Mercurial > hg > nginx-quic
view src/stream/ngx_stream_upstream_zone_module.c @ 7119:fef61d26da39
Fixed buffer overread with unix sockets after accept().
Some OSes (notably macOS, NetBSD, and Solaris) allow unix socket addresses
larger than struct sockaddr_un. Moreover, some of them (macOS, Solaris)
return socklen of the socket address before it was truncated to fit the
buffer provided. As such, on these systems socklen must not be used without
additional check that it is within the buffer provided.
Appropriate checks added to ngx_event_accept() (after accept()),
ngx_event_recvmsg() (after recvmsg()), and ngx_set_inherited_sockets()
(after getsockname()).
We also obtain socket addresses via getsockname() in
ngx_connection_local_sockaddr(), but it does not need any checks as
it is only used for INET and INET6 sockets (as there can be no
wildcard unix sockets).
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Wed, 04 Oct 2017 21:19:33 +0300 |
parents | 3b1b81e248bc |
children |
line wrap: on
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/* * Copyright (C) Ruslan Ermilov * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_stream.h> static char *ngx_stream_upstream_zone(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_int_t ngx_stream_upstream_init_zone(ngx_shm_zone_t *shm_zone, void *data); static ngx_stream_upstream_rr_peers_t *ngx_stream_upstream_zone_copy_peers( ngx_slab_pool_t *shpool, ngx_stream_upstream_srv_conf_t *uscf); static ngx_stream_upstream_rr_peer_t *ngx_stream_upstream_zone_copy_peer( ngx_stream_upstream_rr_peers_t *peers, ngx_stream_upstream_rr_peer_t *src); static ngx_command_t ngx_stream_upstream_zone_commands[] = { { ngx_string("zone"), NGX_STREAM_UPS_CONF|NGX_CONF_TAKE12, ngx_stream_upstream_zone, 0, 0, NULL }, ngx_null_command }; static ngx_stream_module_t ngx_stream_upstream_zone_module_ctx = { NULL, /* preconfiguration */ NULL, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL /* merge server configuration */ }; ngx_module_t ngx_stream_upstream_zone_module = { NGX_MODULE_V1, &ngx_stream_upstream_zone_module_ctx, /* module context */ ngx_stream_upstream_zone_commands, /* module directives */ NGX_STREAM_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 char * ngx_stream_upstream_zone(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ssize_t size; ngx_str_t *value; ngx_stream_upstream_srv_conf_t *uscf; ngx_stream_upstream_main_conf_t *umcf; uscf = ngx_stream_conf_get_module_srv_conf(cf, ngx_stream_upstream_module); umcf = ngx_stream_conf_get_module_main_conf(cf, ngx_stream_upstream_module); value = cf->args->elts; if (!value[1].len) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid zone name \"%V\"", &value[1]); return NGX_CONF_ERROR; } if (cf->args->nelts == 3) { size = ngx_parse_size(&value[2]); if (size == NGX_ERROR) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid zone size \"%V\"", &value[2]); return NGX_CONF_ERROR; } if (size < (ssize_t) (8 * ngx_pagesize)) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "zone \"%V\" is too small", &value[1]); return NGX_CONF_ERROR; } } else { size = 0; } uscf->shm_zone = ngx_shared_memory_add(cf, &value[1], size, &ngx_stream_upstream_module); if (uscf->shm_zone == NULL) { return NGX_CONF_ERROR; } uscf->shm_zone->init = ngx_stream_upstream_init_zone; uscf->shm_zone->data = umcf; uscf->shm_zone->noreuse = 1; return NGX_CONF_OK; } static ngx_int_t ngx_stream_upstream_init_zone(ngx_shm_zone_t *shm_zone, void *data) { size_t len; ngx_uint_t i; ngx_slab_pool_t *shpool; ngx_stream_upstream_rr_peers_t *peers, **peersp; ngx_stream_upstream_srv_conf_t *uscf, **uscfp; ngx_stream_upstream_main_conf_t *umcf; shpool = (ngx_slab_pool_t *) shm_zone->shm.addr; umcf = shm_zone->data; uscfp = umcf->upstreams.elts; if (shm_zone->shm.exists) { peers = shpool->data; for (i = 0; i < umcf->upstreams.nelts; i++) { uscf = uscfp[i]; if (uscf->shm_zone != shm_zone) { continue; } uscf->peer.data = peers; peers = peers->zone_next; } return NGX_OK; } len = sizeof(" in upstream zone \"\"") + shm_zone->shm.name.len; shpool->log_ctx = ngx_slab_alloc(shpool, len); if (shpool->log_ctx == NULL) { return NGX_ERROR; } ngx_sprintf(shpool->log_ctx, " in upstream zone \"%V\"%Z", &shm_zone->shm.name); /* copy peers to shared memory */ peersp = (ngx_stream_upstream_rr_peers_t **) (void *) &shpool->data; for (i = 0; i < umcf->upstreams.nelts; i++) { uscf = uscfp[i]; if (uscf->shm_zone != shm_zone) { continue; } peers = ngx_stream_upstream_zone_copy_peers(shpool, uscf); if (peers == NULL) { return NGX_ERROR; } *peersp = peers; peersp = &peers->zone_next; } return NGX_OK; } static ngx_stream_upstream_rr_peers_t * ngx_stream_upstream_zone_copy_peers(ngx_slab_pool_t *shpool, ngx_stream_upstream_srv_conf_t *uscf) { ngx_str_t *name; ngx_stream_upstream_rr_peer_t *peer, **peerp; ngx_stream_upstream_rr_peers_t *peers, *backup; peers = ngx_slab_alloc(shpool, sizeof(ngx_stream_upstream_rr_peers_t)); if (peers == NULL) { return NULL; } ngx_memcpy(peers, uscf->peer.data, sizeof(ngx_stream_upstream_rr_peers_t)); name = ngx_slab_alloc(shpool, sizeof(ngx_str_t)); if (name == NULL) { return NULL; } name->data = ngx_slab_alloc(shpool, peers->name->len); if (name->data == NULL) { return NULL; } ngx_memcpy(name->data, peers->name->data, peers->name->len); name->len = peers->name->len; peers->name = name; peers->shpool = shpool; for (peerp = &peers->peer; *peerp; peerp = &peer->next) { /* pool is unlocked */ peer = ngx_stream_upstream_zone_copy_peer(peers, *peerp); if (peer == NULL) { return NULL; } *peerp = peer; } if (peers->next == NULL) { goto done; } backup = ngx_slab_alloc(shpool, sizeof(ngx_stream_upstream_rr_peers_t)); if (backup == NULL) { return NULL; } ngx_memcpy(backup, peers->next, sizeof(ngx_stream_upstream_rr_peers_t)); backup->name = name; backup->shpool = shpool; for (peerp = &backup->peer; *peerp; peerp = &peer->next) { /* pool is unlocked */ peer = ngx_stream_upstream_zone_copy_peer(backup, *peerp); if (peer == NULL) { return NULL; } *peerp = peer; } peers->next = backup; done: uscf->peer.data = peers; return peers; } static ngx_stream_upstream_rr_peer_t * ngx_stream_upstream_zone_copy_peer(ngx_stream_upstream_rr_peers_t *peers, ngx_stream_upstream_rr_peer_t *src) { ngx_slab_pool_t *pool; ngx_stream_upstream_rr_peer_t *dst; pool = peers->shpool; dst = ngx_slab_calloc_locked(pool, sizeof(ngx_stream_upstream_rr_peer_t)); if (dst == NULL) { return NULL; } if (src) { ngx_memcpy(dst, src, sizeof(ngx_stream_upstream_rr_peer_t)); dst->sockaddr = NULL; dst->name.data = NULL; dst->server.data = NULL; } dst->sockaddr = ngx_slab_calloc_locked(pool, sizeof(ngx_sockaddr_t)); if (dst->sockaddr == NULL) { goto failed; } dst->name.data = ngx_slab_calloc_locked(pool, NGX_SOCKADDR_STRLEN); if (dst->name.data == NULL) { goto failed; } if (src) { ngx_memcpy(dst->sockaddr, src->sockaddr, src->socklen); ngx_memcpy(dst->name.data, src->name.data, src->name.len); dst->server.data = ngx_slab_alloc_locked(pool, src->server.len); if (dst->server.data == NULL) { goto failed; } ngx_memcpy(dst->server.data, src->server.data, src->server.len); } return dst; failed: if (dst->server.data) { ngx_slab_free_locked(pool, dst->server.data); } if (dst->name.data) { ngx_slab_free_locked(pool, dst->name.data); } if (dst->sockaddr) { ngx_slab_free_locked(pool, dst->sockaddr); } ngx_slab_free_locked(pool, dst); return NULL; }