#include virtual="/sleep" -->
';
limit_rate 1000;
}
Or the same with both AIO operation and the error in non-active subrequests
(which needs slightly different handling, see below):
location = /ssi-non-active-boom {
ssi on;
ssi_types *;
return 200 '
<!--#include virtual="/static" -->
<!--#include virtual="/proxy" -->
<!--#include virtual="/sleep" -->
';
limit_rate 1000;
}
Similarly, issues can be observed with just static files. However,
with static files potential impact is limited due to timeout safeguards
in ngx_http_writer(), and the fact that c->error is set during request
termination.
In a simple configuration with an AIO operation in the active subrequest,
such as in the following configuration, the connection is closed right
after completion of the AIO operation anyway, since ngx_http_writer()
tries to write to the connection and fails due to c->error set:
location = /ssi-active-static-boom {
ssi on;
ssi_types *;
return 200 '
<!--#include virtual="/static-aio" -->
<!--#include virtual="/sleep" -->
';
limit_rate 1000;
}
In the following configuration, with an AIO operation in a non-active
subrequest, the connection is closed only after send_timeout expires:
location = /ssi-non-active-static-boom {
ssi on;
ssi_types *;
return 200 '
<!--#include virtual="/static" -->
<!--#include virtual="/static-aio" -->
<!--#include virtual="/sleep" -->
';
limit_rate 1000;
}
Fix is to introduce r->main->terminated flag, which is to be checked
by AIO event handlers when the r->main->blocked counter is decremented.
When the flag is set, handlers are expected to wake up the connection
instead of the subrequest (which might be already cleaned up).
Additionally, now ngx_http_request_finalizer() is always set in the
active subrequest, so waking up the connection properly finalizes the
request even if termination happened in a non-active subrequest.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Tue, 30 Jan 2024 03:20:05 +0300 |
parents | cdda286c0f1b |
children |
line wrap: on
line source
/* * Copyright (C) Nginx, Inc. * Copyright (C) Valentin V. Bartenev */ #ifndef _NGX_HTTP_V2_H_INCLUDED_ #define _NGX_HTTP_V2_H_INCLUDED_ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> #define NGX_HTTP_V2_ALPN_PROTO "\x02h2" #define NGX_HTTP_V2_STATE_BUFFER_SIZE 16 #define NGX_HTTP_V2_DEFAULT_FRAME_SIZE (1 << 14) #define NGX_HTTP_V2_MAX_FRAME_SIZE ((1 << 24) - 1) #define NGX_HTTP_V2_INT_OCTETS 4 #define NGX_HTTP_V2_MAX_FIELD \ (127 + (1 << (NGX_HTTP_V2_INT_OCTETS - 1) * 7) - 1) #define NGX_HTTP_V2_FRAME_HEADER_SIZE 9 /* frame types */ #define NGX_HTTP_V2_DATA_FRAME 0x0 #define NGX_HTTP_V2_HEADERS_FRAME 0x1 #define NGX_HTTP_V2_PRIORITY_FRAME 0x2 #define NGX_HTTP_V2_RST_STREAM_FRAME 0x3 #define NGX_HTTP_V2_SETTINGS_FRAME 0x4 #define NGX_HTTP_V2_PUSH_PROMISE_FRAME 0x5 #define NGX_HTTP_V2_PING_FRAME 0x6 #define