[bug report] dcbnl: Shorten all command handling functions

[bug report] dcbnl: Shorten all command handling functions

[Dan Carpenter]

The patch 7be994138b18: "dcbnl: Shorten all command handling
functions" from Jun 13, 2012, leads to the following static checker
warning:

	net/dcb/dcbnl.c:1509 dcbnl_ieee_set()
	warn: passing signed to unsigned: 'err'

net/dcb/dcbnl.c
  1491                                  continue;
  1492  
  1493                          if (nla_len(attr) < sizeof(struct dcb_app)) {
  1494                                  err = -ERANGE;
  1495                                  goto err;
  1496                          }
  1497  
  1498                          app_data = nla_data(attr);
  1499                          if (ops->ieee_setapp)
  1500                                  err = ops->ieee_setapp(netdev, app_data);
  1501                          else
  1502                                  err = dcb_ieee_setapp(netdev, app_data);
  1503                          if (err)
  1504                                  goto err;

"err" is negative error codes.

  1505                  }
  1506          }
  1507  
  1508  err:
  1509          err = nla_put_u8(skb, DCB_ATTR_IEEE, err);
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
It's not clear what this is doing but it truncates "err" to a u8 and
sets err to zero.

  1510          dcbnl_ieee_notify(netdev, RTM_SETDCB, DCB_CMD_IEEE_SET, seq, 0);
  1511          return err;
  1512  }

There is a similar one at the end of dcbnl_ieee_del() as well.  I've no
idea how to fix this.

regards,
dan carpenter

Re: [bug report] dcbnl: Shorten all command handling functions

[David Miller]

From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Tue, 25 Feb 2020 10:14:08 +0300

> The patch 7be994138b18: "dcbnl: Shorten all command handling
> functions" from Jun 13, 2012, leads to the following static checker
> warning:
> 
> 	net/dcb/dcbnl.c:1509 dcbnl_ieee_set()
> 	warn: passing signed to unsigned: 'err'

The problem exists before this commit, it's just that the u8 truncated
'err' is passed into dcbnl_reply().

Yeah this is quite a mess.