pwauth segfault when it uses pam_smbpass and pam_winbind modules

[GoogleCodeExporter]

What steps will reproduce the problem?
1./etc/nsswitch.conf
passwd:     files winbind
shadow:     files winbind
group:      files winbind

2. /etc/pam.d/pwauth
#%PAM-1.0
auth       sufficient   /lib/security/pam_winbind.so 
account    required     /lib/security/pam_nologin.so
account    sufficient   /lib/security/pam_winbind.so
password   sufficient   /lib/security/pam_smbpass.so
password   required     /lib/security/pam_winbind.so
session    required pam_mkhomedir.so
session    required pam_winbind.so
session    required     /lib/security/pam_unix.so

3. /usb/sbin/pwauth

4. Type samba users or AD domain users credentials

What is the expected output? What do you see instead?
Although it should validate the credential, it core dumps instead.
/etc/var/log/apache_error_log
[Thu Aug 15 11:02:47.867264 2013] [authnz_external:error] [pid 8374] [client 
10.39.17.36:49897] External authenticator died on signal 11
[Thu Aug 15 11:02:47.867329 2013] [authnz_external:error] [pid 8374] [client 
10.39.17.36:49897] AuthExtern pwauth [/usr/sbin/pwauth]: Failed (-2) for user 
admin
[Thu Aug 15 11:02:47.867338 2013] [auth_basic:error] [pid 8374] [client 
10.39.17.36:49897] AH01617: user admin: authentication failure for 
"/webdav/Backups": Password Mismatch

/var/log/messages
Aug 15 10:49:15 vmstore kernel: [ 1361.635185] pwauth[9079]: segfault at 
b75b3eb7 ip b75b3eb7 sp bfb6675c error 4 in libpthread-2.13.so[b75c8000+15000]
Aug 15 10:49:18 vmstore kernel: [ 1364.566193] pwauth[9093]: segfault at 
b7561eb7 ip b7561eb7 sp bfd4ae2c error 4 in libpthread-2.13.so[b7576000+15000]
Aug 15 11:02:47 vmstore kernel: [ 2171.892085] pwauth[10695]: segfault at 
b75b2eb7 ip b75b2eb7 sp bfb96d7c error 4 in libpthread-2.13.so[b75c7000+15000]

What version of the product are you using? On what operating system?
pwauth-2.3.8 (which comes with Debian Wheezy)

Please provide any additional information below.

It seems the problem arises when it finishes the job with one pam module 
(pam_smbpass/pam_winbind) and tries to go to the next. Maybe pwauth corrupted 
pam somehow !

no talloc stackframe at ../source3/param/loadparm.c:4842, leaking memory

Program received signal SIGSEGV, Segmentation fault.
0xb7e21eb7 in ?? ()
(gdb) bt
#0  0xb7e21eb7 in ?? ()
#1  0xb7ba16e1 in _talloc_free_internal (ptr=0x8061a90, location=0xb7ba44c7 
"../lib/talloc/talloc.c:2251") at ../lib/talloc/talloc.c:831
#2  0xb7ba23f0 in _talloc_free_children_internal (tc=0x804c0a8, ptr=0x804c0d8, 
location=0xb7ba44c7 "../lib/talloc/talloc.c:2251") at 
../lib/talloc/talloc.c:1256
#3  0xb7ba1830 in _talloc_free_internal (ptr=0x804c0d8, location=0xb7ba44c7 
"../lib/talloc/talloc.c:2251") at ../lib/talloc/talloc.c:851
#4  0xb7ba2742 in _talloc_free (ptr=0x804c0d8, location=0xb7ba44c7 
"../lib/talloc/talloc.c:2251") at ../lib/talloc/talloc.c:1371
#5  0xb7ba3d82 in talloc_autofree () at ../lib/talloc/talloc.c:2251
#6  0xb7ea05e8 in __cxa_finalize () from /lib/i386-linux-gnu/libc.so.6
#7  0xb7ba0a43 in __do_global_dtors_aux () from 
/usr/local/samba/lib/private/libtalloc.so.2
#8  0xb7ff4e52 in ?? () from /lib/ld-linux.so.2
#9  0xb7ff5947 in ?? () from /lib/ld-linux.so.2
#10 0xb7e6ccc4 in ?? () from /lib/i386-linux-gnu/libdl.so.2
#11 0xb7fefde6 in ?? () from /lib/ld-linux.so.2
#12 0xb7e6d0bc in ?? () from /lib/i386-linux-gnu/libdl.so.2
#13 0xb7e6ccfa in dlclose () from /lib/i386-linux-gnu/libdl.so.2
#14 0xb7fc6f8b in ?? () from /lib/i386-linux-gnu/libpam.so.0
#15 0xb7fc48ff in ?? () from /lib/i386-linux-gnu/libpam.so.0
#16 0xb7fc1da0 in pam_end () from /lib/i386-linux-gnu/libpam.so.0
#17 0x08048bff in check_auth (login=0xbffff4aa "admin", passwd=0xbffff8ab 
"soho") at auth_pam.c:186
#18 0x0804898e in main (argc=1, argv=0xbffffd64) at main.c:94

Original issue reported on code.google.com by [email protected] on 15 Aug 2013 at 6:06