Mercurial > hg > nginx
view src/core/ngx_syslog.c @ 6957:83bae3d354ab
HTTP/2: fixed connection finalization.
All streams in connection must be finalized before the connection
itself can be finalized and all related memory is freed. That's
not always possible on the current event loop iteration.
Thus when the last stream is finalized, it sets the special read
event handler ngx_http_v2_handle_connection_handler() and posts
the event.
Previously, this handler didn't check the connection state and
could call the regular event handler on a connection that was
already in finalization stage. In the worst case that could
lead to a segmentation fault, since some data structures aren't
supposed to be used during connection finalization. Particularly,
the waiting queue can contain already freed streams, so the
WINDOW_UPDATE frame received by that moment could trigger
accessing to these freed streams.
Now, the connection error flag is explicitly checked in
ngx_http_v2_handle_connection_handler().
author | Valentin Bartenev <vbart@nginx.com> |
---|---|
date | Wed, 29 Mar 2017 20:21:01 +0300 |
parents | 2cd019520210 |
children | fa0e093b64d7 |
line wrap: on
line source
/* * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #define NGX_SYSLOG_MAX_STR \ NGX_MAX_ERROR_STR + sizeof("<255>Jan 01 00:00:00 ") - 1 \ + (NGX_MAXHOSTNAMELEN - 1) + 1 /* space */ \ + 32 /* tag */ + 2 /* colon, space */ static char *ngx_syslog_parse_args(ngx_conf_t *cf, ngx_syslog_peer_t *peer); static ngx_int_t ngx_syslog_init_peer(ngx_syslog_peer_t *peer); static void ngx_syslog_cleanup(void *data); static char *facilities[] = { "kern", "user", "mail", "daemon", "auth", "intern", "lpr", "news", "uucp", "clock", "authpriv", "ftp", "ntp", "audit", "alert", "cron", "local0", "local1", "local2", "local3", "local4", "local5", "local6", "local7", NULL }; /* note 'error/warn' like in nginx.conf, not 'err/warning' */ static char *severities[] = { "emerg", "alert", "crit", "error", "warn", "notice", "info", "debug", NULL }; static ngx_log_t ngx_syslog_dummy_log; static ngx_event_t ngx_syslog_dummy_event; char * ngx_syslog_process_conf(ngx_conf_t *cf, ngx_syslog_peer_t *peer) { peer->pool = cf->pool; peer->facility = NGX_CONF_UNSET_UINT; peer->severity = NGX_CONF_UNSET_UINT; if (ngx_syslog_parse_args(cf, peer) != NGX_CONF_OK) { return NGX_CONF_ERROR; } if (peer->server.sockaddr == NULL) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "no syslog server specified"); return NGX_CONF_ERROR; } if (peer->facility == NGX_CONF_UNSET_UINT) { peer->facility = 23; /* local7 */ } if (peer->severity == NGX_CONF_UNSET_UINT) { peer->severity = 6; /* info */ } if (peer->tag.data == NULL) { ngx_str_set(&peer->tag, "nginx"); } peer->conn.fd = (ngx_socket_t) -1; return NGX_CONF_OK; } static char * ngx_syslog_parse_args(ngx_conf_t *cf, ngx_syslog_peer_t *peer) { u_char *p, *comma, c; size_t len; ngx_str_t *value; ngx_url_t u; ngx_uint_t i; value = cf->args->elts; p = value[1].data + sizeof("syslog:") - 1; for ( ;; ) { comma = (u_char *) ngx_strchr(p, ','); if (comma != NULL) { len = comma - p; *comma = '\0'; } else { len = value[1].data + value[1].len - p; } if (ngx_strncmp(p, "server=", 7) == 0) { if (peer->server.sockaddr != NULL) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate syslog \"server\""); return NGX_CONF_ERROR; } ngx_memzero(&u, sizeof(ngx_url_t)); u.url.data = p + 7; u.url.len = len - 7; u.default_port = 514; if (ngx_parse_url(cf->pool, &u) != NGX_OK) { if (u.err) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "%s in syslog server \"%V\"", u.err, &u.url); } return NGX_CONF_ERROR; } peer->server = u.addrs[0]; } else if (ngx_strncmp(p, "facility=", 9) == 0) { if (peer->facility != NGX_CONF_UNSET_UINT) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate syslog \"facility\""); return NGX_CONF_ERROR; } for (i = 0; facilities[i] != NULL; i++) { if (ngx_strcmp(p + 9, facilities[i]) == 0) { peer->facility = i; goto next; } } ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unknown syslog facility \"%s\"", p + 9); return NGX_CONF_ERROR; } else if (ngx_strncmp(p, "severity=", 9) == 0) { if (peer->severity != NGX_CONF_UNSET_UINT) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate syslog \"severity\""); return