Samba4 panic action

[Jeremy Allison]

On Fri, Oct 12, 2012 at 04:22:39PM +0200, steve wrote:
> On 12/10/12 14:21, Ricky Nance wrote:
> >Steve, if you are building from git, the file gdb_backtrace can be found
> >at samba-master/selftest/gdb_backtrace, you will just simply add the
> >line to your smb.conf pointing at that file, and restart samba, then try
> >to recreate the bug. You should then get backtraces in
> >/usr/local/samba/var as files.
> >
> >Ricky
> 
> Hi Ricky.
> Thanks. Much easier.
> Cheers,
> Steve
> 
> Here is the trace:
> 
> /usr/local/samba/sbin/smbd: smb_panic(): calling panic action
> [/home/steve/samba-master/selftest/gdb_backtrace 2716]
> Kerberos: TGS-REQ authtime: 2012-10-12T16:13:58 starttime:
> 2012-10-12T16:14:51 endtime: 2012-10-13T02:13:58 renew till:
> 2012-10-19T16:13:58
> Tkey handshake completed
> Terminating connection - 'dns_tcp_call_loop:
> tstream_read_pdu_blob_recv() - NT_STATUS_CONNECTION_DISCONNECTED'
> single_terminate: reason[dns_tcp_call_loop:
> tstream_read_pdu_blob_recv() - NT_STATUS_CONNECTION_DISCONNECTED]
> /usr/local/samba/sbin/smbd: [Thread debugging using libthread_db enabled]
> /usr/local/samba/sbin/smbd: Using host libthread_db library
> "/lib/libthread_db.so.1".
> /usr/local/samba/sbin/smbd: 0xb775b424 in __kernel_vsyscall ()
> /usr/local/samba/sbin/smbd: #0  0xb775b424 in __kernel_vsyscall ()
> /usr/local/samba/sbin/smbd: No symbol table info available.
> /usr/local/samba/sbin/smbd: #1  0xb6a78523 in __waitpid_nocancel ()
> from /lib/libc.so.6
> /usr/local/samba/sbin/smbd: No symbol table info available.
> /usr/local/samba/sbin/smbd: #2  0xb6a015c0 in do_system () from
> /lib/libc.so.6
> /usr/local/samba/sbin/smbd: No symbol table info available.
> /usr/local/samba/sbin/smbd: #3  0xb772eecb in system () from
> /lib/libpthread.so.0
> /usr/local/samba/sbin/smbd: No symbol table info available.
> /usr/local/samba/sbin/smbd: #4  0xb710d65b in smb_panic_s3
> (why=0xb7712881 "internal error") at ../source3/lib/util.c:823
> /usr/local/samba/sbin/smbd:         cmd = 0x99f38f0
> "/home/steve/samba-master/selftest/gdb_backtrace 2716"
> /usr/local/samba/sbin/smbd:         result = -1081235480
> /usr/local/samba/sbin/smbd:         __FUNCTION__ = "smb_panic_s3"
> /usr/local/samba/sbin/smbd: #5  0xb7700ea2 in smb_panic
> (why=0xb7712881 "internal error") at ../lib/util/fault.c:159
> /usr/local/samba/sbin/smbd: No locals.
> /usr/local/samba/sbin/smbd: #6  0xb7700b63 in fault_report (sig=11)
> at ../lib/util/fault.c:77
> /usr/local/samba/sbin/smbd:         counter = 1
> /usr/local/samba/sbin/smbd:         __FUNCTION__ = "fault_report"
> /usr/local/samba/sbin/smbd: #7  0xb7700b74 in sig_fault (sig=11) at
> ../lib/util/fault.c:88
> /usr/local/samba/sbin/smbd: No locals.
> /usr/local/samba/sbin/smbd: #8  <signal handler called>
> /usr/local/samba/sbin/smbd: No symbol table info available.
> /usr/local/samba/sbin/smbd: #9  0xb695556a in security_token_has_sid
> (token=0x0, sid=0x99f3790) at
> ../libcli/security/security_token.c:109
> /usr/local/samba/sbin/smbd:         i = 0
> /usr/local/samba/sbin/smbd: #10 0xb6955bb4 in se_access_check
> (sd=0x99f35d0, token=0x0, access_desired=1,
> access_granted=0xbf8dae78) at ../libcli/security/access_check.c:229

Very interesting backtrace. We have the pointer token=0x0, which I should not
be possible. Luckily this is in master so won't break 4.0.0rc's

Jeremy.