nmbd diyng with SIGSEGV on Itanium2

[Miroslav Zubcic]

Jay Fenlason <fenlason at redhat.com> writes:

> This sounds suspiciously like a bug I fixed.  Did you look at
> https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=150582
> and try the rpms I put on people.redhat.com?

I have built RPMS on ia64, but I cannot install them right now (not in
the company's work time, and only one test server is busy, waiting for
a bug manifestation with debigging symbols for Jeremy ...).

OTOH, bug report in https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=150582
is IMHO only /similar/ to my bug. My nmbd(8) does not crash randomly,
but on normal restart - IF and only if it has been up and running for
more than 3 days (default wins TTL?). If I remove wins.dat entries for
a domain, browser, PDC etc, then nmbd is started without SIGSEGV.

Second, internal trace in bug #150582 shows that nmbd is dying in
function "expire_workgroups_and_servers". My nmbd is dying in
"update_name_ttl":

[2005/05/12 10:46:41, 0] lib/util.c:smb_panic2(1512)
  BACKTRACE: 9 stack frames:
   #0 nmbd(smb_panic2-0xa15fe0) [0x2000000800138c10]
   #1 nmbd [0x200000080010e0f0]
   #2 [0xa0000000000107e0]
   #3 nmbd(update_name_ttl-0xaf72c0) [0x2000000800057950]
   #4 nmbd(wins_process_name_registration_request-0xada080) [0x2000000800074ba0]
   #5 nmbd(run_packet_queue-0xaea750) [0x20000008000644e0]
   #6 nmbd(main-0xb0a290) [0x2000000800044610]
   #7 /lib/tls/libc.so.6.1(__libc_start_main-0x56d6f0) [0x20000008005e1550]
   #8 nmbd(_start-0xb0d550) [0x2000000800041700]

I have find one more workaround for this problem: If I set wins TTL to
zero like this:

 "UPRAVA.HAC.HR#00" 0 255.255.255.255 e4R
 "UPRAVA.HAC.HR#1b" 0 10.10.50.30 64R
 "UPRAVA.HAC.HR#1c" 0 10.10.50.30 e4R
 "UPRAVA.HAC.HR#1e" 0 255.255.255.255 e4R

... instead of automatic default:

 "UPRAVA.HAC.HR#00" 1116178439 255.255.255.255 e4R
 "UPRAVA.HAC.HR#1b" 1115876845 10.10.50.30 64R
 "UPRAVA.HAC.HR#1c" 1115876845 10.10.50.30 e4R
 "UPRAVA.HAC.HR#1e" 1116178054 255.255.255.255 e4R

Then, bug is not triggering after 3 days, because i suspect function
update_name_ttl is not used at all, just like when there is no entries
in wins.dat at all.

BTW, I'm using almost vanilla Red Hat samba 3.0.10 SRPM package, but
with one small patch which is not directly connected with this bug:
http://samba.org/~jerry/patches/post-3.0.10/domain_admin-join.patch

As I see now, this important patch doesn't apply on 3.0.13 from
Fenlason's SRPMS - it has *many* rejects. :-( I have picky
customer/firm which has switched from samba Red Hat 8 with samba 2.2
to official RHEL 4 with samba 3, only after this "domain admins join"
functionality was possible thanks to Jerry and his patch. They want to
have per-tehnician account for joining machines in samba domain, not
one - the root, and I cannot convince them to the opposite.


-- 
Miroslav Zubcic, RHCE, Nimium d.o.o., email: <mvz at nimium.hr>