NGX_CONF_ERROR; } for (i = 0; severities[i] != NULL; i++) { if (ngx_strcmp(p + 9, severities[i]) == 0) { peer->severity = i; goto next; } } ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unknown syslog severity \"%s\"", p + 9); return NGX_CONF_ERROR; } else if (ngx_strncmp(p, "tag=", 4) == 0) { if (peer->tag.data != NULL) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate syslog \"tag\""); return NGX_CONF_ERROR; } /* * RFC 3164: the TAG is a string of ABNF alphanumeric characters * that MUST NOT exceed 32 characters. */ if (len - 4 > 32) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "syslog tag length exceeds 32"); return NGX_CONF_ERROR; } for (i = 4; i < len; i++) { c = ngx_tolower(p[i]); if (c < '0' || (c > '9' && c < 'a' && c != '_') || c > 'z') { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "syslog \"tag\" only allows " "alphanumeric characters " "and underscore"); return NGX_CONF_ERROR; } } peer->tag.data = p + 4; peer->tag.len = len - 4; } else if (len == 10 && ngx_strncmp(p, "nohostname", 10) == 0) { peer->nohostname = 1; } else { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unknown syslog parameter \"%s\"", p); return NGX_CONF_ERROR; } next: if (comma == NULL) { break; } p = comma + 1; } return NGX_CONF_OK; } u_char * ngx_syslog_add_header(ngx_syslog_peer_t *peer, u_char *buf) { ngx_uint_t pri; pri = peer->facility * 8 + peer->severity; if (peer->nohostname) { return ngx_sprintf(buf, "<%ui>%V %V: ", pri, &ngx_cached_syslog_time, &peer->tag); } return ngx_sprintf(buf, "<%ui>%V %V %V: ", pri, &ngx_cached_syslog_time, &ngx_cycle->hostname, &peer->tag); } void ngx_syslog_writer(ngx_log_t *log, ngx_uint_t level, u_char *buf, size_t len) { u_char *p, msg[NGX_SYSLOG_MAX_STR]; ngx_uint_t head_len; ngx_syslog_peer_t *peer; peer = log->wdata; if (peer->busy) { return; } peer->busy = 1; peer->severity = level - 1; p = ngx_syslog_add_header(peer, msg); head_len = p - msg; len -= NGX_LINEFEED_SIZE; if (len > NGX_SYSLOG_MAX_STR - head_len) { len = NGX_SYSLOG_MAX_STR - head_len; } p = ngx_snprintf(p, len, "%s", buf); (void) ngx_syslog_send(peer, msg, p - msg); peer->busy = 0; } ssize_t ngx_syslog_send(ngx_syslog_peer_t *peer, u_char *buf, size_t len) { ssize_t n; if (peer->conn.fd == (ngx_socket_t) -1) { if (ngx_syslog_init_peer(peer) != NGX_OK) { return NGX_ERROR; } } /* log syslog socket events with valid log */ peer->conn.log = ngx_cycle->log; if (ngx_send) { n = ngx_send(&peer->conn, buf, len); } else { /* event module has not yet set ngx_io */ n = ngx_os_io.send(&peer->conn, buf, len); } #if (NGX_HAVE_UNIX_DOMAIN) if (n == NGX_ERROR && peer->server.sockaddr->sa_family == AF_UNIX) { if (ngx_close_socket(peer->conn.fd) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, ngx_close_socket_n " failed"); } peer->conn.fd = (ngx_socket_t) -1; } #endif return n; } static ngx_int_t ngx_syslog_init_peer(ngx_syslog_peer_t *peer) { ngx_socket_t fd; ngx_pool_cleanup_t *cln; peer->conn.read = &ngx_syslog_dummy_event; peer->conn.write = &ngx_syslog_dummy_event; ngx_syslog_dummy_event.log = &ngx_syslog_dummy_log; fd = ngx_socket(peer->server.sockaddr->sa_family, SOCK_DGRAM, 0); if (fd == (ngx_socket_t) -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, ngx_socket_n " failed"); return NGX_ERROR; } if (ngx_nonblocking(fd) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, ngx_nonblocking_n " failed"); goto failed; } if (connect(fd, peer->server.sockaddr, peer->server.socklen) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, "connect() failed"); goto failed; } cln = ngx_pool_cleanup_add(peer->pool, 0); if (cln == NULL) { goto failed; } cln->data = peer; cln->handler = ngx_syslog_cleanup; peer->conn.fd = fd; /* UDP sockets are always ready to write */ peer->conn.write->ready = 1; return NGX_OK; failed: if (ngx_close_socket(fd) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, ngx_close_socket_n " failed"); } return NGX_ERROR; } static void ngx_syslog_cleanup(void *data) { ngx_syslog_peer_t *peer = data; /* prevents further use of this peer */ peer->busy = 1; if (peer->conn.fd == (ngx_socket_t) -1) { return; } if (ngx_close_socket(peer->conn.fd) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, ngx_close_socket_n " failed"); } }