CVE-2026-31657

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

batman-adv: hold claim backbone gateways by reference

batadv_bla_add_claim() can replace claim->backbone_gw and drop the old

gateway's last reference while readers still follow the pointer.

The netlink claim dump path dereferences claim->backbone_gw->orig and

takes claim->backbone_gw->crc_lock without pinning the underlying

backbone gateway. batadv_bla_check_claim() still has the same naked

pointer access pattern.

Reuse batadv_bla_claim_get_backbone_gw() in both readers so they operate

on a stable gateway reference until the read-side work is complete.

This keeps the dump and claim-check paths aligned with the lifetime

rules introduced for the other BLA claim readers.