[Bug]: Master is executing custom grains (maybe intended?)

[Sxderp]

What happened?

I was looking at my master logs and saw some errors related to grains. These showed up because the custom grains assumed running as root (the minions run as root).

Is the master supposed to execute custom grains? I can't think of a reason why the master needs to execute them? I think this is "similar" to #66746 in that the master shouldn't be doing anything with grains, that's for the minion.

I can't find any documentation that says the master process should be executing grains. https://docs.saltproject.io/salt/user-guide/en/latest/topics/grains.html

Setup.

Create a custom grains and make it available in the files repo.

import logging

def __virtual__():
    return True

def custom_grain():
    logging.error('Custom Grain!')
    return {}

Sync the grains (I was initially doing this for renderer stuffs and grains got pulled in).

# change as necessary, we run salt as "salt:salt" so that's who needs to sync
$ sudo -g salt -u salt salt-run saltutil.sync_all
cache:
clouds:
engines:
executors:
fileserver:
grains:
    - grains.custom
modules:
output:
pillar:
proxymodules:
queues:
renderers:
returners:
roster:
runners:
sdb:
serializers:
states:

Restart the master and see the error messages in the log files.

Oct 21 10:53:54 arcs-msalt01.arcs.gatech.edu python3[1788524]: [ERROR   ] Custom Grain!
Oct 21 10:53:54 arcs-msalt01.arcs.gatech.edu python3[1788549]: [ERROR   ] Custom Grain!
Oct 21 10:53:54 arcs-msalt01.arcs.gatech.edu python3[1788552]: [ERROR   ] Custom Grain!
Oct 21 10:53:54 arcs-msalt01.arcs.gatech.edu python3[1788539]: [ERROR   ] Custom Grain!
Oct 21 10:53:54 arcs-msalt01.arcs.gatech.edu python3[1788542]: [ERROR   ] Custom Grain!

Every so often the grains get run again so the errors keep coming up. I'm guessing the master is also on a grain refresh cycle like the minion.

Type of salt install

Official rpm

Major version

3007.x

What supported OS are you seeing the problem on? Can select multiple. (If bug appears on an unsupported OS, please open a GitHub Discussion instead)

rhel-9

salt --versions-report output

Salt Version:
          Salt: 3007.8
 
Python Version:
        Python: 3.10.18 (main, Sep  5 2025, 22:48:51) [GCC 11.2.0]
 
Dependency Versions:
          cffi: 1.16.0
      cherrypy: unknown
  cryptography: 42.0.5
      dateutil: 2.8.2
     docker-py: Not Installed
         gitdb: Not Installed
     gitpython: Not Installed
        Jinja2: 3.1.6
       libgit2: Not Installed
  looseversion: 1.3.0
      M2Crypto: Not Installed
          Mako: Not Installed
       msgpack: 1.0.7
  msgpack-pure: Not Installed
  mysql-python: Not Installed
     packaging: 24.0
     pycparser: 2.21
      pycrypto: Not Installed
  pycryptodome: 3.19.1
        pygit2: Not Installed
  python-gnupg: 0.5.2
        PyYAML: 6.0.1
         PyZMQ: 25.1.2
        relenv: 0.20.6
         smmap: Not Installed
       timelib: 0.3.0
       Tornado: 6.4.2
           ZMQ: 4.3.4
 
Salt Package Information:
  Package Type: onedir
 
System Versions:
          dist: rhel 9.6 Plow
        locale: utf-8
       machine: x86_64
       release: 5.14.0-570.41.1.el9_6.x86_64
        system: Linux
       version: Red Hat Enterprise Linux 9.6 Plow