qeth: BRIDGEPORT "sanity check"

Forbid enabling IFF_PROMISC reflection to BRIDGEPORT when a role
is already assigned, and forbid direct manipulation of the role
when reflection mode is engaged.

Reviewed-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Signed-off-by: Eugene Crosser <Eugene.Crosser@ru.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/s390/net/qeth_l2_sys.c b/drivers/s390/net/qeth_l2_sys.c
index a553fba..52673cd 100644 (file)
--- a/drivers/s390/net/qeth_l2_sys.c
+++ b/drivers/s390/net/qeth_l2_sys.c
@@ -86,7 +86,9 @@ static ssize_t qeth_bridge_port_role_store(struct device *dev,
 
        mutex_lock(&card->conf_mutex);
 
-       if (qeth_card_hw_is_reachable(card)) {
+       if (card->options.sbp.reflect_promisc) /* Forbid direct manipulation */
+               rc = -EPERM;
+       else if (qeth_card_hw_is_reachable(card)) {
                rc = qeth_bridgeport_setrole(card, role);
                if (!rc)
                        card->options.sbp.role = role;
@@ -184,6 +186,7 @@ static ssize_t qeth_bridgeport_reflect_store(struct device *dev,
 {
        struct qeth_card *card = dev_get_drvdata(dev);
        int enable, primary;
+       int rc = 0;
 
        if (!card)
                return -EINVAL;
@@ -202,12 +205,17 @@ static ssize_t qeth_bridgeport_reflect_store(struct device *dev,
 
        mutex_lock(&card->conf_mutex);
 
-       card->options.sbp.reflect_promisc = enable;
-       card->options.sbp.reflect_promisc_primary = primary;
+       if (card->options.sbp.role != QETH_SBP_ROLE_NONE)
+               rc = -EPERM;
+       else {
+               card->options.sbp.reflect_promisc = enable;
+               card->options.sbp.reflect_promisc_primary = primary;
+               rc = 0;
+       }
 
        mutex_unlock(&card->conf_mutex);
 
-       return count;
+       return rc ? rc : count;
 }
 
 static DEVICE_ATTR(bridge_reflect_promisc, 0644,