nginx default unix domain socket permissions and umask

[Maxim Dounin]

Hello!

On Thu, Sep 22, 2016 at 01:12:21PM +0000, Manole, Sorin wrote:

> Hello,
> 
> It seems that when nginx creates unix domain sockets as a result 
> of the listen directive it assigns rw permissions for all users.
> This is probably because the bind() call which creates the file 
> follows the process umask. Nginx sets the umask to 0 which is 
> the most relaxed setting.
> 
> Is there a way to control the permissions assigned at creation 
> to unix domain sockets created by nginx?

I don't think so.

If you want to limit access to unix sockets created by nginx, most 
trivial solution would be to create them in a directory with 
appropriate permissions.

> Is there a deep reason to always set the umask to 0? Would it be 
> better to let the user decide the umask and inherit it from the 
> process starting nginx?

The umask is set to 0 for nginx to be able to control permissions 
when explicitly configured (for example when saving files using 
proxy_store, http://nginx.org/r/proxy_store_access).

-- 
Maxim Dounin
http://nginx.org/