[CentOS] Apache umask

Mon Jul 20 05:41:09 UTC 2020
Simon Matter <simon.matter at invoca.ch>

> On 7/13/20 6:40 PM, Emmett Culley via CentOS wrote:
>> I need to set the umask for apache to 002.  I've tried every idea I've
>> found on the internet, but nothing make a difference.  Most suggest that
>> I put "umask 002" in /etc/sysconfig/httpd, but that doesn't seem to make
>> a difference.  Other's suggest adding something to the httpd.service
>> script for systemd.  And that doesn't make any difference.
>
> I had a couple sideline emails with Emmett about suexec possibly being the
> culprit.  TL;DR: that's not it.
>
> The apache suexec utility can enforce a umask (typically 022) on CGI and
> SSI (server-side includes).  Taking a look at the source in
> support/suexec.c, if compiled with AP_SUEXEC_UMASK set to some value, it
> will set the umask; else there is no umask change.  AP_SUEXEC_UMASK is set
> via ./configure with --with-suexec-umask.
>
> In CentOS 8 httpd-2.4.37-21.module_el8.2.0+382+15b0afa8.src.rpm the
> httpd.spec for ./configure with suexec-related configuration flags are
> notably absent of --with-suexec-umask.  I also did a prep of the sources
> and no patches modify the suexec sources in this way. 

I may have missed something but it seems to work in my test:

# grep -i umask /proc/<http_worker>/status
Umask:	0022

# cat /etc/systemd/system/httpd.service.d/override.conf
[Service]
UMask=0002

# systemctl edit httpd.service
< enter override config >

<reload/restart httpd>

# grep -i umask /proc/<http_worker>/status
Umask:	0002

That's what you are looking for, isn't it?

I didn't test to write files but at least the umask on the process is set
as it seems.

Regards,
Simon