smbd segfaults at least twice a day

[Edson Manners]

The Samba 'panic action' script, /usr/share/samba/panic-action,
was called for PID 4493 (/usr/sbin/smbd).

This means there was a problem with the program, such as a segfault.
Below is a backtrace for this process generated with gdb, which shows
the state of the program at the time the error occurred. The Samba log
files may contain additional information about the problem.

If the problem persists, you are encouraged to first install the
samba-dbg package, which contains the debugging symbols for the Samba
binaries. Then submit the provided information as a bug report to
Ubuntu by visiting this link:
https://launchpad.net/ubuntu/+source/samba/+filebug

[Thread debugging using libthread_db enabled]
0x00007fb0a3ecedee in waitpid () from /lib/libc.so.6
#0 0x00007fb0a3ecedee in waitpid () from /lib/libc.so.6
#1 0x00007fb0a3e66a79 in ?? () from /lib/libc.so.6
#2 0x00007fb0a6da39b4 in smb_panic (why=<value optimized out>) at lib/util.c:1471
#3 0x00007fb0a6d9328d in fault_report (sig=11) at lib/fault.c:52
#4 sig_fault (sig=11) at lib/fault.c:75
#5 <signal handler called>
#6 0x00007fb0a3ea7e52 in ?? () from /lib/libc.so.6
#7 0x00007fb0a6d7981e in rep_strlcpy (d=0x7fffe1373d28 "", s=0x0, bufsize=256) at ../lib/replace/replace.c:69
#8 0x00007fb0a6db0494 in connections_fetch_entry (mem_ctx=0x0, conn=0x7fb0a8dd9770, name=0x0) at lib/conn_tdb.c:65
#9 0x00007fb0a6b2d666 in yield_connection (conn=0x7fb0a8dd9770, name=0x0) at smbd/connection.c:33
#10 0x00007fb0a6b9b496 in close_cnum (conn=0x7fb0a8dd9770, vuid=100) at smbd/service.c:1256
#11 0x00007fb0a6b34d1c in conn_close_all (sconn=<value optimized out>) at smbd/conn.c:185
#12 0x00007fb0a709ed25 in exit_server_common (how=SERVER_EXIT_NORMAL, reason=0x7fb0a70c9047 "failed to receive smb request") at smbd/server.c:852
#13 0x00007fb0a709ef4e in exit_server_cleanly (explanation=0x0) at smbd/server.c:931
#14 0x00007fb0a6b9a8ab in smbd_server_connection_read_handler (ev=<value optimized out>, fde=<value optimized out>, flags=<value optimized out>, private_data=<value optimized out>) at smbd/process.c:2115
#15 smbd_server_connection_handler (ev=<value optimized out>, fde=<value optimized out>, flags=<value optimized out>, private_data=<value optimized out>) at smbd/process.c:2137
#16 0x00007fb0a6db3422 in run_events (ev=0x7fb0a8d21430, selrtn=1, read_fds=0x7fffe1374120, write_fds=0x7fffe13740a0) at lib/events.c:156
#17 0x00007fb0a6b995f0 in smbd_server_connection_loop_once () at smbd/process.c:840
#18 smbd_process () at smbd/process.c:2451
#19 0x00007fb0a709f1ee in smbd_accept_connection (ev=<value optimized out>, fde=<value optimized out>, flags=<value optimized out>, private_data=<value optimized out>) at smbd/server.c:438
#20 0x00007fb0a6db3422 in run_events (ev=0x7fb0a8d21430, selrtn=1, read_fds=0x7fffe1374430, write_fds=0x7fffe13743b0) at lib/events.c:156
#21 0x00007fb0a6db36e1 in s3_event_loop_once (ev=0x7fb0a8d21430, location=<value optimized out>) at lib/events.c:219
#22 0x00007fb0a6db3ac0 in _tevent_loop_once (ev=0x7fb0a8d21430, location=0x7fb0a72a5658 "smbd/server.c:726") at ../lib/tevent/tevent.c:497
#23 0x00007fb0a709fed3 in smbd_parent_loop (argc=<value optimized out>, argv=0x7fffe13747b0) at smbd/server.c:726
#24 main (argc=<value optimized out>, argv=0x7fffe13747b0) at smbd/server.c:1316
A debugging session is active.

 Inferior 1 [process 4493] will be detached.

