[PATCH 4.4 24/59] igb: close/suspend race in netif_device_detach

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Todd Fujinaka <todd.fujinaka@xxxxxxxxx>


[ 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().

Signed-off-by: Todd Fujinaka <todd.fujinaka@xxxxxxxxx>
Acked-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx>
Tested-by: Aaron Brown <aaron.f.brown@xxxxxxxxx>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@xxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/intel/igb/igb_main.c |   21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -3172,7 +3172,9 @@ static int __igb_close(struct net_device
 
 static int igb_close(struct net_device *netdev)
 {
-	return __igb_close(netdev, false);
+	if (netif_device_present(netdev))
+		return __igb_close(netdev, false);
+	return 0;
 }
 
 /**
@@ -7325,12 +7327,14 @@ static int __igb_shutdown(struct pci_dev
 	int retval = 0;
 #endif
 
+	rtnl_lock();
 	netif_device_detach(netdev);
 
 	if (netif_running(netdev))
 		__igb_close(netdev, true);
 
 	igb_clear_interrupt_scheme(adapter);
+	rtnl_unlock();
 
 #ifdef CONFIG_PM
 	retval = pci_save_state(pdev);
@@ -7450,16 +7454,15 @@ 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)