github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-07-28 18:21:24 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

batman-adv: gw: don't deselect gateway with active hardif

Browse Source 
The batadv_hardif_cnt() was previously checking if there is an
batadv_hard_iface->mesh_iface which is has the same mesh_iface. And since
batadv_hardif_disable_interface() was resetting the
batadv_hard_iface->mesh_iface after this check, it had to verify whether
*1* interface was still part of the mesh_iface before it started the
gateway deselection.

But after batadv_hardif_cnt() is now checking the lower interfaces of
mesh_iface and batadv_hardif_disable_interface() already removed the
interface via netdev_upper_dev_unlink() earlier in this function, the check
must now make sure that *0* interfaces can be found by batadv_hardif_cnt()
before selected gateway must be deselected. Otherwise the deselection would
already happen one batadv_hard_iface too early.

Because a 0 hardif count from batadv_hardif_cnt() is equal to an empty
list, it is possible to replace the counting with a simple list_empty().

Cc: stable@kernel.org
Fixes: 7dc284702b ("batman-adv: store hard_iface as iflink private data")
Reviewed-by: Nora Schiffer <neocturne@universe-factory.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
This commit is contained in:
Sven Eckelmann 2026-06-07 14:34:28 +02:00
parent dad4d4b92a
commit df97a7107b
No known key found for this signature in database
GPG Key ID: 4D0F772BD314F5CB
1 changed files with 2 additions and 26 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
net/batman-adv/hard-interface.c
View File

@ -814,30 +814,6 @@ int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
return ret;
}
/**
* batadv_hardif_cnt() - get number of interfaces enslaved to mesh interface
* @mesh_iface: mesh interface to check
*
* This function is only using RCU for locking - the result can therefore be
* off when another function is modifying the list at the same time. The
* caller can use the rtnl_lock to make sure that the count is accurate.
*
* Return: number of connected/enslaved hard interfaces
*/
static size_t batadv_hardif_cnt(struct net_device *mesh_iface)
{
struct batadv_hard_iface *hard_iface;
struct list_head *iter;
size_t count = 0;
rcu_read_lock();
netdev_for_each_lower_private_rcu(mesh_iface, hard_iface, iter)
count++;
rcu_read_unlock();
return count;
}
/**
* batadv_hardif_disable_interface() - Remove hard interface from mesh interface
* @hard_iface: hard interface to be removed
@ -878,8 +854,8 @@ void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface)
netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->mesh_iface);
batadv_hardif_recalc_extra_skbroom(hard_iface->mesh_iface);
/* nobody uses this interface anymore */
if (batadv_hardif_cnt(hard_iface->mesh_iface) <= 1)
/* nobody uses this mesh interface anymore */
if (list_empty(&hard_iface->mesh_iface->adj_list.lower))
batadv_gw_check_client_stop(bat_priv);
hard_iface->mesh_iface = NULL;