On Nov 23, 2004, at 4:05 PM, dbw(a)ozreef.org wrote: Yes, that would keep you from accessing /tmp. If the TMP environment variable is not set (or is set to an unreachable directory), and the images subdirectory is not writable, it will try to use /tmp and fail. upload_tmp_dir is not the general /tmp directory; that's where PHP stores files that have been uploaded in an HTTP POST request with attached files. Great! It should probably stay writable; if for instance you update xhtml_slim.pt it will need to recompile the template again. Also you will need that directory (or equivalent) to be writable if you want to enable the upload or TeX rendering features. The compiled template script file itself is safe, it's a PHP file that simply defines a function and so shouldn't be able to be executed in a malicious manner. If you're on shared hosting and there are other users who can directly access the filesystem from the web server, perhaps by running arbitrary shell commands or CGI scripts (bypassing PHP's safe_mode or open_base_dir restrictions) it's possible that they could write arbitrary files into your writable directory. (They could also read your database password in the config files, whether you have a writable directory or not, if they are able to get direct filesystem access.) Assuming that other protections are in place and open_base_dir is sufficient to prevent access to arbitrary filesystem locations by other users' scripts (it is your hosting provider's job to assure this), then there should not be any real risk. The directions already state that you should make the images directory writable if /tmp doesn't work, but the warning doesn't (yet) trigger on the open_base_dir setting. -- brion vibber (brion @ pobox.com)