Mercurial > hg > nginx-quic
view src/event/modules/ngx_devpoll_module.c @ 8895:457afc332c67
Stream: don't flush empty buffers created for read errors.
When we generate the last_buf buffer for an UDP upstream recv error, it does
not contain any data from the wire. ngx_stream_write_filter attempts to forward
it anyways, which is incorrect (e.g., UDP upstream ECONNREFUSED will be
translated to an empty packet).
This happens because we mark the buffer as both 'flush' and 'last_buf', and
ngx_stream_write_filter has special handling for flush with certain types of
connections (see d127837c714f, 32b0ba4855a6). The flags are meant to be
mutually exclusive, so the fix is to ensure that flush and last_buf are not set
at the same time.
Reproduction:
stream {
upstream unreachable {
server 127.0.0.1:8880;
}
server {
listen 127.0.0.1:8998 udp;
proxy_pass unreachable;
}
}
1 0.000000000 127.0.0.1 → 127.0.0.1 UDP 47 45588 → 8998 Len=5
2 0.000166300 127.0.0.1 → 127.0.0.1 UDP 47 51149 → 8880 Len=5
3 0.000172600 127.0.0.1 → 127.0.0.1 ICMP 75 Destination unreachable (Port
unreachable)
4 0.000202400 127.0.0.1 → 127.0.0.1 UDP 42 8998 → 45588 Len=0
Fixes d127837c714f.
author | Aleksei Bavshin <a.bavshin@f5.com> |
---|---|
date | Mon, 23 May 2022 11:29:44 -0700 |
parents | efd71d49bde0 |
children |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #if (NGX_TEST_BUILD_DEVPOLL) /* Solaris declarations */ #ifndef POLLREMOVE #define POLLREMOVE 0x0800 #endif #define DP_POLL 0xD001 #define DP_ISPOLLED 0xD002 struct dvpoll { struct pollfd *dp_fds; int dp_nfds; int dp_timeout; }; #endif typedef struct { ngx_uint_t changes; ngx_uint_t events; } ngx_devpoll_conf_t; static ngx_int_t ngx_devpoll_init(ngx_cycle_t *cycle, ngx_msec_t timer); static void ngx_devpoll_done(ngx_cycle_t *cycle); static ngx_int_t ngx_devpoll_add_event(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags); static ngx_int_t ngx_devpoll_del_event(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags); static ngx_int_t ngx_devpoll_set_event(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags); static ngx_int_t ngx_devpoll_process_events(ngx_cycle_t *cycle, ngx_msec_t timer, ngx_uint_t flags); static void *ngx_devpoll_create_conf(ngx_cycle_t *cycle); static char *ngx_devpoll_init_conf(ngx_cycle_t *cycle, void *conf); static int dp = -1; static struct pollfd *change_list, *event_list; static ngx_uint_t nchanges, max_changes, nevents; static ngx_event_t **change_index; static ngx_str_t devpoll_name = ngx_string("/dev/poll"); static ngx_command_t ngx_devpoll_commands[] = { { ngx_string("devpoll_changes"), NGX_EVENT_CONF|NGX_CONF_TAKE1, ngx_conf_set_num_slot, 0, offsetof(ngx_devpoll_conf_t, changes), NULL }, { ngx_string("devpoll_events"), NGX_EVENT_CONF|NGX_CONF_TAKE1, ngx_conf_set_num_slot, 0, offsetof(ngx_devpoll_conf_t, events), NULL }, ngx_null_command }; static ngx_event_module_t ngx_devpoll_module_ctx = { &devpoll_name, ngx_devpoll_create_conf, /* create configuration */ ngx_devpoll_init_conf, /* init configuration */ { ngx_devpoll_add_event, /* add an event */ ngx_devpoll_del_event, /* delete an event */ ngx_devpoll_add_event, /* enable an event */ ngx_devpoll_del_event, /* disable an event */ NULL, /* add an connection */ NULL, /* delete an connection */ NULL, /* trigger a notify */ ngx_devpoll_process_events, /* process the events */ ngx_devpoll_init, /* init the events */ ngx_devpoll_done, /* done the events */ } }; ngx_module_t ngx_devpoll_module = { NGX_MODULE_V1, &ngx_devpoll_module_ctx, /* module context */ ngx_devpoll_commands, /* module directives */ NGX_EVENT_MODULE, /* module type */ NULL, /* init master */ NULL, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static ngx_int_t ngx_devpoll_init(ngx_cycle_t *cycle, ngx_msec_t timer) { size_t n; ngx_devpoll_conf_t *dpcf; dpcf = ngx_event_get_conf(cycle->conf_ctx, ngx_devpoll_module); if (dp == -1) { dp = open("/dev/poll", O_RDWR); if (dp == -1) { ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno, "open(/dev/poll) failed"); return NGX_ERROR; } } if (max_changes < dpcf->changes) { if (nchanges) { n = nchanges * sizeof(struct pollfd); if (write(dp, change_list, n) != (ssize_t) n) { ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, "write(/dev/poll) failed"); return NGX_ERROR; } nchanges = 0; } if (change_list) { ngx_free(change_list); } change_list = ngx_alloc(sizeof(struct pollfd) * dpcf->changes, cycle->log); if (change_list == NULL) { return NGX_ERROR; } if (change_index) { ngx_free(change_index); } change_index = ngx_alloc(sizeof(ngx_event_t *) * dpcf->changes, cycle->log); if (change_index == NULL) { return NGX_ERROR; } } max_changes = dpcf->changes; if (nevents < dpcf->events) { if (event_list) { ngx_free(event_list); } event_list = ngx_alloc(sizeof(struct pollfd) * dpcf->events, cycle->log); if (event_list == NULL) { return NGX_ERROR; } } nevents = dpcf->events; ngx_io = ngx_os_io; ngx_event_actions = ngx_devpoll_module_ctx.actions; ngx_event_flags = NGX_USE_LEVEL_EVENT|NGX_USE_FD_EVENT; return NGX_OK; } static void ngx_devpoll_done(ngx_cycle_t *cycle) { if (close(dp) == -1) { ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, "close(/dev/poll) failed"); } dp = -1; ngx_free(change_list); ngx_free(event_list); ngx_free(change_index); change_list = NULL; event_list = NULL; change_index = NULL; max_changes = 0; nchanges = 0; nevents = 0; } static ngx_int_t ngx_devpoll_add_event(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags) { #if (NGX_DEBUG) ngx_connection_t *c; #endif #if (NGX_READ_EVENT != POLLIN) event = (event == NGX_READ_EVENT) ? POLLIN : POLLOUT; #endif #if (NGX_DEBUG) c = ev->data; ngx_log_debug2(NGX_LOG_DEBUG_EVENT, ev->log, 0, "devpoll add event: fd:%d ev:%04Xi", c->fd, event); #endif ev->active = 1; return ngx_devpoll_set_event(ev, event, 0); } static ngx_int_t ngx_devpoll_del_event(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags) { ngx_event_t *e; ngx_connection_t *c; c = ev->data; #if (NGX_READ_EVENT != POLLIN) event = (event == NGX_READ_EVENT) ? POLLIN : POLLOUT; #endif ngx_log_debug2(NGX_LOG_DEBUG_EVENT, ev->log, 0, "devpoll del event: fd:%d ev:%04Xi", c->fd, event); if (ngx_devpoll_set_event(ev, POLLREMOVE, flags) == NGX_ERROR) { return NGX_ERROR; } ev->active = 0; if (flags & NGX_CLOSE_EVENT) { e = (event == POLLIN) ? c->write : c->read; if (e) { e->active = 0; } return NGX_OK; } /* restore the pair event if it exists */ if (event == POLLIN) { e = c->write; event = POLLOUT; } else { e = c->read; event = POLLIN; } if (e && e->active) { return ngx_devpoll_set_event(e, event, 0); } return NGX_OK; } static ngx_int_t ngx_devpoll_set_event(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags) { size_t n; ngx_connection_t *c; c = ev->data; ngx_log_debug3(NGX_LOG_DEBUG_EVENT, ev->log, 0, "devpoll fd:%d ev:%04Xi fl:%04Xi", c->fd, event, flags); if (nchanges >= max_changes) { ngx_log_error(NGX_LOG_WARN, ev->log, 0, "/dev/pool change list is filled up"); n = nchanges * sizeof(struct pollfd); if (write(dp, change_list, n) != (ssize_t) n) { ngx_log_error(NGX_LOG_ALERT, ev->log, ngx_errno, "write(/dev/poll) failed"); return NGX_ERROR; } nchanges = 0; } change_list[nchanges].fd = c->fd; change_list[nchanges].events = (short) event; change_list[nchanges].revents = 0; change_index[nchanges] = ev; ev->index = nchanges; nchanges++; if (flags & NGX_CLOSE_EVENT) { n = nchanges * sizeof(struct pollfd); if (write(dp, change_list, n) != (ssize_t) n) { ngx_log_error(NGX_LOG_ALERT, ev->log, ngx_errno, "write(/dev/poll) failed"); return NGX_ERROR; } nchanges = 0; } return NGX_OK; } static ngx_int_t ngx_devpoll_process_events(ngx_cycle_t *cycle, ngx_msec_t timer, ngx_uint_t flags) { int events, revents, rc; size_t n; ngx_fd_t fd; ngx_err_t err; ngx_int_t i; ngx_uint_t level, instance; ngx_event_t *rev, *wev; ngx_queue_t *queue; ngx_connection_t *c; struct pollfd pfd; struct dvpoll dvp; /* NGX_TIMER_INFINITE == INFTIM */ ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "devpoll timer: %M", timer); if (nchanges) { n = nchanges * sizeof(struct pollfd); if (write(dp, change_list, n) != (ssize_t) n) { ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, "write(/dev/poll) failed"); return NGX_ERROR; } nchanges = 0; } dvp.dp_fds = event_list; dvp.dp_nfds = (int) nevents; dvp.dp_timeout = timer; events = ioctl(dp, DP_POLL, &dvp); err = (events == -1) ? ngx_errno : 0; if (flags & NGX_UPDATE_TIME || ngx_event_timer_alarm) { ngx_time_update(); } if (err) { if (err == NGX_EINTR) { if (ngx_event_timer_alarm) { ngx_event_timer_alarm = 0; return NGX_OK; } level = NGX_LOG_INFO; } else { level = NGX_LOG_ALERT; } ngx_log_error(level, cycle->log, err, "ioctl(DP_POLL) failed"); return NGX_ERROR; } if (events == 0) { if (timer != NGX_TIMER_INFINITE) { return NGX_OK; } ngx_log_error(NGX_LOG_ALERT, cycle->log, 0, "ioctl(DP_POLL) returned no events without timeout"); return NGX_ERROR; } for (i = 0; i < events; i++) { fd = event_list[i].fd; revents = event_list[i].revents; c = ngx_cycle->files[fd]; if (c == NULL || c->fd == -1) { pfd.fd = fd; pfd.events = 0; pfd.revents = 0; rc = ioctl(dp, DP_ISPOLLED, &pfd); switch (rc) { case -1: ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, "ioctl(DP_ISPOLLED) failed for socket %d, event %04Xd", fd, revents); break; case 0: ngx_log_error(NGX_LOG_ALERT, cycle->log, 0, "phantom event %04Xd for closed and removed socket %d", revents, fd); break; default: ngx_log_error(NGX_LOG_ALERT, cycle->log, 0, "unexpected event %04Xd for closed and removed socket %d, " "ioctl(DP_ISPOLLED) returned rc:%d, fd:%d, event %04Xd", revents, fd, rc, pfd.fd, pfd.revents); pfd.fd = fd; pfd.events = POLLREMOVE; pfd.revents = 0; if (write(dp, &pfd, sizeof(struct pollfd)) != (ssize_t) sizeof(struct pollfd)) { ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, "write(/dev/poll) for %d failed", fd); } if (close(fd) == -1) { ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno, "close(%d) failed", fd); } break; } continue; } ngx_log_debug3(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "devpoll: fd:%d, ev:%04Xd, rev:%04Xd", fd, event_list[i].events, revents); if (revents & (POLLERR|POLLHUP|POLLNVAL)) { ngx_log_debug3(NGX_LOG_DEBUG_EVENT, cycle->log, 0, "ioctl(DP_POLL) error fd:%d ev:%04Xd rev:%04Xd", fd, event_list[i].events, revents); } if (revents & ~(POLLIN|POLLOUT|POLLERR|POLLHUP|POLLNVAL)) { ngx_log_error(NGX_LOG_ALERT, cycle->log, 0, "strange ioctl(DP_POLL) events " "fd:%d ev:%04Xd rev:%04Xd", fd, event_list[i].events, revents); } if (revents & (POLLERR|POLLHUP|POLLNVAL)) { /* * if the error events were returned, add POLLIN and POLLOUT * to handle the events at least in one active handler */ revents |= POLLIN|POLLOUT; } rev = c->read; if ((revents & POLLIN) && rev->active) { rev->ready = 1; rev->available = -1; if (flags & NGX_POST_EVENTS) { queue = rev->accept ? &ngx_posted_accept_events : &ngx_posted_events; ngx_post_event(rev, queue); } else { instance = rev->instance; rev->handler(rev); if (c->fd == -1 || rev->instance != instance) { continue; } } } wev = c->write; if ((revents & POLLOUT) && wev->active) { wev->ready = 1; if (flags & NGX_POST_EVENTS) { ngx_post_event(wev, &ngx_posted_events); } else { wev->handler(wev); } } } return NGX_OK; } static void * ngx_devpoll_create_conf(ngx_cycle_t *cycle) { ngx_devpoll_conf_t *dpcf; dpcf = ngx_palloc(cycle->pool, sizeof(ngx_devpoll_conf_t)); if (dpcf == NULL) { return NULL; } dpcf->changes = NGX_CONF_UNSET; dpcf->events = NGX_CONF_UNSET; return dpcf; } static char * ngx_devpoll_init_conf(ngx_cycle_t *cycle, void *conf) { ngx_devpoll_conf_t *dpcf = conf; ngx_conf_init_uint_value(dpcf->changes, 32); ngx_conf_init_uint_value(dpcf->events, 32); return NGX_CONF_OK; }