[B.A.T.M.A.N.] [PATCH 11/14] batman-adv: protect tt request from double deletion

Antonio Quartulli
2015-08-04T16:35:31Z

From: Marek Lindner <mareklindner@neomailbox.ch>

The list_del() calls were changed to list_del_init() to prevent
an accidental double deletion in batadv_tt_req_node_new().

Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
---
net/batman-adv/translation-table.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c
index cb2a2d1..db06de2 100644
--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c
@@ -2213,7 +2213,7 @@ static void batadv_tt_req_list_free(struct batadv_priv *bat_priv)
spin_lock_bh(&bat_priv->tt.req_list_lock);

list_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
- list_del(&node->list);
+ list_del_init(&node->list);
kfree(node);
}

@@ -2249,7 +2249,7 @@ static void batadv_tt_req_purge(struct batadv_priv *bat_priv)
list_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
if (batadv_has_timed_out(node->issued_at,
BATADV_TT_REQUEST_TIMEOUT)) {
- list_del(&node->list);
+ list_del_init(&node->list);
kfree(node);
}
}
@@ -2531,7 +2531,8 @@ out:
batadv_hardif_free_ref(primary_if);
if (ret && tt_req_node) {
spin_lock_bh(&bat_priv->tt.req_list_lock);
- list_del(&tt_req_node->list);
+ /* list_del_init() verifies tt_req_node still is in the list */
+ list_del_init(&tt_req_node->list);
spin_unlock_bh(&bat_priv->tt.req_list_lock);
kfree(tt_req_node);
}
@@ -2968,7 +2969,7 @@ static void batadv_handle_tt_response(struct batadv_priv *bat_priv,
list_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
if (!batadv_compare_eth(node->addr, resp_src))
continue;
- list_del(&node->list);
+ list_del_init(&node->list);
kfree(node);
}

--
2.5.0