Quit anyway? (y or n) [answered Y; input not from terminal]

------------------------------------------------------------------------------------------------------------
:~$ lsb_release -rd
Description: Ubuntu 10.10
Release: 10.10

:~$ apt-cache policy samba
samba:
  Installed: 2:3.5.4~dfsg-1ubuntu8.4
  Candidate: 2:3.5.4~dfsg-1ubuntu8.4
  Version table:
 *** 2:3.5.4~dfsg-1ubuntu8.4 0
        500 http://us.archive.ubuntu.com/ubuntu/ maverick-updates/main amd64 Packages
        100 /var/lib/dpkg/status
     2:3.5.4~dfsg-1ubuntu8.3 0
        500 http://security.ubuntu.com/ubuntu/ maverick-security/main amd64 Packages
     2:3.5.4~dfsg-1ubuntu8 0
        500 http://us.archive.ubuntu.com/ubuntu/ maverick/main amd64 Packages

[Ofer Chen (oferchen)]

I got the same error when clients are accessing the samba server at random occurrences it happens few times a day

lsb_release -rd
Description: Ubuntu 11.04
Release: 11.04

uname -a
Linux 2.6.38-10-generic #46-Ubuntu SMP Tue Jun 28 15:07:17 UTC 2011 x86_64 GNU/Linux

apt-cache policy samba
samba:
  Installed: 2:3.5.8~dfsg-1ubuntu2.2
  Candidate: 2:3.5.8~dfsg-1ubuntu2.2
  Version table:
 *** 2:3.5.8~dfsg-1ubuntu2.2 0
        500 http://archive.ubuntu.com/ubuntu/ natty-updates/main amd64 Packages
        100 /var/lib/dpkg/status
     2:3.5.8~dfsg-1ubuntu2 0
        500 http://archive.ubuntu.com/ubuntu/ natty/main amd64 Packages

Thread debugging using libthread_db enabled]
0x00007f9b6bb191ae in waitpid () from /lib/x86_64-linux-gnu/libc.so.6
#0 0x00007f9b6bb191ae in waitpid () from /lib/x86_64-linux-gnu/libc.so.6
#1 0x00007f9b6baadd6e in ?? () from /lib/x86_64-linux-gnu/libc.so.6
#2 0x00007f9b6e9fec53 in smb_panic (why=<value optimized out>) at lib/util.c:1471
#3 0x00007f9b6e9ee2e9 in fault_report (sig=11) at lib/fault.c:52
#4 sig_fault (sig=11) at lib/fault.c:75
#5 <signal handler called>
#6 0x00007f9b6baee5d1 in ?? () from /lib/x86_64-linux-gnu/libc.so.6
#7 0x00007f9b6e9d511e in rep_strlcpy (d=0x7fff13d66918 "", s=0x0, bufsize=256) at ../lib/replace/replace.c:69
#8 0x00007f9b6ea0b434 in connections_fetch_entry (mem_ctx=0x0, conn=0x7f9b7094c920, name=0x0) at lib/conn_tdb.c:65
#9 0x00007f9b6e78c676 in yield_connection (conn=0x7f9b7094c920, name=0x0) at smbd/connection.c:33
#10 0x00007f9b6e7fd7f6 in close_cnum (conn=0x7f9b7094c920, vuid=101) at smbd/service.c:1256
#11 0x00007f9b6e7b916d in reply_tdis (req=0x7f9b70955b00) at smbd/reply.c:4912
#12 0x00007f9b6e7f8bb5 in switch_message (type=113 'q', req=0x7f9b70955b00, size=39) at smbd/process.c:1404
#13 0x00007f9b6e7f8f57 in construct_reply (inbuf=<value optimized out>, nread=39, unread_bytes=0, seqnum=0, encrypted=false, deferred_pcd=0x0, conn=<value optimized out>) at smbd/process.c:1436
#14 process_smb (inbuf=<value optimized out>, nread=39, unread_bytes=0, seqnum=0, encrypted=false, deferred_pcd=0x0, conn=<value optimized out>) at smbd/process.c:1509
#15 0x00007f9b6e7f93da in smbd_server_connection_read_handler (ev=<value optimized out>, fde=<value optimized out>, flags=<value optimized out>, private_data=<value optimized out>) at smbd/process.c:2126
#16 smbd_server_connection_handler (ev=<value optimized out>, fde=<value optimized out>, flags=<value optimized out>, private_data=<value optimized out>) at smbd/process.c:2141
#17 0x00007f9b6ea0e303 in run_events (ev=0x7f9b7086d430, selrtn=1, read_fds=0x7fff13d66d90, write_fds=0x7fff13d66d10) at lib/events.c:157
#18 0x00007f9b6e7fa936 in smbd_server_connection_loop_once () at smbd/process.c:844
#19 smbd_process () at smbd/process.c:2455
#20 0x00007f9b6ecf991e in smbd_accept_connection (ev=<value optimized out>, fde=<value optimized out>, flags=<value optimized out>, private_data=<value optimized out>) at smbd/server.c:438
#21 0x00007f9b6ea0e303 in run_events (ev=0x7f9b7086d430, selrtn=1, read_fds=0x7fff13d670b0, write_fds=0x7fff13d67030) at lib/events.c:157
#22 0x00007f9b6ea0e4f8 in s3_event_loop_once (ev=0x7f9b7086d430, location=<valu...

