cifs: only set ops for inodes in I_NEW state

It's generally not safe to reset the inode ops once they've been set. In
the case where the inode was originally thought to be a directory and
then later found to be a DFS referral, this can lead to an oops when we
try to trigger an inode op on it after changing the ops to the blank
referral operations.

Cc: <stable@vger.kernel.org>
Reported-and-Tested-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
tracing: Return -EBUSY when event_enable_func() fails to get module

Since try_module_get() returns false( = 0) when it fails to
pindown a module, event_enable_func() returns 0 which means
"succeed". This can cause a kernel panic when the entry
is removed, because the event is already released.

This fixes the bug by returning -EBUSY, because the reason
why it fails is that the module is being removed at that time.

Link: http://lkml.kernel.org/r/20130516114848.13508.97899.stgit@mhiramat-M0-7522

Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tom Zanussi <tom.zanussi@intel.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6

Pull CIFS fix from Steve French:
 "One cifs fix to merge now - fixes possible DFS oops (I expect to
  request a merge of 4 additional cifs fixes next week)"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: only set ops for inodes in I_NEW state
Merge tag 'trace-fixes-v3.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "Masami Hiramatsu fixed another bug.  This time returning a proper
  result in event_enable_func().  After checking the return status of
  try_module_get(), it returned the status of try_module_get().

  But try_module_get() returns 0 on failure, which is success for
  event_enable_func()"

* tag 'trace-fixes-v3.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Return -EBUSY when event_enable_func() fails to get module