batman-adv: Merge bugfixes from 2025.2

* fix duplicate MAC address check

Signed-off-by: Sven Eckelmann <[email protected]>

diff --git a/batman-adv/Makefile b/batman-adv/Makefile
index eb09bca71218a4352d77ced31b979f6626ec94b7..4eae4b20d42174d85bbc9ee330630766213ca7f6 100644 (file)
--- a/batman-adv/Makefile
+++ b/batman-adv/Makefile
@@ -4,7 +4,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=batman-adv
 PKG_VERSION:=2023.1
-PKG_RELEASE:=11
+PKG_RELEASE:=12
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
 PKG_SOURCE_URL:=https://downloads.open-mesh.org/batman/releases/batman-adv-$(PKG_VERSION)

diff --git a/batman-adv/patches/0020-batman-adv-fix-duplicate-MAC-address-check.patch b/batman-adv/patches/0020-batman-adv-fix-duplicate-MAC-address-check.patch
new file mode 100644 (file)
index 0000000..da41e14
--- /dev/null
+++ b/batman-adv/patches/0020-batman-adv-fix-duplicate-MAC-address-check.patch
@@ -0,0 +1,105 @@
+From: Matthias Schiffer <[email protected]>
+Date: Wed, 16 Apr 2025 20:37:56 +0200
+Subject: batman-adv: fix duplicate MAC address check
+
+batadv_check_known_mac_addr() is both too lenient and too strict:
+
+- It is called from batadv_hardif_add_interface(), which means that it
+  checked interfaces that are not used for batman-adv at all. Move it
+  to batadv_hardif_enable_interface(). Also, restrict it to hardifs of
+  the same mesh interface; different mesh interfaces should not interact
+  at all. The batadv_check_known_mac_addr() argument is changed from
+  `struct net_device` to `struct batadv_hard_iface` to achieve this.
+- The check only cares about hardifs in BATADV_IF_ACTIVE and
+  BATADV_IF_TO_BE_ACTIVATED states, but interfaces in BATADV_IF_INACTIVE
+  state should be checked as well, or the following steps will not
+  result in a warning then they should:
+
+  - Add two interfaces in down state with different MAC addresses to
+    a mesh as hardifs
+  - Change the MAC addresses so they conflict
+  - Set interfaces to up state
+
+  Now there will be two active hardifs with the same MAC address, but no
+  warning. Fix by only ignoring hardifs in BATADV_IF_NOT_IN_USE state.
+
+The RCU lock can be dropped, as we're holding RTNL anyways when the
+function is called.
+
+Fixes: c7560658b16b ("[batman-adv] print a warning when an existing mac address is added again")
+Signed-off-by: Matthias Schiffer <[email protected]>
+Signed-off-by: Sven Eckelmann <[email protected]>
+(cherry picked from commit 4a2b85600c38876b6c76eb7e75d76aef2c60a055)
+
+--- a/net/batman-adv/hard-interface.c
++++ b/net/batman-adv/hard-interface.c
+@@ -504,28 +504,32 @@ batadv_hardif_is_iface_up(const struct b
+       return false;
+ }
+ 
+-static void batadv_check_known_mac_addr(const struct net_device *net_dev)
++static void batadv_check_known_mac_addr(const struct batadv_hard_iface *hard_iface)
+ {
+-      const struct batadv_hard_iface *hard_iface;
++      const struct net_device *soft_iface = hard_iface->soft_iface;
++      const struct batadv_hard_iface *tmp_hard_iface;
+ 
+-      rcu_read_lock();
+-      list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
+-              if (hard_iface->if_status != BATADV_IF_ACTIVE &&
+-                  hard_iface->if_status != BATADV_IF_TO_BE_ACTIVATED)
++      if (!soft_iface)
++              return;
++
++      list_for_each_entry(tmp_hard_iface, &batadv_hardif_list, list) {
++              if (tmp_hard_iface == hard_iface)
++                      continue;
++
++              if (tmp_hard_iface->soft_iface != soft_iface)
+                       continue;
+ 
+-              if (hard_iface->net_dev == net_dev)
++              if (tmp_hard_iface->if_status == BATADV_IF_NOT_IN_USE)
+                       continue;
+ 
+-              if (!batadv_compare_eth(hard_iface->net_dev->dev_addr,
+-                                      net_dev->dev_addr))
++              if (!batadv_compare_eth(tmp_hard_iface->net_dev->dev_addr,
++                                      hard_iface->net_dev->dev_addr))
+                       continue;
+ 
+               pr_warn("The newly added mac address (%pM) already exists on: %s\n",
+-                      net_dev->dev_addr, hard_iface->net_dev->name);
++                      hard_iface->net_dev->dev_addr, tmp_hard_iface->net_dev->name);
+               pr_warn("It is strongly recommended to keep mac addresses unique to avoid problems!\n");
+       }
+-      rcu_read_unlock();
+ }
+ 
+ /**
+@@ -758,6 +762,8 @@ int batadv_hardif_enable_interface(struc
+                           hard_iface->net_dev->name, hard_iface->net_dev->mtu,
+                           ETH_DATA_LEN + max_header_len);
+ 
++      batadv_check_known_mac_addr(hard_iface);
++
+       if (batadv_hardif_is_iface_up(hard_iface))
+               batadv_hardif_activate_interface(hard_iface);
+       else
+@@ -896,7 +902,6 @@ batadv_hardif_add_interface(struct net_d
+ 
+       batadv_v_hardif_init(hard_iface);
+ 
+-      batadv_check_known_mac_addr(hard_iface->net_dev);
+       kref_get(&hard_iface->refcount);
+       list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
+       batadv_hardif_generation++;
+@@ -988,7 +993,7 @@ static int batadv_hard_if_event(struct n
+               if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
+                       goto hardif_put;
+ 
+-              batadv_check_known_mac_addr(hard_iface->net_dev);
++              batadv_check_known_mac_addr(hard_iface);
+ 
+               bat_priv = netdev_priv(hard_iface->soft_iface);
+               bat_priv->algo_ops->iface.update_mac(hard_iface);