Mercurial > hg > nginx
view src/stream/ngx_stream_set_module.c @ 8106:8852f39311de
Fixed segfault when switching off master process during upgrade.
Binary upgrades are not supported without master process, but it is,
however, possible, that nginx running with master process is asked
to upgrade binary, and the configuration file as available on disk
at this time includes "master_process off;".
If this happens, listening sockets inherited from the previous binary
will have ls[i].previous set. But the old cycle on initial process
startup, including startup after binary upgrade, is destroyed by
ngx_init_cycle() once configuration parsing is complete. As a result,
an attempt to dereference ls[i].previous in ngx_event_process_init()
accesses already freed memory.
Fix is to avoid looking into ls[i].previous if the old cycle is already
freed.
With this change it is also no longer needed to clear ls[i].previous in
worker processes, so the relevant code was removed.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Wed, 23 Nov 2022 23:48:53 +0300 |
parents | 45e9281c6c5b |
children |
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/* * Copyright (C) Pavel Pautov * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_stream.h> typedef struct { ngx_int_t index; ngx_stream_set_variable_pt set_handler; uintptr_t data; ngx_stream_complex_value_t value; } ngx_stream_set_cmd_t; typedef struct { ngx_array_t commands; } ngx_stream_set_srv_conf_t; static ngx_int_t ngx_stream_set_handler(ngx_stream_session_t *s); static ngx_int_t ngx_stream_set_var(ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data); static ngx_int_t ngx_stream_set_init(ngx_conf_t *cf); static void *ngx_stream_set_create_srv_conf(ngx_conf_t *cf); static char *ngx_stream_set(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_command_t ngx_stream_set_commands[] = { { ngx_string("set"), NGX_STREAM_SRV_CONF|NGX_CONF_TAKE2, ngx_stream_set, NGX_STREAM_SRV_CONF_OFFSET, 0, NULL }, ngx_null_command }; static ngx_stream_module_t ngx_stream_set_module_ctx = { NULL, /* preconfiguration */ ngx_stream_set_init, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ ngx_stream_set_create_srv_conf, /* create server configuration */ NULL /* merge server configuration */ }; ngx_module_t ngx_stream_set_module = { NGX_MODULE_V1, &ngx_stream_set_module_ctx, /* module context */ ngx_stream_set_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 ngx_int_t ngx_stream_set_handler(ngx_stream_session_t *s) { ngx_str_t str; ngx_uint_t i; ngx_stream_set_cmd_t *cmds; ngx_stream_set_srv_conf_t *scf; ngx_stream_variable_value_t vv; scf = ngx_stream_get_module_srv_conf(s, ngx_stream_set_module); cmds = scf->commands.elts; vv = ngx_stream_variable_null_value; for (i = 0; i < scf->commands.nelts; i++) { if (ngx_stream_complex_value(s, &cmds[i].value, &str) != NGX_OK) { return NGX_ERROR; } if (cmds[i].set_handler != NULL) { vv.len = str.len; vv.data = str.data; cmds[i].set_handler(s, &vv, cmds[i].data); } else { s->variables[cmds[i].index].len = str.len; s->variables[cmds[i].index].valid = 1; s->variables[cmds[i].index].no_cacheable = 0; s->variables[cmds[i].index].not_found = 0; s->variables[cmds[i].index].data = str.data; } } return NGX_DECLINED; } static ngx_int_t ngx_stream_set_var(ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data) { *v = ngx_stream_variable_null_value; return NGX_OK; } static ngx_int_t ngx_stream_set_init(ngx_conf_t *cf) { ngx_stream_handler_pt *h; ngx_stream_core_main_conf_t *cmcf; cmcf = ngx_stream_conf_get_module_main_conf(cf, ngx_stream_core_module); h = ngx_array_push(&cmcf->phases[NGX_STREAM_PREACCESS_PHASE].handlers); if (h == NULL) { return NGX_ERROR; } *h = ngx_stream_set_handler; return NGX_OK; } static void * ngx_stream_set_create_srv_conf(ngx_conf_t *cf) { ngx_stream_set_srv_conf_t *conf; conf = ngx_pcalloc(cf->pool, sizeof(ngx_stream_set_srv_conf_t)); if (conf == NULL) { return NULL; } /* * set by ngx_pcalloc(): * * conf->commands = { NULL }; */ return conf; } static char * ngx_stream_set(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_stream_set_srv_conf_t *scf = conf; ngx_str_t *args; ngx_int_t index; ngx_stream_set_cmd_t *set_cmd; ngx_stream_variable_t *v; ngx_stream_compile_complex_value_t ccv; args = cf->args->elts; if (args[1].data[0] != '$') { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid variable name \"%V\"", &args[1]); return NGX_CONF_ERROR; } args[1].len--; args[1].data++; v = ngx_stream_add_variable(cf, &args[1], NGX_STREAM_VAR_CHANGEABLE|NGX_STREAM_VAR_WEAK); if (v == NULL) { return NGX_CONF_ERROR; } index = ngx_stream_get_variable_index(cf, &args[1]); if (index == NGX_ERROR) { return NGX_CONF_ERROR; } if (v->get_handler == NULL) { v->get_handler = ngx_stream_set_var; } if (scf->commands.elts == NULL) { if (ngx_array_init(&scf->commands, cf->pool, 1, sizeof(ngx_stream_set_cmd_t)) != NGX_OK) { return NGX_CONF_ERROR; } } set_cmd = ngx_array_push(&scf->commands); if (set_cmd == NULL) { return NGX_CONF_ERROR; } set_cmd->index = index; set_cmd->set_handler = v->set_handler; set_cmd->data = v->data; ngx_memzero(&ccv, sizeof(ngx_stream_compile_complex_value_t)); ccv.cf = cf; ccv.value = &args[2]; ccv.complex_value = &set_cmd->value; if (ngx_stream_compile_complex_value(&ccv) != NGX_OK) { return NGX_CONF_ERROR; } return NGX_CONF_OK; }