Stuck CLOSED sockets / sshd / zombies...

[Karl Pielorz]

Ok, rebuilt a debug world (with your rtld-elf patch), installed it - 
reproduced the issue, and ran up gdb on a 'urdlck' stuck sshd, and got the 
trace below.

Fingers crossed,

-Karl

ps. When running up gdb I get a number of these errors (having checked, 
I've always got these - I just didn't notice before as they scroll past 
right at the top of the output from gdb starting up):

"
Attaching to program: /usr/sbin/sshd, process 2220

warning: current_sos: Can't read pathname for load map: Bad address


warning: current_sos: Can't read pathname for load map: Bad address
"

I'm presuming they can be ignored?

---

"
[Switching to Thread 804006400 (LWP 100083/sshd)]
_umtx_op_err () at /usr/src/lib/libthr/arch/amd64/amd64/_umtx_op_err.S:37
37      RSYSCALL_ERR(_umtx_op)
(gdb) bt
#0  _umtx_op_err () at 
/usr/src/lib/libthr/arch/amd64/amd64/_umtx_op_err.S:37
#1  0x00000008038e304f in __thr_rwlock_rdlock (rwlock=0x803afb480, 
flags=<value optimized out>, tsp=<value optimized out>)
    at /usr/src/lib/libthr/thread/thr_umtx.c:277
#2  0x00000008038ea22c in _thr_rtld_rlock_acquire (lock=0x803afb480) at 
thr_umtx.h:196
#3  0x000000080064f9a2 in rlock_acquire (lock=0x80085fe00, 
lockstate=0x7fffffffc058) at /usr/src/libexec/rtld-elf/rtld_lock.c:197
#4  0x00000008006498c9 in _rtld_bind (obj=0x800662000, reloff=13008) at 
/usr/src/libexec/rtld-elf/rtld.c:675
#5  0x00000008006470cd in _rtld_bind_start () at 
/usr/src/libexec/rtld-elf/amd64/rtld_start.S:121
#6  0x000000000041072c in grace_alarm_handler (sig=0) at 
/usr/src/secure/usr.sbin/sshd/../../../crypto/openssh/sshd.c:378
#7  <signal handler called>
#8  _umtx_op_err () at 
/usr/src/lib/libthr/arch/amd64/amd64/_umtx_op_err.S:37
#9  0x00000008038e304f in __thr_rwlock_rdlock (rwlock=0x803afb480, 
flags=<value optimized out>, tsp=<value optimized out>)
    at /usr/src/lib/libthr/thread/thr_umtx.c:277
#10 0x00000008038ea22c in _thr_rtld_rlock_acquire (lock=0x803afb480) at 
thr_umtx.h:196
#11 0x000000080064f9a2 in rlock_acquire (lock=0x80085fe00, 
lockstate=0x7fffffffc668) at /usr/src/libexec/rtld-elf/rtld_lock.c:197
#12 0x00000008006498c9 in _rtld_bind (obj=0x800662000, reloff=9240) at 
/usr/src/libexec/rtld-elf/rtld.c:675
#13 0x00000008006470cd in _rtld_bind_start () at 
/usr/src/libexec/rtld-elf/amd64/rtld_start.S:121
#14 0x000000000042f9dd in sshpam_sigchld_handler (sig=<value optimized 
out>) at 
/usr/src/secure/usr.sbin/sshd/../../../crypto/openssh/auth-pam.c:152
#15 <signal handler called>
#16 0x000000080064a1c4 in dlclose (handle=0x800696c00) at 
/usr/src/libexec/rtld-elf/rtld.c:4136
#17 0x0000000800ede121 in openpam_destroy_chain (chain=0x8040634e0)
    at 
/usr/src/lib/libpam/libpam/../../../contrib/openpam/lib/libpam/openpam_load.c:92
#18 0x0000000800ede0bc in openpam_destroy_chain (chain=0x804063460)
    at 
/usr/src/lib/libpam/libpam/../../../contrib/openpam/lib/libpam/openpam_load.c:109
#19 0x0000000800ede0bc in openpam_destroy_chain (chain=0x8040633e0)
    at 
/usr/src/lib/libpam/libpam/../../../contrib/openpam/lib/libpam/openpam_load.c:109
#20 0x0000000800ede051 in openpam_clear_chains (policy=0x80401a6c8)
    at 
/usr/src/lib/libpam/libpam/../../../contrib/openpam/lib/libpam/openpam_load.c:128
#21 0x0000000800eda9e7 in pam_end (pamh=0x80401a6c0, status=<value 
optimized out>)
    at 
/usr/src/lib/libpam/libpam/../../../contrib/openpam/lib/libpam/pam_end.c:83
#22 0x000000000042e15d in sshpam_cleanup () at 
/usr/src/secure/usr.sbin/sshd/../../../crypto/openssh/auth-pam.c:614
#23 0x000000000041d58f in do_cleanup (authctxt=0x80401a600) at 
/usr/src/secure/usr.sbin/sshd/../../../crypto/openssh/session.c:2732
#24 0x000000000041064f in ssh_cleanup_exit (i=255) at 
/usr/src/secure/usr.sbin/sshd/../../../crypto/openssh/sshd.c:2545
#25 0x0000000000428f83 in mm_request_receive (sock=<value optimized out>, 
m=<value optimized out>)
    at 
/usr/src/secure/usr.sbin/sshd/../../../crypto/openssh/monitor_wrap.c:153
#26 0x0000000000427e26 in monitor_read (pmonitor=0x804022220, ent=0x6465a0, 
pent=0x7fffffffd240)
    at /usr/src/secure/usr.sbin/sshd/../../../crypto/openssh/monitor.c:593
#27 0x0000000000427b49 in monitor_child_preauth (_authctxt=<value optimized 
out>, pmonitor=0x804022220)
    at /usr/src/secure/usr.sbin/sshd/../../../crypto/openssh/monitor.c:387
#28 0x000000000040fd15 in main (ac=<value optimized out>, av=<value 
optimized out>)
    at /usr/src/secure/usr.sbin/sshd/../../../crypto/openssh/sshd.c:679
"