Patch "igb: close/suspend race in netif_device_detach" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

igb: close/suspend race in netif_device_detach

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
igb-close-suspend-race-in-netif_device_detach.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Todd Fujinaka <[email protected]>
Date: Tue, 15 Nov 2016 08:54:26 -0800
Subject: igb: close/suspend race in netif_device_detach

From: Todd Fujinaka <[email protected]>

[ Upstream commit 9474933caf21a4cb5147223dca1551f527aaac36 ]

Similar to ixgbe, when an interface is part of a namespace it is possible that igb_close() may be called while __igb_shutdown() is running which ends up in a double free WARN and/or a BUG in free_msi_irqs().

Extend the rtnl_lock() to protect the call to netif_device_detach() and igb_clear_interrupt_scheme() in __igb_shutdown() and check for netif_device_present() to avoid calling igb_clear_interrupt_scheme() a second time in igb_close().

Also extend the rtnl lock in igb_resume() to netif_device_attach().

---
 drivers/net/ethernet/intel/igb/igb_main.c |   21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

@@ -3271,7 +3271,9 @@ static int __igb_close(struct net_device
 
 int igb_close(struct net_device *netdev)
 {
-	return __igb_close(netdev, false);
+	if (netif_device_present(netdev))
+		return __igb_close(netdev, false);
+	return 0;
 }
 
 /**

@@ -7548,6 +7550,7 @@ static int __igb_shutdown(struct pci_dev
 	int retval = 0;
 #endif
 
+	rtnl_lock();
 	netif_device_detach(netdev);
 
 	if (netif_running(netdev))

@@ -7556,6 +7559,7 @@ static int __igb_shutdown(struct pci_dev
 	igb_ptp_suspend(adapter);
 
 	igb_clear_interrupt_scheme(adapter);
+	rtnl_unlock();
 
 #ifdef CONFIG_PM
 	retval = pci_save_state(pdev);

@@ -7674,16 +7678,15 @@ static int igb_resume(struct device *dev
 
 	wr32(E1000_WUS, ~0);
 
-	if (netdev->flags & IFF_UP) {
-		rtnl_lock();
+	rtnl_lock();
+	if (!err && netif_running(netdev))
 		err = __igb_open(netdev, true);
-		rtnl_unlock();
-		if (err)
-			return err;
-	}
 
-	netif_device_attach(netdev);
-	return 0;
+	if (!err)
+		netif_device_attach(netdev);
+	rtnl_unlock();
+
+	return err;
 }
 
 static int igb_runtime_idle(struct device *dev)

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/igb-close-suspend-race-in-netif_device_detach.patch