[2/2] batman-adv: Improve exception handling in batadv_throw_uevent()
Commit Message
From: Markus Elfring <elfring@users.sourceforge.net>
Date: Tue, 2 Jan 2024 07:52:21 +0100
The kfree() function was called in up to three cases by
the batadv_throw_uevent() function during error handling
even if the passed variable contained a null pointer.
This issue was detected by using the Coccinelle software.
* Thus adjust jump targets.
* Reorder kfree() calls at the end.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
---
net/batman-adv/main.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
--
2.43.0
Comments
On Tuesday, 2 January 2024 08:12:56 CET Markus Elfring wrote:
> From: Markus Elfring <elfring@users.sourceforge.net>
> Date: Tue, 2 Jan 2024 07:52:21 +0100
>
> The kfree() function was called in up to three cases by
> the batadv_throw_uevent() function during error handling
> even if the passed variable contained a null pointer.
> This issue was detected by using the Coccinelle software.
>
> * Thus adjust jump targets.
>
> * Reorder kfree() calls at the end.
>
> Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Sven Eckelmann <sven@narfation.org>
> ---
> net/batman-adv/main.c | 14 ++++++++------
> 1 file changed, 8 insertions(+), 6 deletions(-)
>
> diff --git a/net/batman-adv/main.c b/net/batman-adv/main.c
> index 5fc754b0b3f7..75119f1ffccc 100644
> --- a/net/batman-adv/main.c
> +++ b/net/batman-adv/main.c
> @@ -691,29 +691,31 @@ int batadv_throw_uevent(struct batadv_priv *bat_priv, enum batadv_uev_type type,
> "%s%s", BATADV_UEV_TYPE_VAR,
> batadv_uev_type_str[type]);
> if (!uevent_env[0])
> - goto out;
> + goto report_error;
>
> uevent_env[1] = kasprintf(GFP_ATOMIC,
> "%s%s", BATADV_UEV_ACTION_VAR,
> batadv_uev_action_str[action]);
> if (!uevent_env[1])
> - goto out;
> + goto free_first_env;
>
> /* If the event is DEL, ignore the data field */
> if (action != BATADV_UEV_DEL) {
> uevent_env[2] = kasprintf(GFP_ATOMIC,
> "%s%s", BATADV_UEV_DATA_VAR, data);
> if (!uevent_env[2])
> - goto out;
> + goto free_second_env;
> }
>
> ret = kobject_uevent_env(bat_kobj, KOBJ_CHANGE, uevent_env);
> -out:
> - kfree(uevent_env[0]);
> - kfree(uevent_env[1]);
> kfree(uevent_env[2]);
> +free_second_env:
> + kfree(uevent_env[1]);
> +free_first_env:
> + kfree(uevent_env[0]);
>
> if (ret)
> +report_error:
> batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
> "Impossible to send uevent for (%s,%s,%s) event (err: %d)\n",
> batadv_uev_type_str[type],
> --
> 2.43.0
>
>
@@ -691,29 +691,31 @@ int batadv_throw_uevent(struct batadv_priv *bat_priv, enum batadv_uev_type type,
"%s%s", BATADV_UEV_TYPE_VAR,
batadv_uev_type_str[type]);
if (!uevent_env[0])
- goto out;
+ goto report_error;
uevent_env[1] = kasprintf(GFP_ATOMIC,
"%s%s", BATADV_UEV_ACTION_VAR,
batadv_uev_action_str[action]);
if (!uevent_env[1])
- goto out;
+ goto free_first_env;
/* If the event is DEL, ignore the data field */
if (action != BATADV_UEV_DEL) {
uevent_env[2] = kasprintf(GFP_ATOMIC,
"%s%s", BATADV_UEV_DATA_VAR, data);
if (!uevent_env[2])
- goto out;
+ goto free_second_env;
}
ret = kobject_uevent_env(bat_kobj, KOBJ_CHANGE, uevent_env);
-out:
- kfree(uevent_env[0]);
- kfree(uevent_env[1]);
kfree(uevent_env[2]);
+free_second_env:
+ kfree(uevent_env[1]);
+free_first_env:
+ kfree(uevent_env[0]);
if (ret)
+report_error:
batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
"Impossible to send uevent for (%s,%s,%s) event (err: %d)\n",
batadv_uev_type_str[type],