[PATCH AUTOSEL 6.8 05/68] batman-adv: Improve exception handling in batadv_throw_uevent()

Sasha Levin
2024-03-29T12:27:00Z

From: Markus Elfring <elfring@users.sourceforge.net>

[ Upstream commit 5593e9abf1cf2bf096366d8c7fd933bc69d561ce ]

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>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <sashal@kernel.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 5fc754b0b3f7f..75119f1ffcccf 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