pkg/43603: pkgsrc xdm-1.19nb1 crashes on wrong password

[ignatios%cs.uni-bonn.de@localhost]

>Number:         43603
>Category:       pkg
>Synopsis:       pkgsrc xdm-1.19nb1 crashes on wrong password
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Jul 12 10:00:00 +0000 2010
>Originator:     ignatios%cs.uni-bonn.de@localhost
>Release:        NetBSD 5.1_RC3
>Organization:
computer science department, university of Bonn, Germany
>Environment:
System: NetBSD kolmogorov 5.1_RC3 NetBSD 5.1_RC3 (GENERIC) #0: Tue Jul 6 
13:10:21 CEST 2010 
ignatios@random87:/var/itch/obj/5i386/sys/arch/i386/compile/GENERIC i386
Architecture: i386
Machine: i386
>Description:
        typing in the wrong username/password combination at xdm 1.19nb1
(from pkgsrc-2010Q1) results in a crashed xdm.

Stack backtrace is:


Loaded symbols for /usr/libexec/ld.elf_so
Core was generated by `xdm'.
Program terminated with signal 11, Segmentation fault.
#0  0xbb9d1bcf in __vfprintf_unlocked () from /usr/lib/libc.so.12
(gdb) where
#0  0xbb9d1bcf in __vfprintf_unlocked () from /usr/lib/libc.so.12
#1  0xbb94f9a6 in vsnprintf () from /usr/lib/libc.so.12
#2  0xbb9d6e96 in vsyslog_r () from /usr/lib/libc.so.12
#3  0xbb9d7194 in vsyslog () from /usr/lib/libc.so.12
#4  0xbb9d71c1 in syslog () from /usr/lib/libc.so.12
#5  0xbb920bdd in GreetUser () from /usr/pkg/lib/X11/xdm/libXdmGreet.so
#6  0x080524b6 in ManageSession ()
#7  0x0804f270 in StartDisplay ()
#8  0x0804e808 in ForEachDisplay ()
#9  0x0804f444 in StartDisplay ()
#10 0x0804fe1d in WaitForChild ()
#11 0x08053cb1 in WaitForSomething ()
#12 0x0804f75d in main ()
(gdb) Quit
(gdb) #

Minor nit, but possibly related: xdm misrepresents the signal received
from the child process. Note that 2816 is 11*256. From xdm.log:

xdm error (pid 13603): pam_authenticate failure: unknown user
xdm error (pid 8724): Unknown session exit code 2816 from process 13603
X connection to :0.0 broken (explicit kill or server shutdown).
disable FP1
disable primary dac
finished PLL2
finished PLL1
Entering Restore TV
Restore TV PLL
Restore TVHV
Restore TV Restarts
Restore Timing Tables
Restore TV standard
Leaving Restore TV
xdm info (pid 8724): Exiting


>How-To-Repeat:
        [username:] foo
        [password:] bar
>Fix:
        Workaround: revert to xdm 1.1.6nb2 (pkgsrc-2009Q4)

>Unformatted:
        But I've got the same report from 5.0.2; stack traceback is the same.