mac802154: tx: don't allow if down while sync tx

This patch holds rtnl lock while sync xmit inside of workqueue.
Otherwise we could down the interface while worker xmit handling.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

1 files changed, 22 insertions, 9 deletions

diff --git a/net/mac802154/tx.c b/net/mac802154/tx.c
index 1a4f6d91ab8c..44390419af86 100644
--- a/net/mac802154/tx.c
+++ b/net/mac802154/tx.c
@@ -21,6 +21,7 @@
 #include <linux/if_arp.h>
 #include <linux/crc-ccitt.h>
 
+#include <net/rtnetlink.h>
 #include <net/ieee802154_netdev.h>
 #include <net/mac802154.h>
 #include <net/cfg802154.h>
@@ -50,16 +51,28 @@ static void mac802154_xmit_worker(struct work_struct *work)
         struct sk_buff *skb = cb->skb;
         int res;
 
+        rtnl_lock();
+
+        /* check if ifdown occurred while schedule */
+        if (!netif_running(skb->dev))
+                goto err_tx;
+
         res = local->ops->xmit_sync(&local->hw, skb);
-        if (res) {
-                pr_debug("transmission failed\n");
-                /* Restart the netif queue on each sub_if_data object. */
-                ieee802154_wake_queue(&local->hw);
-                kfree_skb(skb);
-        } else {
-                /* Restart the netif queue on each sub_if_data object. */
-                ieee802154_xmit_complete(&local->hw, skb);
-        }
+        if (res)
+                goto err_tx;
+
+        ieee802154_xmit_complete(&local->hw, skb);
+
+        rtnl_unlock();
+
+        return;
+
+err_tx:
+        /* Restart the netif queue on each sub_if_data object. */
+        ieee802154_wake_queue(&local->hw);
+        rtnl_unlock();
+        kfree_skb(skb);
+        pr_debug("transmission failed\n");
 }
 
 static netdev_tx_t