netifd: Fix device ifindex overwrite when processing netlink event messages

When a device with the same name is deleted and created again in the kernel
the ifindex changes.
A race condition will occur when netlink event messages linked to the old device
are processed and will thus overwrite the correct ifindex of the new device.
Further make sure a valid ifindex is in place for both external and internal
devices when setting the state to enabled.

Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/device.c b/device.c
index b29d73b..5d1dcac 100644
--- a/device.c
+++ b/device.c
@@ -62,6 +62,14 @@ void device_unlock(void)
 
 static int set_device_state(struct device *dev, bool state)
 {
+	if (state) {
+		/* Set ifindex for all devices being enabled so a valid  */
+		/* ifindex is in place avoiding possible race conditions */
+		device_set_ifindex(dev, system_if_resolve(dev));
+		if (!dev->ifindex)
+			return -1;
+	}
+
 	if (dev->external)
 		return 0;