CVE-2026-64218

In the Linux kernel, the following vulnerability has been resolved:

batman-adv: bla: fix report_work leak on backbone_gw purge

batadv_bla_purge_backbone_gw() removes stale backbone gateway entries,

but fails to properly handle their associated report_work:

- If report_work is running, the purge must wait for it to finish before

freeing the backbone_gw, otherwise the worker may access freed memory

(e.g. bat_priv).

- If report_work is pending, the purge must cancel it and release the

reference held for that pending work item.

The previous implementation called hlist_for_each_entry_safe() inside a

spin_lock_bh() section, but cancel_work_sync() may sleep and therefore

cannot be called from within a spinlock-protected region.

Restructure the loop to handle one entry per spinlock critical section:

acquire the lock, find the next entry to purge, remove it from the hash

list, then release the lock before calling cancel_work_sync() and

dropping the hash_entry reference. Repeat until no more entries require

purging.