svn commit: r230869 - head/usr.sbin/daemon

[Andrey Zonov]

On 04.02.2012 11:42, Pawel Jakub Dawidek wrote:
> On Wed, Feb 01, 2012 at 04:41:00PM +0000, Guy Helmer wrote:
>> Author: ghelmer
>> Date: Wed Feb  1 16:40:59 2012
>> New Revision: 230869
>> URL: http://svn.freebsd.org/changeset/base/230869
>>
>> Log:
>>    Change the notes about the pidfile to include Doug's preference
>>    for pre-creating the pidfile with appropriate owner and permissions.
>>
>>    Requested by dougb
>
> Pre-creating pidfiles? That sounds weird. The common practise is to turn
> eg. /var/run/<name>.pid into /var/run/<name>/pid where<name>  directory
> has appropriate permissions. Pre-creating pidfiles is simply wrong,
> because applications create pidfile on start and unlink it on exit.
> If application has no permission to remove files from /var/run/ it will
> leave pidfile with stale PID in it, which is bad. Changing application
> to truncate pidfile on exit instead of unlinking it also is a bad idea
> especially because there is working solution - pid directory.
>

Hi,

There's even worse problem - kernel closes pidfile in execvp() because 
of FD_CLOEXEC flag is set and daemon doesn't hold lock on pidfile.

I reported about that earlier, but was ignored.


-- 
Andrey Zonov