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| author | Sven Eckelmann <sven@narfation.org> | 2016-03-05 19:05:24 +0100 |
|---|---|---|
| committer | Antonio Quartulli <a@unstable.cc> | 2016-05-10 12:28:29 +0200 |
| commit | f0b94ebccd2b924237ca7a101da3db70c3a8f0f2 (patch) | |
| tree | 106e0a52eaeef4f4816542ed77566916cfe72d93 /net/batman-adv | |
| parent | batman-adv: Use kref_get for hard_iface subfunctions (diff) | |
| download | linux-f0b94ebccd2b924237ca7a101da3db70c3a8f0f2.tar.xz linux-f0b94ebccd2b924237ca7a101da3db70c3a8f0f2.zip | |
batman-adv: Use kref_get for _batadv_update_route
_batadv_update_route requires that the caller already has a valid reference
for neigh_node. It is therefore not possible that it has an reference
counter of 0 and was still given to this function
The kref_get function instead WARNs (with debug information) when the
reference counter would still be 0. This makes a bug in batman-adv better
visible because kref_get_unless_zero would have ignored this problem.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
Diffstat (limited to 'net/batman-adv')
| -rw-r--r-- | net/batman-adv/routing.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index 2ecfca246be4..b494e435686f 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -100,10 +100,6 @@ static void _batadv_update_route(struct batadv_priv *bat_priv, if (curr_router) batadv_neigh_node_put(curr_router); - /* increase refcount of new best neighbor */ - if (neigh_node && !kref_get_unless_zero(&neigh_node->refcount)) - neigh_node = NULL; - spin_lock_bh(&orig_node->neigh_list_lock); /* curr_router used earlier may not be the current orig_ifinfo->router * anymore because it was dereferenced outside of the neigh_list_lock @@ -114,6 +110,10 @@ static void _batadv_update_route(struct batadv_priv *bat_priv, */ curr_router = rcu_dereference_protected(orig_ifinfo->router, true); + /* increase refcount of new best neighbor */ + if (neigh_node) + kref_get(&neigh_node->refcount); + rcu_assign_pointer(orig_ifinfo->router, neigh_node); spin_unlock_bh(&orig_node->neigh_list_lock); batadv_orig_ifinfo_put(orig_ifinfo); |