batman-adv/patches/0045-batman-adv-Fix-refcnt-leak-in-batadv_v_ogm_process.patch

   1 From: Xiyu Yang <xiyuyang19@fudan.edu.cn>
   2 Date: Mon, 20 Apr 2020 13:37:20 +0800
   3 Subject: batman-adv: Fix refcnt leak in batadv_v_ogm_process
   4
   5 batadv_v_ogm_process() invokes batadv_hardif_neigh_get(), which returns
   6 a reference of the neighbor object to "hardif_neigh" with increased
   7 refcount.
   8
   9 When batadv_v_ogm_process() returns, "hardif_neigh" becomes invalid, so
  10 the refcount should be decreased to keep refcount balanced.
  11
  12 The reference counting issue happens in one exception handling paths of
  13 batadv_v_ogm_process(). When batadv_v_ogm_orig_get() fails to get the
  14 orig node and returns NULL, the refcnt increased by
  15 batadv_hardif_neigh_get() is not decreased, causing a refcnt leak.
  16
  17 Fix this issue by jumping to "out" label when batadv_v_ogm_orig_get()
  18 fails to get the orig node.
  19
  20 Fixes: 667996ebeab4 ("batman-adv: OGMv2 - implement originators logic")
  21 Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
  22 Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
  23 Signed-off-by: Sven Eckelmann <sven@narfation.org>
  24
  25 Origin: upstream, https://git.open-mesh.org/batman-adv.git/commit/4515f5e6a4ccbe1c563b05f2d487eb9eef3c9740
  26
  27 diff --git a/net/batman-adv/bat_v_ogm.c b/net/batman-adv/bat_v_ogm.c
  28 index bf9ea404abe7cbe1dd2113881856cd35b718b7d1..0458de53cb64b2da51de492ffa27f33068351cc8 100644
  29 --- a/net/batman-adv/bat_v_ogm.c
  30 +++ b/net/batman-adv/bat_v_ogm.c
  31 @@ -735,7 +735,7 @@ static void batadv_v_ogm_process(const struct sk_buff *skb, int ogm_offset,
  32
  33         orig_node = batadv_v_ogm_orig_get(bat_priv, ogm_packet->orig);
  34         if (!orig_node)
  35 -               return;
  36 +               goto out;
  37
  38         neigh_node = batadv_neigh_node_get_or_create(orig_node, if_incoming,
  39                                                      ethhdr->h_source);