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

From: Markus Elfring
Date: Wed Mar 20 2024 - 08:19:28 EST


> 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.

I suggest to reconsider such information a bit more.



> +++ b/drivers/net/ethernet/intel/ice/ice_common.c
> @@ -1002,8 +1002,8 @@ static void ice_get_itr_intrl_gran(struct ice_hw *hw)
> */
> int ice_init_hw(struct ice_hw *hw)
> {
> - struct ice_aqc_get_phy_caps_data *pcaps __free(kfree);
> - void *mac_buf __free(kfree);
> + struct ice_aqc_get_phy_caps_data *pcaps __free(kfree) = NULL;
> + void *mac_buf __free(kfree) = NULL;
> u16 mac_buf_len;
> int status;

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


@movement1@
attribute name __free;
@@
-struct ice_aqc_get_phy_caps_data *pcaps __free(kfree);
... when any
+struct ice_aqc_get_phy_caps_data *
pcaps
+__free(kfree)
= kzalloc(sizeof(*pcaps), ...);

@movement2@
attribute name __free;
@@
-void *mac_buf __free(kfree);
... when any
+void *
mac_buf
+__free(kfree)
= kcalloc(2, sizeof(struct ice_aqc_manage_mac_read_resp), ...);


Regards,
Markus