NGX_HTTP_V2_GOAWAY_FRAME 0x7 #define NGX_HTTP_V2_WINDOW_UPDATE_FRAME 0x8 #define NGX_HTTP_V2_CONTINUATION_FRAME 0x9 /* frame flags */ #define NGX_HTTP_V2_NO_FLAG 0x00 #define NGX_HTTP_V2_ACK_FLAG 0x01 #define NGX_HTTP_V2_END_STREAM_FLAG 0x01 #define NGX_HTTP_V2_END_HEADERS_FLAG 0x04 #define NGX_HTTP_V2_PADDED_FLAG 0x08 #define NGX_HTTP_V2_PRIORITY_FLAG 0x20 #define NGX_HTTP_V2_MAX_WINDOW ((1U << 31) - 1) #define NGX_HTTP_V2_DEFAULT_WINDOW 65535 #define NGX_HTTP_V2_DEFAULT_WEIGHT 16 typedef struct ngx_http_v2_connection_s ngx_http_v2_connection_t; typedef struct ngx_http_v2_node_s ngx_http_v2_node_t; typedef struct ngx_http_v2_out_frame_s ngx_http_v2_out_frame_t; typedef u_char *(*ngx_http_v2_handler_pt) (ngx_http_v2_connection_t *h2c, u_char *pos, u_char *end); typedef struct { ngx_flag_t enable; size_t pool_size; ngx_uint_t concurrent_streams; size_t preread_size; ngx_uint_t streams_index_mask; } ngx_http_v2_srv_conf_t; typedef struct { ngx_str_t name; ngx_str_t value; } ngx_http_v2_header_t; typedef struct { ngx_uint_t sid; size_t length; size_t padding; unsigned flags:8; unsigned incomplete:1; unsigned keep_pool:1; /* HPACK */ unsigned parse_name:1; unsigned parse_value:1; unsigned index:1; ngx_http_v2_header_t header; size_t header_limit; u_char field_state; u_char *field_start; u_char *field_end; size_t field_rest; ngx_pool_t *pool; ngx_http_v2_stream_t *stream; u_char buffer[NGX_HTTP_V2_STATE_BUFFER_SIZE]; size_t buffer_used; ngx_http_v2_handler_pt handler; } ngx_http_v2_state_t; typedef struct { ngx_http_v2_header_t **entries; ngx_uint_t added; ngx_uint_t deleted; ngx_uint_t reused; ngx_uint_t allocated; size_t size; size_t free; u_char *storage; u_char *pos; } ngx_http_v2_hpack_t; struct ngx_http_v2_connection_s { ngx_connection_t *connection; ngx_http_connection_t *http_connection; off_t total_bytes; off_t payload_bytes; ngx_uint_t processing; ngx_uint_t frames; ngx_uint_t idle; ngx_uint_t new_streams; ngx_uint_t refused_streams; ngx_uint_t priority_limit; size_t send_window; size_t recv_window; size_t init_window; size_t frame_size; ngx_queue_t waiting; ngx_http_v2_state_t state; ngx_http_v2_hpack_t hpack; ngx_pool_t *pool; ngx_http_v2_out_frame_t *free_frames; ngx_connection_t *free_fake_connections; ngx_http_v2_node_t **streams_index; ngx_http_v2_out_frame_t *last_out; ngx_queue_t dependencies; ngx_queue_t closed; ngx_uint_t closed_nodes; ngx_uint_t last_sid; time_t lingering_time; unsigned settings_ack:1; unsigned table_update:1; unsigned blocked:1; unsigned goaway:1; }; struct ngx_http_v2_node_s { ngx_uint_t id; ngx_http_v2_node_t *index; ngx_http_v2_node_t *parent; ngx_queue_t queue; ngx_queue_t children; ngx_queue_t reuse; ngx_uint_t rank; ngx_uint_t weight; double rel_weight; ngx_http_v2_stream_t *stream; }; struct ngx_http_v2_stream_s { ngx_http_request_t *request; ngx_http_v2_connection_t *connection; ngx_http_v2_node_t *node; ngx_uint_t queued; /* * A change to SETTINGS_INITIAL_WINDOW_SIZE could cause the * send_window to become negative, hence it's signed. */ ssize_t send_window; size_t recv_window; ngx_buf_t *preread; ngx_uint_t frames; ngx_http_v2_out_frame_t *free_frames; ngx_chain_t *free_frame_headers; ngx_chain_t *free_bufs; ngx_queue_t queue; ngx_array_t *cookies; ngx_pool_t *pool; unsigned waiting:1; unsigned blocked:1; unsigned exhausted:1; unsigned in_closed:1; unsigned out_closed:1; unsigned rst_sent:1; unsigned no_flow_control:1; unsigned skip_data:1; }; struct ngx_http_v2_out_frame_s { ngx_http_v2_out_frame_t *next; ngx_chain_t *first; ngx_chain_t *last; ngx_int_t (*handler)(ngx_http_v2_connection_t *h2c, ngx_http_v2_out_frame_t *frame); ngx_http_v2_stream_t *stream; size_t length; unsigned blocked:1; unsigned fin:1; }; static ngx_inline void ngx_http_v2_queue_frame(ngx_http_v2_connection_t *h2c, ngx_http_v2_out_frame_t *frame) { ngx_http_v2_out_frame_t **out; for (out = &h2c->last_out; *out; out = &(*out)->next) { if ((*out)->blocked || (*out)->stream == NULL) { break; } if ((*out)->stream->node->rank < frame->stream->node->rank || ((*out)->stream->node->rank == frame->stream->node->rank && (*out)->stream->node->rel_weight >= frame->stream->node->rel_weight)) { break; } } frame->next = *out; *out = frame; } static ngx_inline void ngx_http_v2_queue_blocked_frame(ngx_http_v2_connection_t *h2c, ngx_http_v2_out_frame_t *frame) { ngx_http_v2_out_frame_t **out; for (out = &h2c->last_out; *out; out = &(*out)->next) { if ((*out)->blocked || (*out)->stream == NULL) { break; } } frame->next = *out; *out = frame; } static ngx_inline void ngx_http_v2_queue_ordered_frame(ngx_http_v2_connection_t *h2c, ngx_http_v2_out_frame_t *frame) { frame->next = h2c->last_out; h2c->last_out = frame; } void ngx_http_v2_init(ngx_event_t *rev); ngx_int_t ngx_http_v2_read_request_body(ngx_http_request_t *r); ngx_int_t ngx_http_v2_read_unbuffered_request_body(ngx_http_request_t *r); void ngx_http_v2_close_stream(ngx_http_v2_stream_t *stream, ngx_int_t rc); ngx_int_t ngx_http_v2_send_output_queue(ngx_http_v2_connection_t *h2c); ngx_str_t *ngx_http_v2_get_static_name(ngx_uint_t index); ngx_str_t *ngx_http_v2_get_static_value(ngx_uint_t index); ngx_int_t ngx_http_v2_get_indexed_header(ngx_http_v2_connection_t *h2c, ngx_uint_t index, ngx_uint_t name_only); ngx_int_t ngx_http_v2_add_header(ngx_http_v2_connection_t *h2c, ngx_http_v2_header_t *header); ngx_int_t ngx_http_v2_table_size(ngx_http_v2_connection_t *h2c, size_t size); #define ngx_http_v2_prefix(bits) ((1 << (bits)) - 1) #if (NGX_HAVE_NONALIGNED) #define ngx_http_v2_parse_uint16(p) ntohs(*(uint16_t *) (p)) #define ngx_http_v2_parse_uint32(p) ntohl(*(uint32_t *) (p)) #else #define ngx_http_v2_parse_uint16(p) ((p)[0] << 8 | (p)[1]) #define