In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: account proxy paths against the mesh path limit
Proxy-path churn can drive the interface path counter negative and let
later mesh path additions exceed MESH_MAX_MPATHS.
mesh_path_free_rcu() decrements the interface mpaths counter for entries
from both the mesh and proxy path tables, but mpp_path_add() never
reserves a slot in that counter. Removing or expiring a proxy path
therefore returns a slot that was never charged.
mesh_path_add() uses the same counter to enforce MESH_MAX_MPATHS, so once
it falls below the number of installed paths the limit no longer holds.
Reserve the shared quota before allocating a proxy path and release it on
every unsuccessful addition. Mesh and proxy paths now share one
1024-entry budget, so mpp_path_add() can return -ENOSPC at that limit.