[systemd-devel] Antw: Re: Antw: systemd prerelease 243-rc2

[Ulrich Windl]

>>> Mantas Mikulenas <grawity at gmail.com> schrieb am 23.08.2019 um 05:55 in
Nachricht
<CAPWNY8WRWMv4CS_cRoVp20Q_4aXUUp1CUN-XJWoO4+t3xOmFcQ at mail.gmail.com>:
> On Thu, Aug 22, 2019, 16:38 Ulrich Windl
<Ulrich.Windl at rz.uni-regensburg.de>
> wrote:
> 
>> >>> systemd tag bot <donotreply-systemd-tag at refi64.com> schrieb am
>> 22.08.2019
>> um
>> 13:56 in Nachricht <20190822115637.1.05C510C92B339AF7 at refi64.com>:
>> > A new systemd ☠️ pre-release ☠️ has just been tagged. Please download
>> the
>> > tarball here:
>>
>>
>> >         * On 64 bit systems, the "kernel.pid_max" sysctl is now bumped
to
>> >           4194304 by default, i.e. the full 22bit range the kernel
>> allows,
>> > up
>> >           from the old 16bit range. This should improve security and
>> >           robustness, as PID collisions are made less likely (though
>>
>> I doubt it's increasing robustness for any existing application as
>> pid_traditionally was 16 bit. I don't know if some applications try to
>> sprintf() a pid into a char[6], but if they do, it might cause an
>> application
>> failure...
>>
> 
> 
> I've been using this value for at least 5 years, and did expect many issues
> at first, but so far haven't encountered any at all.
> 
> (I do kind of suspect that if there are any programs affected by this and
> without source code available, they would be so old that they wouldn't
> really run on a bleeding-edge distro anyway...)

Having read some C questions in stackoverflow yesterday, I'm afraid there are
quite a lot of programmers out there writing code you couldn't even imagine in
your most terrible nightmares ;-)
So distribution code may be safe, but some in-house stuff or even "commercial"
stuff may be horrible:
(Not to long ago I had a problem that some commercial application only started
up if the text terminal was wider than 80 characters. Why? The C program called
"ps" internally, and that in turn truncated output lines depending on the value
of COLUMNS environment...)

I think you really don't know what the most terrible imaginable programmer can
write... ;-)

Or maybe the infamous Ariane V failure: They reused software they had tested
before, but the hardware was different ;-)

Regards,
Ulrich