Mercurial > hg > nginx-quic
view src/os/win32/ngx_service.c @ 7054:e02555553d0b
Range filter: protect from total size overflows.
The overflow can be used to circumvent the restriction on total size of
ranges introduced in c2a91088b0c0 (1.1.2). Additionally, overflow
allows producing ranges with negative start (such ranges can be created
by using a suffix, "bytes=-100"; normally this results in 200 due to
the total size check). These can result in the following errors in logs:
[crit] ... pread() ... failed (22: Invalid argument)
[alert] ... sendfile() failed (22: Invalid argument)
When using cache, it can be also used to reveal cache file header.
It is believed that there are no other negative effects, at least with
standard nginx modules.
In theory, this can also result in memory disclosure and/or segmentation
faults if multiple ranges are allowed, and the response is returned in a
single in-memory buffer. This never happens with standard nginx modules
though, as well as known 3rd party modules.
Fix is to properly protect from possible overflow when incrementing size.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Tue, 11 Jul 2017 16:06:23 +0300 |
parents | a1caf3989b49 |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #define NGX_SERVICE_CONTROL_SHUTDOWN 128 #define NGX_SERVICE_CONTROL_REOPEN 129 SERVICE_TABLE_ENTRY st[] = { { "nginx", service_main }, { NULL, NULL } }; ngx_int_t ngx_service(ngx_log_t *log) { /* primary thread */ /* StartServiceCtrlDispatcher() should be called within 30 seconds */ if (StartServiceCtrlDispatcher(st) == 0) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "StartServiceCtrlDispatcher() failed"); return NGX_ERROR; } return NGX_OK; } void service_main(u_int argc, char **argv) { SERVICE_STATUS status; SERVICE_STATUS_HANDLE service; /* thread spawned by SCM */ service = RegisterServiceCtrlHandlerEx("nginx", service_handler, ctx); if (service == INVALID_HANDLE_VALUE) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "RegisterServiceCtrlHandlerEx() failed"); return; } status.dwServiceType = SERVICE_WIN32_OWN_PROCESS; status.dwCurrentState = SERVICE_START_PENDING; status.dwControlsAccepted = SERVICE_ACCEPT_STOP |SERVICE_ACCEPT_PARAMCHANGE; status.dwWin32ExitCode = NO_ERROR; status.dwServiceSpecificExitCode = 0; status.dwCheckPoint = 1; status.dwWaitHint = 2000; /* SetServiceStatus() should be called within 80 seconds */ if (SetServiceStatus(service, &status) == 0) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "SetServiceStatus() failed"); return; } /* init */ status.dwCurrentState = SERVICE_RUNNING; status.dwCheckPoint = 0; status.dwWaitHint = 0; if (SetServiceStatus(service, &status) == 0) { ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "SetServiceStatus() failed"); return; } /* call master or worker loop */ /* * master should use event notification and look status * single should use iocp to get notifications from service handler */ } u_int service_handler(u_int control, u_int type, void *data, void *ctx) { /* primary thread */ switch (control) { case SERVICE_CONTROL_INTERROGATE: status = NGX_IOCP_INTERROGATE; break; case SERVICE_CONTROL_STOP: status = NGX_IOCP_STOP; break; case SERVICE_CONTROL_PARAMCHANGE: status = NGX_IOCP_RECONFIGURE; break; case NGX_SERVICE_CONTROL_SHUTDOWN: status = NGX_IOCP_REOPEN; break; case NGX_SERVICE_CONTROL_REOPEN: status = NGX_IOCP_REOPEN; break; default: return ERROR_CALL_NOT_IMPLEMENTED; } if (ngx_single) { if (PostQueuedCompletionStatus(iocp, ... status, ...) == 0) { err = ngx_errno; ngx_log_error(NGX_LOG_ALERT, log, err, "PostQueuedCompletionStatus() failed"); return err; } } else { Event } return NO_ERROR; }