[niallm90 (niallm90)]

I all so appear to be getting this error. I have enabled 'debug level = 3' in my smb.conf so am waiting for another error to get some more information. It happens a random amount of times a day. It appears to happen when you connect to a share or try to open a file on the share. I have only experienced the problem on Windows 7 client but I don't access the share often from Ubuntu clients.

smb.conf - (with out comments)
-----------------------------------------------------------------------------------
[global]
   workgroup = WORKGROUP
   server string = %h server (Samba, Ubuntu)
   dns proxy = no
follow symlinks=yes
unix extensions = no
   debug level = 3
   log file = /var/log/samba/log.%m
   max log size = 1000
   syslog = 0
   panic action = /usr/share/samba/panic-action %d
   encrypt passwords = true
   passdb backend = tdbsam
   obey pam restrictions = yes
   unix password sync = yes
   passwd program = /usr/bin/passwd %u
   passwd chat = *Enter\snew\s*\spassword:* %n\n *Retype\snew\s*\spassword:* %n\n *password\supdated\ssuccessfully* .
   pam password change = yes
   map to guest = bad user
   usershare allow guests = yes
-----------------------------------------------------------------------------------

lsb_release -rd
-----------------------------------------------------------------------------------
Description: Ubuntu 11.04
Release: 11.04
-----------------------------------------------------------------------------------

uname -a
-----------------------------------------------------------------------------------
Linux niall-desktop 2.6.38-11-generic #48-Ubuntu SMP Fri Jul 29 19:02:55 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux
-----------------------------------------------------------------------------------

apt-cache policy samba
-----------------------------------------------------------------------------------
samba:
  Installed: 2:3.5.8~dfsg-1ubuntu2.3
  Candidate: 2:3.5.8~dfsg-1ubuntu2.3
  Version table:
 *** 2:3.5.8~dfsg-1ubuntu2.3 0
        500 http://ucmirror.canterbury.ac.nz/ubuntu/ natty-security/main amd64 Packages
        100 /var/lib/dpkg/status
     2:3.5.8~dfsg-1ubuntu2 0
        500 http://ucmirror.canterbury.ac.nz/ubuntu/ natty/main amd64 Packages
-----------------------------------------------------------------------------------

-----------------------------------------------------------------------------------
[Thread debugging using libthread_db enabled]
0x00007fd99f6b01ae in waitpid () from /lib/x86_64-linux-gnu/libc.so.6
#0 0x00007fd99f6b01ae in waitpid () from /lib/x86_64-linux-gnu/libc.so.6
#1 0x00007fd99f644d6e in ?? () from /lib/x86_64-linux-gnu/libc.so.6
#2 0x00007fd9a2595c53 in smb_panic (why=<value optimized out>) at lib/util.c:1471
#3 0x00007fd9a25852e9 in fault_report (sig=11) at lib/fault.c:52
#4 sig_fault (sig=11) at lib/fault.c:75
#5 <signal handler called>
#6 0x00007fd99f6855d1 in ?? () from /lib/x86_64-linux-gnu/libc.so.6
#7 0x00007fd9a256c11e in rep_strlcpy (d=0x7fff506b6ff8 "", s=0x0, bufsize=256) at ../lib/replace/replace.c:69
#8 0x00007fd9a25a2434 in connections_fetch_entry (mem_ctx=0x0, conn=0x7fd9a3657150, name=0x0) at lib/conn_tdb.c:65
#9 0x00007fd9a2323676 in yield_connection...

