bridge: add rcu_read_lock on transmit
Long ago, when bridge was converted to RCU, rcu lock was equivalent
to having preempt disabled. RCU has changed a lot since then and
bridge code was still assuming the since transmit was called with
bottom half disabled, it was RCU safe.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Tested-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c
index 753fc42..4cec805 100644
--- a/net/bridge/br_device.c
+++ b/net/bridge/br_device.c
@@ -22,7 +22,7 @@
#include <asm/uaccess.h>
#include "br_private.h"
-/* net device transmit always called with no BH (preempt_disabled) */
+/* net device transmit always called with BH disabled */
netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct net_bridge *br = netdev_priv(dev);
@@ -46,6 +46,7 @@
skb_reset_mac_header(skb);
skb_pull(skb, ETH_HLEN);
+ rcu_read_lock();
if (is_multicast_ether_addr(dest)) {
if (br_multicast_rcv(br, NULL, skb))
goto out;
@@ -61,6 +62,7 @@
br_flood_deliver(br, skb);
out:
+ rcu_read_unlock();
return NETDEV_TX_OK;
}
