[PATCH] Fix smbd crash (valgrind error) if generic memcache evicts share mode entry. BUG: https://bugzilla.samba.org/show_bug.cgi?id=13871

[Jeremy Allison]

On Sat, Mar 30, 2019 at 04:48:19PM -0700, Jeremy Allison via samba-technical wrote:
> On Sat, Mar 30, 2019 at 05:07:01PM +0100, Ralph Böhme wrote:
> > Can you please share the exact steps how to reproduce the isue? Thanks!
> 
> Apply the patch from:
> 
> https://bugzilla.samba.org/show_bug.cgi?id=13865
> 
> (this patch).
> 
> https://attachments.samba.org/attachment.cgi?id=15021
> 
> make, then do:
> 
> $ make test TESTS=samba3.base.rw1
> 
> and you'll get a reliable smbd crash.

Aha. Did some more digging....

Looks like the patch in:

https://bugzilla.samba.org/show_bug.cgi?id=13865
https://attachments.samba.org/attachment.cgi?id=15021

buggers up the memcache sizes, so we try and remove
the entry we're actually adding.

Sorry for the noise :-). Please ignore bug

https://bugzilla.samba.org/show_bug.cgi?id=13871

until I've dug into this some more.

Phew, the logic in the share mode memcache
code is *evil* (and I wrote the bloody thing
back in 2015 :-).

I'm glad it isn't broken :-).