Re: [PATCH net] ice: Fix freeing uninitialized pointers

[Markus Elfring]

> Automatically cleaned up pointers need to be initialized before exiting
> their scope.  In this case, they need to be initialized to NULL before
> any return statement.

How will development interests evolve further for such design aspects?


…
> +++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c
> @@ -941,11 +941,11 @@ static u64 ice_loopback_test(struct net_device *netdev)
>  	struct ice_netdev_priv *np = netdev_priv(netdev);
>  	struct ice_vsi *orig_vsi = np->vsi, *test_vsi;
>  	struct ice_pf *pf = orig_vsi->back;
> +	u8 *tx_frame __free(kfree) = NULL;
>  	u8 broadcast[ETH_ALEN], ret = 0;
>  	int num_frames, valid_frames;
>  	struct ice_tx_ring *tx_ring;
>  	struct ice_rx_ring *rx_ring;
> -	u8 *tx_frame __free(kfree);
>  	int i;
>
>  	netdev_info(netdev, "loopback test\n");

How do you think about to reduce the scope for the affected local variable instead
with the help of a small script (like the following) for the semantic patch language?

@movement@
attribute name __free;
@@
-u8 *tx_frame __free(kfree);
 int i;
 ... when any
 if (ice_fltr_add_mac(test_vsi, ...))
 { ... }
+
+{
+u8 *tx_frame __free(kfree) = NULL;
 if (ice_lbtest_create_frame(pf, &tx_frame, ...))
 { ... }
 ... when any
+}
+
 valid_frames = ice_lbtest_receive_frames(...);


Regards,
Markus