See responses below. On Wednesday, April 24, 2019 6:13:51 AM PDT Jonathan Billings wrote: > On Tue, Apr 23, 2019 at 11:37:51PM -0700, Benjamin Smith wrote: > > But... php-fpm has its own "tmp" directory, something like /tmp/systemd- > > private-RANDOM-php-fpm.service-RANDOM/tmp that the cgi-bin has no access > > to. To be able to populate $_FILES in a way compatible with the rest of > > the framework, it appears that I need to be able to run the /cgi-bin in > > the same context as the php-fpm environment so files can be access across > > all the different parts of the web app. This includes related things like > > access to the $_SESSION data files, and so on. > > Don't share data between services with /tmp. I'm not trying to share data between services with /tmp. I'm trying to share services with the sandboxed /tmp provided by systemd. > Create a separate directory to share data, make sure the permissions > and SELinux attributes allow writing there. Put it in > /run/yourservice/ if you want it to be ephemeral and small. Already done for the instance of php-fpm running. I need access to that security context from within the cgi-bin script that runs as a shell script fork under Apache. > The reason why the php-fpm service has its own private /tmp directory > is because the php-fpm.service has "PrivateTmp=true" in its [Service] > section. This creates a private /tmp namespace for the php-fpm > process, which is a good security practice. Yep. Not trying to expand the security footprint any more than absolutely necessary. > If you absolutely must share files via /tmp, you'll have to create an > /etc/systemd/system/php-fpm.service.d/override.conf that has a > [Service] section that says PrivateTmp=false. It's a bad idea and > you're actually lowering the security of your system by doing it. ... which is why I'm not trying to do that. I want to *share* systemd's security context. There's another way to go using a shared socket service, but it's messy and complicated - never a good idea when security is a primary concern.