freebsd stable - Jun 2018 - syslogd became silent between 11.2-PRERELEASE r334874 and r335282

Hi Michael,

2018-06-17 17:52 GMT+02:00 Michael Grimm <trashcan at
ellael.org>:
> I do believe that this commit might be the cause:
>
https://svnweb.freebsd.org/base/stable/11/usr.sbin/syslogd/Makefile?revision=335059&view=markup&sortby=file
Thanks for reporting this issue. I just did some debugging on my
system and I think I was able to reproduce this issue. It seems as if
I made a tiny mistake in how I implemented the RFC 5426 UDP message
size limiting. Could you please give the following patch for syslogd a
try?

Index: usr.sbin/syslogd/syslogd.c
==================================================================---
usr.sbin/syslogd/syslogd.c  (revision 334706)
+++ usr.sbin/syslogd/syslogd.c  (working copy)
@@ -1613,8 +1613,8 @@
        struct iovec *last;
        size_t diff;

-       while (size > il->totalsize) {
-               diff = size - il->totalsize;
+       while (il->totalsize > size) {
+               diff = il->totalsize - size;
                last = &il->iov[il->iovcnt - 1];
                if (diff >= last->iov_len) {
                        /* Remove the last iovec entirely. */

It should be sufficient to apply this to just the 'client' syslogd.
There is no need to patch the central (storage) server.

-- 
Ed Schouten <ed at nuxi.nl>
Nuxi, 's-Hertogenbosch, the Netherlands

Hi Ed --
> On 17. Jun 2018, at 19:27, Ed Schouten <ed at nuxi.nl> wrote:
> 
> Hi Michael,
> 
> 2018-06-17 17:52 GMT+02:00 Michael Grimm <trashcan at ellael.org>:
>> I do believe that this commit might be the cause:
>>
https://svnweb.freebsd.org/base/stable/11/usr.sbin/syslogd/Makefile?revision=335059&view=markup&sortby=file
> 
> Thanks for reporting this issue. I just did some debugging on my
> system and I think I was able to reproduce this issue. It seems as if
> I made a tiny mistake in how I implemented the RFC 5426 UDP message
> size limiting. Could you please give the following patch for syslogd a
> try?
> 
> Index: usr.sbin/syslogd/syslogd.c
> ==================================================================> ---
usr.sbin/syslogd/syslogd.c  (revision 334706)
> +++ usr.sbin/syslogd/syslogd.c  (working copy)
> @@ -1613,8 +1613,8 @@
>        struct iovec *last;
>        size_t diff;
> 
> -       while (size > il->totalsize) {
> -               diff = size - il->totalsize;
> +       while (il->totalsize > size) {
> +               diff = il->totalsize - size;
>                last = &il->iov[il->iovcnt - 1];
>                if (diff >= last->iov_len) {
>                        /* Remove the last iovec entirely. */
> 
> It should be sufficient to apply this to just the 'client' syslogd.
> There is no need to patch the central (storage) server.
Sorry for my late response, and: 

Thanks, your patch fixed it!

I am not that much experienced, but that's what I did:

#) svn update -r 335059
#) applied your patch
#) recompiled world and kernel
#) reinstalled world and kernel
#) reinstalled my jail's basejail (ezjail technology)
#) reboot
-> return of syslogd clients being able to send syslog messages from jails to
host's syslogd

I hope that this is sufficient prove that your patch will work?

Thank you very much and with kind regards,
Michael