Merge tag 'v5.0.17' into toradex_5.0.y

This is the 5.0.17 stable release

1 files changed, 15 insertions, 1 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 12824e007e06..7277dd393c00 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1184,7 +1184,21 @@ int dev_change_name(struct net_device *dev, const char *newname)
 	BUG_ON(!dev_net(dev));
 
 	net = dev_net(dev);
-	if (dev->flags & IFF_UP)
+
+	/* Some auto-enslaved devices e.g. failover slaves are
+	 * special, as userspace might rename the device after
+	 * the interface had been brought up and running since
+	 * the point kernel initiated auto-enslavement. Allow
+	 * live name change even when these slave devices are
+	 * up and running.
+	 *
+	 * Typically, users of these auto-enslaving devices
+	 * don't actually care about slave name change, as
+	 * they are supposed to operate on master interface
+	 * directly.
+	 */
+	if (dev->flags & IFF_UP &&
+	    likely(!(dev->priv_flags & IFF_LIVE_RENAME_OK)))
 		return -EBUSY;
 
 	write_seqcount_begin(&devnet_rename_seq);