CIFS: Make accessing is_valid_oplock/dump_detail ops struct field safe

Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index ccafdedd0dbc..3647b1a4540b 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -1058,13 +1058,15 @@ cifs_demultiplex_thread(void *p)
                 if (mid_entry != NULL) {
                         if (!mid_entry->multiRsp || mid_entry->multiEnd)
                                 mid_entry->callback(mid_entry);
-                } else if (!server->ops->is_oplock_break(buf, server)) {
+                } else if (!server->ops->is_oplock_break ||
+                           !server->ops->is_oplock_break(buf, server)) {
                         cERROR(1, "No task to wake, unknown frame received! "
                                    "NumMids %d", atomic_read(&midCount));
                         cifs_dump_mem("Received Data is: ", buf,
                                       HEADER_SIZE(server));
 #ifdef CONFIG_CIFS_DEBUG2
-                        server->ops->dump_detail(buf);
+                        if (server->ops->dump_detail)
+                                server->ops->dump_detail(buf);
                         cifs_dump_mids(server);
 #endif /* CIFS_DEBUG2 */