ngx_http_v2_parse_uint32(p) \ ((uint32_t) (p)[0] << 24 | (p)[1] << 16 | (p)[2] << 8 | (p)[3]) #endif #define ngx_http_v2_parse_length(p) ((p) >> 8) #define ngx_http_v2_parse_type(p) ((p) & 0xff) #define ngx_http_v2_parse_sid(p) (ngx_http_v2_parse_uint32(p) & 0x7fffffff) #define ngx_http_v2_parse_window(p) (ngx_http_v2_parse_uint32(p) & 0x7fffffff) #define ngx_http_v2_write_uint16_aligned(p, s) \ (*(uint16_t *) (p) = htons((uint16_t) (s)), (p) + sizeof(uint16_t)) #define ngx_http_v2_write_uint32_aligned(p, s) \ (*(uint32_t *) (p) = htonl((uint32_t) (s)), (p) + sizeof(uint32_t)) #if (NGX_HAVE_NONALIGNED) #define ngx_http_v2_write_uint16 ngx_http_v2_write_uint16_aligned #define ngx_http_v2_write_uint32 ngx_http_v2_write_uint32_aligned #else #define ngx_http_v2_write_uint16(p, s) \ ((p)[0] = (u_char) ((s) >> 8), \ (p)[1] = (u_char) (s), \ (p) + sizeof(uint16_t)) #define ngx_http_v2_write_uint32(p, s) \ ((p)[0] = (u_char) ((s) >> 24), \ (p)[1] = (u_char) ((s) >> 16), \ (p)[2] = (u_char) ((s) >> 8), \ (p)[3] = (u_char) (s), \ (p) + sizeof(uint32_t)) #endif #define ngx_http_v2_write_len_and_type(p, l, t) \ ngx_http_v2_write_uint32_aligned(p, (l) << 8 | (t)) #define ngx_http_v2_write_sid ngx_http_v2_write_uint32 #define ngx_http_v2_indexed(i) (128 + (i)) #define ngx_http_v2_inc_indexed(i) (64 + (i)) #define ngx_http_v2_write_name(dst, src, len, tmp) \ ngx_http_v2_string_encode(dst, src, len, tmp, 1) #define ngx_http_v2_write_value(dst, src, len, tmp) \ ngx_http_v2_string_encode(dst, src, len, tmp, 0) #define NGX_HTTP_V2_ENCODE_RAW 0 #define NGX_HTTP_V2_ENCODE_HUFF 0x80 #define NGX_HTTP_V2_AUTHORITY_INDEX 1 #define NGX_HTTP_V2_METHOD_INDEX 2 #define NGX_HTTP_V2_METHOD_GET_INDEX 2 #define NGX_HTTP_V2_METHOD_POST_INDEX 3 #define NGX_HTTP_V2_PATH_INDEX 4 #define NGX_HTTP_V2_PATH_ROOT_INDEX 4 #define NGX_HTTP_V2_SCHEME_HTTP_INDEX 6 #define NGX_HTTP_V2_SCHEME_HTTPS_INDEX 7 #define NGX_HTTP_V2_STATUS_INDEX 8 #define NGX_HTTP_V2_STATUS_200_INDEX 8 #define NGX_HTTP_V2_STATUS_204_INDEX 9 #define NGX_HTTP_V2_STATUS_206_INDEX 10 #define NGX_HTTP_V2_STATUS_304_INDEX 11 #define NGX_HTTP_V2_STATUS_400_INDEX 12 #define NGX_HTTP_V2_STATUS_404_INDEX 13 #define NGX_HTTP_V2_STATUS_500_INDEX 14 #define NGX_HTTP_V2_CONTENT_LENGTH_INDEX 28 #define NGX_HTTP_V2_CONTENT_TYPE_INDEX 31 #define NGX_HTTP_V2_DATE_INDEX 33 #define NGX_HTTP_V2_LAST_MODIFIED_INDEX 44 #define NGX_HTTP_V2_LOCATION_INDEX 46 #define NGX_HTTP_V2_SERVER_INDEX 54 #define NGX_HTTP_V2_VARY_INDEX 59 #define NGX_HTTP_V2_PREFACE_START "PRI * HTTP/2.0\r\n" #define NGX_HTTP_V2_PREFACE_END "\r\nSM\r\n\r\n" #define NGX_HTTP_V2_PREFACE NGX_HTTP_V2_PREFACE_START \ NGX_HTTP_V2_PREFACE_END u_char *ngx_http_v2_string_encode(u_char *dst, u_char *src, size_t len, u_char *tmp, ngx_uint_t lower); extern ngx_module_t ngx_http_v2_module; #endif /* _NGX_HTTP_V2_H_INCLUDED_ */