Mercurial > hg > nginx
view src/event/ngx_event_timer.c @ 7440:6d4bc025c5a7
Prevented scheduling events on a shared connection.
A shared connection does not own its file descriptor, which means that
ngx_handle_read_event/ngx_handle_write_event calls should do nothing for it.
Currently the c->shared flag is checked in several places in the stream proxy
module prior to calling these functions. However it was not done everywhere.
Missing checks could lead to calling
ngx_handle_read_event/ngx_handle_write_event on shared connections.
The problem manifested itself when using proxy_upload_rate and resulted in
either duplicate file descriptor error (e.g. with epoll) or incorrect further
udp packet processing (e.g. with kqueue).
The fix is to set and reset the event active flag in a way that prevents
ngx_handle_read_event/ngx_handle_write_event from scheduling socket events.
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Mon, 14 Jan 2019 20:36:23 +0300 |
parents | 03928f7f209b |
children | 0c5e84096d99 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> ngx_rbtree_t ngx_event_timer_rbtree; static ngx_rbtree_node_t ngx_event_timer_sentinel; /* * the event timer rbtree may contain the duplicate keys, however, * it should not be a problem, because we use the rbtree to find * a minimum timer value only */ ngx_int_t ngx_event_timer_init(ngx_log_t *log) { ngx_rbtree_init(&ngx_event_timer_rbtree, &ngx_event_timer_sentinel, ngx_rbtree_insert_timer_value); return NGX_OK; } ngx_msec_t ngx_event_find_timer(void) { ngx_msec_int_t timer; ngx_rbtree_node_t *node, *root, *sentinel; if (ngx_event_timer_rbtree.root == &ngx_event_timer_sentinel) { return NGX_TIMER_INFINITE; } root = ngx_event_timer_rbtree.root; sentinel = ngx_event_timer_rbtree.sentinel; node = ngx_rbtree_min(root, sentinel); timer = (ngx_msec_int_t) (node->key - ngx_current_msec); return (ngx_msec_t) (timer > 0 ? timer : 0); } void ngx_event_expire_timers(void) { ngx_event_t *ev; ngx_rbtree_node_t *node, *root, *sentinel; sentinel = ngx_event_timer_rbtree.sentinel; for ( ;; ) { root = ngx_event_timer_rbtree.root; if (root == sentinel) { return; } node = ngx_rbtree_min(root, sentinel); /* node->key > ngx_current_msec */ if ((ngx_msec_int_t) (node->key - ngx_current_msec) > 0) { return; } ev = (ngx_event_t *) ((char *) node - offsetof(ngx_event_t, timer)); ngx_log_debug2(NGX_LOG_DEBUG_EVENT, ev->log, 0, "event timer del: %d: %M", ngx_event_ident(ev->data), ev->timer.key); ngx_rbtree_delete(&ngx_event_timer_rbtree, &ev->timer); #if (NGX_DEBUG) ev->timer.left = NULL; ev->timer.right = NULL; ev->timer.parent = NULL; #endif ev->timer_set = 0; ev->timedout = 1; ev->handler(ev); } } ngx_int_t ngx_event_no_timers_left(void) { ngx_event_t *ev; ngx_rbtree_node_t *node, *root, *sentinel; sentinel = ngx_event_timer_rbtree.sentinel; root = ngx_event_timer_rbtree.root; if (root == sentinel) { return NGX_OK; } for (node = ngx_rbtree_min(root, sentinel); node; node = ngx_rbtree_next(&ngx_event_timer_rbtree, node)) { ev = (ngx_event_t *) ((char *) node - offsetof(ngx_event_t, timer)); if (!ev->cancelable) { return NGX_AGAIN; } } /* only cancelable timers left */ return NGX_OK; }