batman-adv: Merge bugfixes from 2019.2

[feed/routing.git] / batman-adv / patches / 0030-batman-adv-mcast-fix-multicast-tt-tvlv-worker-lockin.patch

diff --git a/batman-adv/patches/0030-batman-adv-mcast-fix-multicast-tt-tvlv-worker-lockin.patch b/batman-adv/patches/0030-batman-adv-mcast-fix-multicast-tt-tvlv-worker-lockin.patch
new file mode 100644 (file)
index 0000000..3f3f3d9
--- /dev/null
+++ b/batman-adv/patches/0030-batman-adv-mcast-fix-multicast-tt-tvlv-worker-lockin.patch
@@ -0,0 +1,103 @@
+From: Linus Lüssing <linus.luessing@c0d3.blue>
+Date: Wed, 24 Apr 2019 03:19:14 +0200
+Subject: batman-adv: mcast: fix multicast tt/tvlv worker locking
+
+Syzbot has reported some issues with the locking assumptions made for
+the multicast tt/tvlv worker: It was able to trigger the WARN_ON() in
+batadv_mcast_mla_tt_retract() and batadv_mcast_mla_tt_add().
+While hard/not reproduceable for us so far it seems that the
+delayed_work_pending() we use might not be quite safe from reordering.
+
+Therefore this patch adds an explicit, new spinlock to protect the
+update of the mla_list and flags in bat_priv and then removes the
+WARN_ON(delayed_work_pending()).
+
+Reported-by: syzbot+83f2d54ec6b7e417e13f@syzkaller.appspotmail.com
+Reported-by: syzbot+050927a651272b145a5d@syzkaller.appspotmail.com
+Reported-by: syzbot+979ffc89b87309b1b94b@syzkaller.appspotmail.com
+Reported-by: syzbot+f9f3f388440283da2965@syzkaller.appspotmail.com
+Fixes: 40b384052672 ("batman-adv: Use own timer for multicast TT and TVLV updates")
+Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
+Signed-off-by: Sven Eckelmann <sven@narfation.org>
+
+Origin: upstream, https://git.open-mesh.org/batman-adv.git/commit/b736cf8119cfbc9d95fef90c8832fdec6e8f29c7
+
+diff --git a/net/batman-adv/main.c b/net/batman-adv/main.c
+index 53b329d24461819b4cf0d4118cfa5b0eb8d7261b..0286c651468443197434ccf0fcf25aaa66a0c7e9 100644
+--- a/net/batman-adv/main.c
++++ b/net/batman-adv/main.c
+@@ -160,6 +160,7 @@ int batadv_mesh_init(struct net_device *soft_iface)
+       spin_lock_init(&bat_priv->tt.commit_lock);
+       spin_lock_init(&bat_priv->gw.list_lock);
+ #ifdef CONFIG_BATMAN_ADV_MCAST
++      spin_lock_init(&bat_priv->mcast.mla_lock);
+       spin_lock_init(&bat_priv->mcast.want_lists_lock);
+ #endif
+       spin_lock_init(&bat_priv->tvlv.container_list_lock);
+diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c
+index a35f597e8c8bf4f15ad0f01aff29849d2bebe36f..39640d3d6fbdf8244344db6e79f2d769eb0972d9 100644
+--- a/net/batman-adv/multicast.c
++++ b/net/batman-adv/multicast.c
+@@ -325,8 +325,6 @@ static void batadv_mcast_mla_list_free(struct hlist_head *mcast_list)
+  * translation table except the ones listed in the given mcast_list.
+  *
+  * If mcast_list is NULL then all are retracted.
+- *
+- * Do not call outside of the mcast worker! (or cancel mcast worker first)
+  */
+ static void batadv_mcast_mla_tt_retract(struct batadv_priv *bat_priv,
+                                       struct hlist_head *mcast_list)
+@@ -334,8 +332,6 @@ static void batadv_mcast_mla_tt_retract(struct batadv_priv *bat_priv,
+       struct batadv_hw_addr *mcast_entry;
+       struct hlist_node *tmp;
+ 
+-      WARN_ON(delayed_work_pending(&bat_priv->mcast.work));
+-
+       hlist_for_each_entry_safe(mcast_entry, tmp, &bat_priv->mcast.mla_list,
+                                 list) {
+               if (mcast_list &&
+@@ -359,8 +355,6 @@ static void batadv_mcast_mla_tt_retract(struct batadv_priv *bat_priv,
+  *
+  * Adds multicast listener announcements from the given mcast_list to the
+  * translation table if they have not been added yet.
+- *
+- * Do not call outside of the mcast worker! (or cancel mcast worker first)
+  */
+ static void batadv_mcast_mla_tt_add(struct batadv_priv *bat_priv,
+                                   struct hlist_head *mcast_list)
+@@ -368,8 +362,6 @@ static void batadv_mcast_mla_tt_add(struct batadv_priv *bat_priv,
+       struct batadv_hw_addr *mcast_entry;
+       struct hlist_node *tmp;
+ 
+-      WARN_ON(delayed_work_pending(&bat_priv->mcast.work));
+-
+       if (!mcast_list)
+               return;
+ 
+@@ -658,7 +650,10 @@ static void batadv_mcast_mla_update(struct work_struct *work)
+       priv_mcast = container_of(delayed_work, struct batadv_priv_mcast, work);
+       bat_priv = container_of(priv_mcast, struct batadv_priv, mcast);
+ 
++      spin_lock(&bat_priv->mcast.mla_lock);
+       __batadv_mcast_mla_update(bat_priv);
++      spin_unlock(&bat_priv->mcast.mla_lock);
++
+       batadv_mcast_start_timer(bat_priv);
+ }
+ 
+diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
+index 476b052ad9824d4cbcd6218dce40b603e3400fd2..6d07898d8d1a21007b3e68d5d2511b478110f659 100644
+--- a/net/batman-adv/types.h
++++ b/net/batman-adv/types.h
+@@ -1215,6 +1215,11 @@ struct batadv_priv_mcast {
+       /** @num_disabled: number of nodes that have no mcast tvlv */
+       atomic_t num_disabled;
+ 
++      /**
++       * @mla_lock: a lock protecting mla_list and mla_flags
++       */
++      spinlock_t mla_lock;
++
+       /**
+        * @num_want_all_unsnoopables: number of nodes wanting unsnoopable IP
+        *  traffic