[PATCH net-next] net: tls: reshuffle the device ops check

[Jakub Kicinski <kuba@kernel.org>]

We try to validate during registration that the netdev
has ops if it has features. This is currently somewhat sillily
written because we have a dereference before a NULL check
on the ops struct. Straighten this out.

No functional change intended other than saving ourselves
the very theoretical crash with a bad driver.

Note that we check earlier in the function that either ops
or TLS features are set for the device in question.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
CC: john.fastabend@gmail.com
CC: sd@queasysnail.net
---
 net/tls/tls_device.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index 99c8eff9783e..741aef09bfd3 100644
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -1387,16 +1387,15 @@ static int tls_dev_event(struct notifier_block *this, unsigned long event,
 	case NETDEV_FEAT_CHANGE:
 		if (netif_is_bond_master(dev))
 			return NOTIFY_DONE;
+		if  (!dev->tlsdev_ops ||
+		     !dev->tlsdev_ops->tls_dev_add ||
+		     !dev->tlsdev_ops->tls_dev_del)
+			return NOTIFY_BAD;
 		if ((dev->features & NETIF_F_HW_TLS_RX) &&
 		    !dev->tlsdev_ops->tls_dev_resync)
 			return NOTIFY_BAD;
 
-		if  (dev->tlsdev_ops &&
-		     dev->tlsdev_ops->tls_dev_add &&
-		     dev->tlsdev_ops->tls_dev_del)
-			return NOTIFY_DONE;
-		else
-			return NOTIFY_BAD;
+		return NOTIFY_DONE;
 	case NETDEV_DOWN:
 		return tls_device_down(dev);
 	}
-- 
2.54.0