CVE-2026-64096

Description

In the Linux kernel, the following vulnerability has been resolved: batman-adv: mcast: fix use-after-free in orig_node RCU release batadv_mcast_purge_orig() removes entries from RCU-protected hlists but does not wait for an RCU grace period before returning. Concurrent RCU readers may still accesses references to those entries at the point of removal. RCU-protected readers trying to operate on entries like orig->mcast_want_all_ipv6_node will then access already freed memory. Fix this by moving batadv_mcast_purge_orig() to batadv_orig_node_release(), just before the call_rcu() invocation. This ensures RCU readers that were active at purge time have drained before the orig_node memory is reclaimed.

References

• https://git.kernel.org/stable/c/20c2d6a20ca936f5aaa6dd40f73f262ac45c87cc
• https://git.kernel.org/stable/c/70bcb678561f0fb58f33270fc73f12f3be72b878
• https://git.kernel.org/stable/c/78a63fb2f7d5630d1c1f2859a20d4e4226863b41
• https://git.kernel.org/stable/c/8a3707653ab658e082ccd992e92594e01b09a3fc
• https://git.kernel.org/stable/c/aef897c9d2dd0d9339167fb82b62beff68d076cb