smb3: Do not send SMB3 SET_INFO if nothing changed

An earlier commit had a typo which prevented the
optimization from working:

commit 18dd8e1a65dd ("Do not send SMB3 SET_INFO request if nothing is changing")

Thank you to Metze for noticing this.  Also clear a
reserved field in the FILE_BASIC_INFO struct we send
that should be zero (all the other fields in that
struct were set or cleared explicitly already in
cifs_set_file_info).

Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org> # 4.9.x+
Reported-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 054e880c1dac..d32eaa4b2437 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -1120,6 +1120,8 @@ cifs_set_file_info(struct inode *inode, struct iattr *attrs, unsigned int xid,
         if (!server->ops->set_file_info)
                 return -ENOSYS;
 
+        info_buf.Pad = 0;
+
         if (attrs->ia_valid & ATTR_ATIME) {
                 set_time = true;
                 info_buf.LastAccessTime =