From fbfc8502af526578039dc89426224943d199c019 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Mon, 17 Feb 2020 14:02:36 -0600 Subject: net: switchdev: Replace zero-length array with flexible-array member The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva Signed-off-by: David S. Miller --- net/switchdev/switchdev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/switchdev/switchdev.c') diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c index 3a1d428c1336..60630762a748 100644 --- a/net/switchdev/switchdev.c +++ b/net/switchdev/switchdev.c @@ -29,7 +29,7 @@ struct switchdev_deferred_item { struct list_head list; struct net_device *dev; switchdev_deferred_func_t *func; - unsigned long data[0]; + unsigned long data[]; }; static struct switchdev_deferred_item *switchdev_deferred_dequeue(void) -- cgit v1.2.3 From 07c6f9805f12f1bb538ef165a092b300350384aa Mon Sep 17 00:00:00 2001 From: Russell King Date: Wed, 26 Feb 2020 17:14:21 +0000 Subject: net: switchdev: do not propagate bridge updates across bridges When configuring a tree of independent bridges, propagating changes from the upper bridge across a bridge master to the lower bridge ports brings surprises. For example, a lower bridge may have vlan filtering enabled. It may have a vlan interface attached to the bridge master, which may then be incorporated into another bridge. As soon as the lower bridge vlan interface is attached to the upper bridge, the lower bridge has vlan filtering disabled. This occurs because switchdev recursively applies its changes to all lower devices no matter what. Reviewed-by: Ido Schimmel Tested-by: Ido Schimmel Signed-off-by: Russell King Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- net/switchdev/switchdev.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'net/switchdev/switchdev.c') diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c index 60630762a748..f25604d68337 100644 --- a/net/switchdev/switchdev.c +++ b/net/switchdev/switchdev.c @@ -475,6 +475,9 @@ static int __switchdev_handle_port_obj_add(struct net_device *dev, * necessary to go through this helper. */ netdev_for_each_lower_dev(dev, lower_dev, iter) { + if (netif_is_bridge_master(lower_dev)) + continue; + err = __switchdev_handle_port_obj_add(lower_dev, port_obj_info, check_cb, add_cb); if (err && err != -EOPNOTSUPP) @@ -526,6 +529,9 @@ static int __switchdev_handle_port_obj_del(struct net_device *dev, * necessary to go through this helper. */ netdev_for_each_lower_dev(dev, lower_dev, iter) { + if (netif_is_bridge_master(lower_dev)) + continue; + err = __switchdev_handle_port_obj_del(lower_dev, port_obj_info, check_cb, del_cb); if (err && err != -EOPNOTSUPP) @@ -576,6 +582,9 @@ static int __switchdev_handle_port_attr_set(struct net_device *dev, * necessary to go through this helper. */ netdev_for_each_lower_dev(dev, lower_dev, iter) { + if (netif_is_bridge_master(lower_dev)) + continue; + err = __switchdev_handle_port_attr_set(lower_dev, port_attr_info, check_cb, set_cb); if (err && err != -EOPNOTSUPP) -- cgit v1.2.3