[PATCH] Cache messaging dgm connections

[Andreas Schneider]

On Saturday, 17 September 2016 22:17:00 CEST Ralph Böhme wrote:
> On Sat, Sep 17, 2016 at 01:17:55PM +0200, Andreas Schneider wrote:
> > On Friday, 16 September 2016 14:03:42 CEST Jeremy Allison wrote:
> > > Still got the crash with this in autobuild, now with the backtrace
> > > below. So we're still not catching everything (or something else
> > > is freeing ev behind our backs :-).
> > > 
> > > As I know we're going to be co-located on Monday, let's
> > > schedule a time to look at this directly at the SNIA
> > > conf.
> > 
> > This looks like a bug report in Fedora with Samba 4.5.0. smbd directly
> > segfaults at startup!
> > 
> > Backtrace and core file is attached to the bug. We have this since rc1.
> > 
> > https://bugzilla.redhat.com/show_bug.cgi?id=1375973
> 
> this looks like a different issue.

Are you sure? The code looks like this:

1 void tevent_debug(struct tevent_context *ev, enum tevent_debug_level level,
2                   const char *fmt, ...)
3 {
4        va_list ap;
5        if (!ev) {
6                return;
7        }
8        if (ev->debug_ops.debug == NULL) {

In line 5 the ev was a valid pointer and in line 8 we fail to derefence it and 
segfault. This either means the pointer ev was freed berween line 5 and 8 or 
the pointer has been freed before but not set to NULL.


smbd_notifyd_init() segfaults at smbd startup!