batman-adv/patches/0003-batman-adv-Avoid-nullptr-derefence-in-batadv_v_neigh.patch

   1 From 036aa7b7181ee96ae6971eb31dd97b6ace7c0a80 Mon Sep 17 00:00:00 2001
   2 From: Sven Eckelmann <sven@narfation.org>
   3 Date: Fri, 6 May 2016 11:43:38 +0200
   4 Subject: [PATCH 3/6] batman-adv: Avoid nullptr derefence in
   5  batadv_v_neigh_is_sob
   6
   7 batadv_neigh_ifinfo_get can return NULL when it cannot find (even when only
   8 temporarily) anymore the neigh_ifinfo in the list neigh->ifinfo_list. This
   9 has to be checked to avoid kernel Oopses when the ifinfo is dereferenced.
  10
  11 This a situation which isn't expected but is already handled by functions
  12 like batadv_v_neigh_cmp. The same kind of warning is therefore used before
  13 the function returns without dereferencing the pointers.
  14
  15 Fixes: b05bbab5e1fc ("batman-adv: B.A.T.M.A.N. V - implement neighbor comparison API calls")
  16 Signed-off-by: Sven Eckelmann <sven@narfation.org>
  17 Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
  18 ---
  19  net/batman-adv/bat_v.c | 3 +++
  20  1 file changed, 3 insertions(+)
  21
  22 diff --git a/net/batman-adv/bat_v.c b/net/batman-adv/bat_v.c
  23 index 4547fce..7e1467a 100644
  24 --- a/net/batman-adv/bat_v.c
  25 +++ b/net/batman-adv/bat_v.c
  26 @@ -295,6 +295,9 @@ static bool batadv_v_neigh_is_sob(struct batadv_neigh_node *neigh1,
  27         ifinfo1 = batadv_neigh_ifinfo_get(neigh1, if_outgoing1);
  28         ifinfo2 = batadv_neigh_ifinfo_get(neigh2, if_outgoing2);
  29
  30 +       if (WARN_ON(!ifinfo1 || !ifinfo2))
  31 +               return false;
  32 +
  33         threshold = ifinfo1->bat_v.throughput / 4;
  34         threshold = ifinfo1->bat_v.throughput - threshold;
  35
  36 --
  37 2.8.0.rc3
  38