(ITS#4311) crash in slapi_op_bind_callback

[dbroady1@yahoo.com]

Full_Name: Darin Broady
Version: 2.3.15 & HEAD
OS: Solaris 9
URL: 
Submission from: (NULL) (192.146.101.24)


In slapi_op_bind_callback (servers/slapd/slapi/slapi_overlay.c), the code in the
default case of the switch statement assumes that op->orb_tmp_mech will be
non-null.  However, I see no place in the code where it is setting that
particular variable.  Hence, when debug is turned on, a null-pointer dereference
occurs with a nice coredump.

The fix would be to do a BER_BVISNULL just like the op->o_conn->c_dn field is
just above it.