bin/40943: amd frequently dumps core

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

>Number:         40943
>Category:       bin
>Synopsis:       amd frequently dumps core
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    bin-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Mar 02 09:05:00 +0000 2009
>Originator:     Hauke Fath <hf%spg.tu-darmstadt.de@localhost>
>Release:        NetBSD 5.0_RC2
>Organization:
-- 
     The ASCII Ribbon Campaign                    Hauke Fath
()     No HTML/RTF in email             Institut für Nachrichtentechnik
/\     No Word docs in email                     TU Darmstadt
     Respect for open standards              Ruf +49-6151-16-3281
>Environment:
        
        
System: NetBSD Gstoder 5.0_RC2 NetBSD 5.0_RC2 (GENERIC) #0: Tue Feb 24 13:00:28 
CET 2009 
hf@Hochstuhl:/var/obj/netbsd-builds/5/i386/sys/arch/i386/compile/GENERIC i386
Architecture: i386
Machine: i386
>Description:

        On a 5.0rc2 machine, amd sooner or later dumps core, leaving the
        machine which auto mounts its home directories practically
        useless till the next reboot.

        Another example: Building packages through

<snip from /etc/mk.conf>
# Since unionfs behaves increasingly dodgy, use a read-only 
# source tree through amd.

PKGSRCDIR =             /misc/netbsd-current/pkgsrc
DISTDIR =               /misc/pkg-distfiles
WRKOBJDIR =             /var/obj/pkgsrc
PACKAGES =              ${WRKOBJDIR}/packages
</snip>

amd won't make it through www/firefox3. 

The whole setup runs just fine with netbsd-3, netbsd-4 and Debian 4
machines.
  
>How-To-Repeat:

        Set up amd on a netbsd-5 machine.

/etc/amd.conf

# $Id: amd.conf,v 1.7 2006/02/20 10:40:41 hf Exp $
#
# From NetBSD: amd.conf,v 1.1 2000/11/20 00:46:09 wiz Exp
#
# Example main config file for amd(8), for details see amd.conf(5).
# Goes into /etc, while cd & net go into /etc/amd (or change paths below).


# GLOBAL OPTIONS SECTION

[ global ]
dismount_interval =     600
auto_dir =              /amd
pid_file =              /var/run/amd.pid
restart_mounts =        yes
unmount_on_exit =       yes
selectors_in_defaults = yes

# See /etc/rc.conf
log_options =           all
log_file =              syslog:local3

map_type =              nis
search_path =           /etc/amd
fully_qualified_hosts =  no


# DEFINE AN AMD MOUNT POINT

[/misc]
browsable_dirs =        yes
map_name =              amd.misc

[ /media ]
browsable_dirs =        no
map_name =              amd.media

[ /home ]
browsable_dirs =        no
map_name =              amd.home

(I can provide the maps if needed.)

[hf@Gstoder] ~ # gdb /usr/sbin/amd /amd.core
GNU gdb 6.5
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i386--netbsdelf"...
Reading symbols from /usr/lib/libamu.so.3...done.
Loaded symbols for /usr/lib/libamu.so.3
Reading symbols from /usr/lib/libldap.so.2...done.
Loaded symbols for /usr/lib/libldap.so.2
Reading symbols from /usr/lib/librpcsvc.so.0...done.
Loaded symbols for /usr/lib/librpcsvc.so.0
Reading symbols from /usr/lib/libc.so.12...done.
Loaded symbols for /usr/lib/libc.so.12
Reading symbols from /usr/lib/liblber.so.2...done.
Loaded symbols for /usr/lib/liblber.so.2
Reading symbols from /usr/lib/libcrypto.so.4...done.
Loaded symbols for /usr/lib/libcrypto.so.4
Reading symbols from /usr/lib/libssl.so.6...done.
Loaded symbols for /usr/lib/libssl.so.6
Reading symbols from /lib/libcrypt.so.0...done.
Loaded symbols for /lib/libcrypt.so.0
Reading symbols from /usr/libexec/ld.elf_so...done.
Loaded symbols for /usr/libexec/ld.elf_so
Core was generated by `amd'.
Program terminated with signal 11, Segmentation fault.
#0  0xbbb32b9b in _malloc_prefork () from /usr/lib/libc.so.12
(gdb) bt
#0  0xbbb32b9b in _malloc_prefork () from /usr/lib/libc.so.12
#1  0xbbb32e1b in free () from /usr/lib/libc.so.12
#2  0x08056707 in mapc_clear (m=0xbb7237e0)
    at /amd/hochstuhl/public/netbsd-5/external/bsd/am-utils/dist/amd/mapc.c:771
#3  0x08056787 in mapc_free (arg=0xbb7237e0)
    at /amd/hochstuhl/public/netbsd-5/external/bsd/am-utils/dist/amd/mapc.c:829
#4  0x0805779b in discard_mntfs (v=0xbb7238d0)
    at /amd/hochstuhl/public/netbsd-5/external/bsd/am-utils/dist/amd/mntfs.c:223
#5  0x08057a59 in flush_mntfs () at 
/amd/hochstuhl/public/netbsd-5/external/bsd/am-utils/dist/amd/mntfs.c:271
#6  0x08058843 in mount_automounter (ppid=223)
    at 
/amd/hochstuhl/public/netbsd-5/external/bsd/am-utils/dist/amd/nfs_start.c:240
#7  0x0804cbda in main (argc=Cannot access memory at address 0xc
) at /amd/hochstuhl/public/netbsd-5/external/bsd/am-utils/dist/amd/amd.c:563
(gdb)

-- I can provide the core file on request.

>Fix:
        Yes, please.

>Unformatted: