From 520c75dcae6e588670962243bac6324e7839b648 Mon Sep 17 00:00:00 2001 From: Matthias Schiffer Date: Sat, 24 Oct 2015 21:25:51 +0200 Subject: [PATCH] mac80211: fix crash on mesh local link ID generation with VIFs llid_in_use needs to be limited to stations of the same VIF, otherwise it will cause a NULL deref as the sta_info of non-mesh-VIFs don't have sta->mesh set. Steps to reproduce: modprobe mac80211_hwsim channels=2 iw phy phy0 interface add ibss0 type ibss iw phy phy0 interface add mesh0 type mp iw phy phy1 interface add ibss1 type ibss iw phy phy1 interface add mesh1 type mp ip link set ibss0 up ip link set mesh0 up ip link set ibss1 up ip link set mesh1 up iw dev ibss0 ibss join foo 2412 iw dev ibss1 ibss join foo 2412 # Ensure that ibss0 and ibss1 are actually associated; I often need to # leave and join the cell on ibss1 a second time. iw dev mesh0 mesh join bar iw dev mesh1 mesh join bar # crash Signed-off-by: Matthias Schiffer Signed-off-by: Johannes Berg --- net/mac80211/mesh_plink.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c index c1f889270484..bd3d55eb21d4 100644 --- a/net/mac80211/mesh_plink.c +++ b/net/mac80211/mesh_plink.c @@ -686,6 +686,9 @@ static bool llid_in_use(struct ieee80211_sub_if_data *sdata, rcu_read_lock(); list_for_each_entry_rcu(sta, &local->sta_list, list) { + if (sdata != sta->sdata) + continue; + if (!memcmp(&sta->mesh->llid, &llid, sizeof(llid))) { in_use = true; break; -- 2.20.1