CVEvulnerability
CVE-2025-21781
5.5 MEDIUM
Official page ↗
- Status
- Modified
- Published
- 2025-02-27
- Last modified
- 2026-06-17
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 ([email protected])
- 5.5 MEDIUM — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Description
In the Linux kernel, the following vulnerability has been resolved:
batman-adv: fix panic during interface removal
Reference counting is used to ensure that
batadv_hardif_neigh_node and batadv_hard_iface
are not freed before/during
batadv_v_elp_throughput_metric_update work is
finished.
But there isn't a guarantee that the hard if will
remain associated with a soft interface up until
the work is finished.
This fixes a crash triggered by reboot that looks
like this:
Call trace:
batadv_v_mesh_free+0xd0/0x4dc [batman_adv]
batadv_v_elp_throughput_metric_update+0x1c/0xa4
process_one_work+0x178/0x398
worker_thread+0x2e8/0x4d0
kthread+0xd8/0xdc
ret_from_fork+0x10/0x20
(the batadv_v_mesh_free call is misleading,
and does not actually happen)
I was able to make the issue happen more reliably
by changing hardif_neigh->bat_v.metric_work work
to be delayed work. This allowed me to track down
and confirm the fix.
[[email protected]: prevent entering batadv_v_elp_get_throughput without
soft_iface]
Affected configurations
• linux linux kernel (>= 4.6 < 5.4.291)
• linux linux kernel (>= 5.5 < 5.10.235)
• linux linux kernel (>= 5.11 < 5.15.179)
• linux linux kernel (>= 5.16 < 6.1.129)
• linux linux kernel (>= 6.2 < 6.6.79)
• linux linux kernel (>= 6.7 < 6.12.16)
• linux linux kernel (>= 6.13 < 6.13.4)
• linux linux kernel 6.14
References
- https://git.kernel.org/stable/c/072b2787321903287a126c148e8db87dd7ef96fe Patch
- https://git.kernel.org/stable/c/167422a07096a6006599067c8b55884064fa0b72 Patch
- https://git.kernel.org/stable/c/2c3fb7df4cc6d043f70d4a8a10f8b915bbfb75e7 Patch
- https://git.kernel.org/stable/c/522b1596ea19e327853804da2de60aeb9c5d6f42 Patch
- https://git.kernel.org/stable/c/7eb5dd201695645af071592a50026eb780081a72 Patch
- https://git.kernel.org/stable/c/ccb7276a6d26d6f8416e315b43b45e15ee7f29e2 Patch
- https://git.kernel.org/stable/c/ce3f1545bf8fa28bd05ec113679e8e6cd23af577 Patch
- https://git.kernel.org/stable/c/f0a16c6c79768180333f3e41ce63f32730e3c3af Patch
- https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html lists.debian.org
- https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html lists.debian.org