[lazikas (lazikas)]

It also happens t me 2-3 times per day. Server is getting up (automatically ?) again. This is the mail i get:
----------------------------------------------------------------
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
0x00007fe2754ec44e in waitpid () from /lib/x86_64-linux-gnu/libc.so.6
#0 0x00007fe2754ec44e in waitpid () from /lib/x86_64-linux-gnu/libc.so.6
#1 0x00007fe27547229e in ?? () from /lib/x86_64-linux-gnu/libc.so.6
#2 0x00007fe2788c2c5c in smb_panic (why=<optimized out>) at lib/util.c:1123
#3 0x00007fe2788b3ef8 in fault_report (sig=11) at lib/fault.c:53
#4 sig_fault (sig=11) at lib/fault.c:76
#5 <signal handler called>
#6 0x00007fe2754b6111 in ?? () from /lib/x86_64-linux-gnu/libc.so.6
#7 0x00007fe278898c7e in rep_strlcpy (d=0x7ffff3cdb2f4 "", s=0x0, bufsize=256) at ../lib/replace/replace.c:70
#8 0x00007fe2788cf4d4 in connections_fetch_entry (mem_ctx=0x7fe27a0c0480, conn=0x7fe27a0c3300, name=0x0) at lib/conn_tdb.c:63
#9 0x00007fe2785b110c in yield_connection (conn=0x7fe27a0c3300, name=0x0) at smbd/connection.c:37
#10 0x00007fe278625ff3 in close_cnum (conn=0x7fe27a0c3300, vuid=100) at smbd/service.c:1350
#11 0x00007fe2785df31d in reply_tdis (req=0x7fe27a0c0560) at smbd/reply.c:5105
#12 0x00007fe278620fd4 in switch_message (type=113 'q', req=0x7fe27a0c0560, size=39) at smbd/process.c:1574
#13 0x00007fe2786213eb in construct_reply (deferred_pcd=0x0, encrypted=false, seqnum=<optimized out>, unread_bytes=0, size=39, inbuf=0x0, sconn=0x7fe27a07d5e0) at smbd/process.c:1610
#14 process_smb (sconn=0x7fe27a07d5e0, inbuf=<optimized out>, nread=39, unread_bytes=0, seqnum=<optimized out>, encrypted=false, deferred_pcd=0x0) at smbd/process.c:1688
#15 0x00007fe278621803 in smbd_server_connection_read_handler (conn=0x7fe27a07d5e0, fd=8) at smbd/process.c:2317
#16 0x00007fe2788d291e in run_events_poll (num_pfds=2, pfds=0x7fe27a086aa0, pollrtn=<optimized out>, ev=0x7fe27a07d520) at lib/events.c:286
#17 run_events_poll (ev=0x7fe27a07d520, pollrtn=<optimized out>, pfds=0x7fe27a086aa0, num_pfds=2) at lib/events.c:184
#18 0x00007fe278622f72 in smbd_server_connection_loop_once (conn=0x7fe27a07d5e0) at smbd/process.c:1017
#19 smbd_process (sconn=0x7fe27a07d5e0) at smbd/process.c:3158
#20 0x00007fe278b3078f in smbd_accept_connection (ev=<optimized out>, fde=<optimized out>, flags=<optimized out>, private_data=<optimized out>) at smbd/server.c:511
#21 0x00007fe2788d291e in run_events_poll (num_pfds=5, pfds=0x7fe27a095370, pollrtn=<optimized out>, ev=0x7fe27a07d520) at lib/events.c:286
#22 run_events_poll (ev=0x7fe27a07d520, pollrtn=<optimized out>, pfds=0x7fe27a095370, num_pfds=5) at lib/events.c:184
#23 0x00007fe2788d2aba in s3_event_loop_once (ev=0x7fe27a07d520, location=<optimized out>) at lib/events.c:349
#24 0x00007fe2788d3640 in _tevent_loop_once (ev=0x7fe27a07d520, location=0x7fe278d35497 "smbd/server.c:844") at ../lib/tevent/tevent.c:494
#25 0x00007fe2785a1060 in smbd_parent_loop (parent=<optimized out>) at smbd/server.c:844
#26 main (argc=<optimized out>, argv=<optimized out>) at smbd/server.c:1326
A debugging session is active.

 Inferior 1 [process 16167] wil...