bin/55278: inetd dies while starting Samba smbd

[Hauke Fath <hf%spg.tu-darmstadt.de@localhost>]

>Number:         55278
>Category:       bin
>Synopsis:       inetd dies while starting Samba smbd
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    bin-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue May 19 07:25:00 +0000 2020
>Originator:     Hauke Fath
>Release:        NetBSD 9.0_STABLE
>Organization:
Falling Raindrops
>Environment:
	
	
System: NetBSD pizza.causeuse.org 9.0_STABLE NetBSD 9.0_STABLE (BLACKBOX-$Revision: 1.85 $) #0: Sat May 16 15:16:03 CEST 2020 hauke%pizza.causeuse.org@localhost:/var/obj/netbsd-builds/9/amd64/sys/arch/amd64/compile/BLACKBOX amd64
Architecture: x86_64
Machine: amd64
>Description:

	On a machine that does not see windows clients often, I have
	configured the Samba nmbd and smbd daemons to be started from
	inetd:

netbios-ssn     stream  tcp     nowait  root    /usr/pkg/sbin/smbd smbd
microsoft-ds    stream  tcp     nowait  root    /usr/pkg/sbin/smbd smbd
netbios-ns      dgram   udp     wait    root    /usr/pkg/sbin/nmbd nmbd

	This works fine with a non-detaching inetd ('inetd -d -l'):

# ./inetd -l -d
[...]
ADD : netbios-ssn proto=tcp, wait.max=0.40, user:group=root:(null) builtin=0 server=/usr/pkg/sbin/smbd policy=
registered /usr/pkg/sbin/smbd on 20
ADD : microsoft-ds proto=tcp, wait.max=0.40, user:group=root:(null) builtin=0 server=/usr/pkg/sbin/smbd policy=
registered /usr/pkg/sbin/smbd on 21
ADD : netbios-ns proto=udp, wait.max=1.40, user:group=root:(null) builtin=0 server=/usr/pkg/sbin/nmbd policy=
registered /usr/pkg/sbin/nmbd on 22
someone wants microsoft-ds
accept, ctrl 5
someone wants microsoft-ds
accept, ctrl 5
8493 execl /usr/pkg/sbin/smbd
2551 execl /usr/pkg/sbin/smbd
8493 reaped, status 0xf
2551 reaped, status 0xf

	But a daemonized inetd terminates while starting smbd:

[inetd built with -O -g3]

(gdb) attach 1525
Attaching to process 1525
Reading symbols from /u1/netbsd-9/src/usr.sbin/inetd/./inetd...
Reading symbols from /usr/lib/libwrap.so.1...
(No debugging symbols found in /usr/lib/libwrap.so.1)
Reading symbols from /usr/lib/libutil.so.7...
(No debugging symbols found in /usr/lib/libutil.so.7)
Reading symbols from /usr/lib/libipsec.so.3...
(No debugging symbols found in /usr/lib/libipsec.so.3)
Reading symbols from /usr/lib/libc.so.12...
(No debugging symbols found in /usr/lib/libc.so.12)
Reading symbols from /usr/libexec/ld.elf_so...
(No debugging symbols found in /usr/libexec/ld.elf_so)
[Switching to LWP 1 of process 1525]
0x000074691e042b3a in _sys___kevent50 () from /usr/lib/libc.so.12
(gdb) continue
Continuing.
[New process 1525]
[Detaching after fork from child process 2295]
[Detaching after fork from child process 8237]

Thread 2 "" received signal SIGTERM, Terminated.
[Switching to process 1525]
0x000074691e0427fa in _sys___sigprocmask14 () from /usr/lib/libc.so.12
(gdb) bt
#0  0x000074691e0427fa in _sys___sigprocmask14 () from /usr/lib/libc.so.12
#1  0x000074691e11d13f in clnt_vc_create () from /usr/lib/libc.so.12
#2  0x000074691e113ef2 in ?? () from /usr/lib/libc.so.12
#3  0x000074691e1142cb in rpcb_unset () from /usr/lib/libc.so.12
#4  0x0000000099603ad4 in unregister_rpc (sep=0x74691f1f5d00) at inetd.c:1211
#5  0x0000000099605d2c in goaway () at inetd.c:1028
#6  main (argc=<optimized out>, argv=<optimized out>) at inetd.c:515
(gdb) 

%  head -1 inetd.c
/*	$NetBSD: inetd.c,v 1.125 2017/11/28 11:51:11 martin Exp $	*/
%
	
>How-To-Repeat:

	Run Samba 4 smbd from inetd: Connecting clients will error
	out, and the server's inetd will vanish in thin air. No
	related log entries anywhere.

	
>Fix:
	
	No idea...

>Unformatted: