pkg/54123: crash trying 'pkgin upgrade' with locally built pkg_summary

["Greg A. Woods" <woods%planix.ca@localhost>]

>Number:         54123
>Category:       pkg
>Synopsis:       crash trying 'pkgin upgrade' with locally built pkg_summary
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Apr 14 22:10:00 +0000 2019
>Originator:     Greg A. Woods
>Release:        NetBSD 8.99.32
>Organization:
Planix, Inc.; Kelowna, BC; Canada
>Environment:
System: NetBSD future 8.99.32 NetBSD 8.99.32 (XEN3_DOMU) #0: Mon Feb 4 15:01:05 PST 2019 woods@future:/build/woods/future/current-amd64-amd64-obj/building/work/woods/m-NetBSD-current/sys/arch/amd64/compile/XEN3_DOMU amd64
Architecture: x86_64
Machine: amd64
>Description:

	I had done "pkg_info -X -a | gzip > $PKG_PATH/pkg_summary.gz" on
	the build host, then installed pgkin-0.11.7 on a client host
	(which mounts the build host's packages directory via NFS), then
	this happened:

# pkgin update
cleaning database from ftp://ftp.netbsd.org/pub/pkgsrc/packages/NetBSD/amd64/8.99.32/All entries...
processing remote summary (file:///future/build/packages/root/NetBSD/8.99.32/x86_64/All/)...
pkg_summary.gz                                                                                    100%   69KB  68.6KB/s   00:00    
# pkgin upgrade
calculating dependencies...done.
warning: package automake-1.15.1nb1 has an empty FILE_SIZE on repository.
warning: package autoconf>=2.62 has an empty FILE_SIZE on repository.
warning: package m4>=1.4 has an empty FILE_SIZE on repository.
warning: package perl>=5.0 has an empty FILE_SIZE on repository.
warning: package libarchive-3.3.3 has an empty FILE_SIZE on repository.
warning: package rsync-3.1.3nb1 has an empty FILE_SIZE on repository.
warning: package osabi-NetBSD-8.99.32 has an empty FILE_SIZE on repository.
warning: package conserver8-8.2.1nb4 has an empty FILE_SIZE on repository.
warning: package py27-curses-2.7.15nb5 has an empty FILE_SIZE on repository.
Memory access violation (core dumped) 

	Here's what I could get from GDB.

Reading symbols from pkgin...(no debugging symbols found)...done.
[New process 1]
Core was generated by `pkgin'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x0000000000697df0 in strlen ()
(gdb) bt
#0  0x0000000000697df0 in strlen ()
#1  0x0000000000687ff2 in strdup ()
#2  0x00000000004092ef in xstrdup ()
#3  0x000000000040547a in order_install ()
#4  0x000000000040388a in pkgin_install ()
#5  0x000000000040435f in pkgin_upgrade ()
#6  0x00000000006b1d85 in main ()
(gdb) file pkgin.debug
warning: exec file is newer than core file.
Reading symbols from pkgin.debug...done.
(gdb) bt
#0  0x0000000000697df0 in strlen ()
#1  0x0000000000687ff2 in _strdup (str=0x0) at /building/work/woods/m-NetBSD-current/lib/libc/string/strdup.c:60
#2  0x0000000000000001 in ?? ()
#3  0x00007c4b5de958f0 in ?? ()
#4  0x0000000000000001 in ?? ()
#5  0x00000000004092ef in xstrdup (str=<optimized out>) at external/xwrapper.c:97
#6  0x0000000000000001 in ?? ()
#7  0x000000000040547a in order_install (impacthead=0x7c4b5de85f98, op=4) at order.c:194
#8  0x0000000000000000 in ?? ()
(gdb) 


(gdb) up
#7  0x000000000040547a in order_install (impacthead=0x7c4b5de85f98, op=4) at order.c:194
194                                     pdp->pkgurl = xstrdup(pimpact->pkgurl);
(gdb) info locals
ordtreehead = 0x7c4b5de85fa8
pimpact = 0x7c4b5de958f0
pdp = <optimized out>
pi_dp = 0x0
i = 1
maxlevel = <optimized out>
tmpcheck = "\220\365A\377\177\177\000\000xenful", '\000' <repeats 250 times>...
(gdb) print pimpact->pkgurl
$2 = 0x0
(gdb) print *pimpact
$3 = {type = 0 '\000', size_pkg = 3165315, old_size_pkg = 3165626, file_size = 0, level = 1, download = 0, pkgurl = 0x0, 
  full = 0x7c4b5de934e0 "autoconf-2.69nb8", name = 0x7c4b5dea4800 "autoconf", old = 0x7c4b5de934c0 "autoconf-2.69nb5", 
  version = 0x0, build_date = 0x7c4b5de934a0 "2019-04-14 13:29:09 -0700", depend = 0x7c4b5dea47f0 "autoconf>=2.62", 
  category = 0x0, pkgpath = 0x0, comment = 0x0, keep = 0, action = 4, next = {sle_next = 0x7c4b5de95860}}


>How-To-Repeat:

>Fix: