Description
In the Linux kernel, the following vulnerability has been resolved:
mac802154: fix use-after-free of sdata via queued RX frames
The RX softirq producer ieee802154_subif_frame() queues received beacon
and MAC-command frames onto local->rx_beacon_list / rx_mac_cmd_list and
schedules a process-context worker, storing a raw mac_pkt->sdata (and
skb->dev == sdata->dev) with neither a reference nor any locking:
- the lists have no lock: the softirq producer list_add_tail()s while the
mac_wq worker list_del()s, so sibling interfaces on the same phy corrupt
the list;
- the workers dereference the interface after it may have been freed.
mac802154_rx_mac_cmd_worker() touches mac_pkt->sdata directly, and
mac802154_rx_beacon_worker() -> mac802154_process_beacon() dereferences
skb->dev (== sdata->dev). Removing an interface frees its sdata
(netdev_priv) while a queued frame still points at it, so a later worker
run is a use-after-free.
Reproduced under KASAN by flooding a victim interface with MAC command
frames and removing it (the beacon path is the same class via skb->dev):
BUG: KASAN: slab-use-after-free in mac802154_rx_mac_cmd_worker+0x463/0x630 [mac802154]
Read of size 4 at addr ffff888002f9ea18 by task kworker/u8:1/31
Workqueue: phy0-mac-cmds mac802154_rx_mac_cmd_worker [mac802154]
Call Trace:
mac802154_rx_mac_cmd_worker+0x463/0x630 [mac802154]
process_one_work+0x611/0xe80
worker_thread+0x52e/0xdc0
kthread+0x30c/0x630
ret_from_fork+0x2fd/0x3e0
Fix both lists together:
- add local->rx_lock and take it around every list access: the softirq
producer (plain spin_lock, softirq context) and the workers and flush
(spin_lock_bh, process context);
- pin the interface for the lifetime of a queued frame with
netdev_hold()/netdev_put(), so the worker can safely dereference sdata /
skb->dev even while the interface is being removed;
- dequeue under the lock at the head and loop-drain the whole list in the
workers (they previously processed one frame per run and relied on a
later enqueue to drain the rest);
- drop not-yet-started frames of an interface before it is unregistered,
from ieee802154_if_remove() (after the RCU grace period) and from the
ieee802154_remove_interfaces() loop -- the latter is the whole-phy
teardown path, which does not go through ieee802154_if_remove().
An in-flight worker that already dequeued a frame keeps its own netdev
reference; unregister_netdevice() then waits it out in netdev_run_todo(),
which runs at rtnl_unlock() (rtnl released) and after the interface has
been closed, so it does not pin rtnl. A worker blocked in an association
TX only delays that one interface's unregister (the usual "waiting for %s
to become free"), it does not hold rtnl. netdev_hold() is used for this
reason instead of a cancel_work_sync() under rtnl, which would block on
the worker's unbounded MLME TX wait via ieee802154_sync_queue().
The mac-command worker additionally skips processing for a stopped
interface (ieee802154_sdata_running()), avoiding a needless association
response during teardown.
mac802154: fix use-after-free of sdata via queued RX frames
The RX softirq producer ieee802154_subif_frame() queues received beacon
and MAC-command frames onto local->rx_beacon_list / rx_mac_cmd_list and
schedules a process-context worker, storing a raw mac_pkt->sdata (and
skb->dev == sdata->dev) with neither a reference nor any locking:
- the lists have no lock: the softirq producer list_add_tail()s while the
mac_wq worker list_del()s, so sibling interfaces on the same phy corrupt
the list;
- the workers dereference the interface after it may have been freed.
mac802154_rx_mac_cmd_worker() touches mac_pkt->sdata directly, and
mac802154_rx_beacon_worker() -> mac802154_process_beacon() dereferences
skb->dev (== sdata->dev). Removing an interface frees its sdata
(netdev_priv) while a queued frame still points at it, so a later worker
run is a use-after-free.
Reproduced under KASAN by flooding a victim interface with MAC command
frames and removing it (the beacon path is the same class via skb->dev):
BUG: KASAN: slab-use-after-free in mac802154_rx_mac_cmd_worker+0x463/0x630 [mac802154]
Read of size 4 at addr ffff888002f9ea18 by task kworker/u8:1/31
Workqueue: phy0-mac-cmds mac802154_rx_mac_cmd_worker [mac802154]
Call Trace:
mac802154_rx_mac_cmd_worker+0x463/0x630 [mac802154]
process_one_work+0x611/0xe80
worker_thread+0x52e/0xdc0
kthread+0x30c/0x630
ret_from_fork+0x2fd/0x3e0
Fix both lists together:
- add local->rx_lock and take it around every list access: the softirq
producer (plain spin_lock, softirq context) and the workers and flush
(spin_lock_bh, process context);
- pin the interface for the lifetime of a queued frame with
netdev_hold()/netdev_put(), so the worker can safely dereference sdata /
skb->dev even while the interface is being removed;
- dequeue under the lock at the head and loop-drain the whole list in the
workers (they previously processed one frame per run and relied on a
later enqueue to drain the rest);
- drop not-yet-started frames of an interface before it is unregistered,
from ieee802154_if_remove() (after the RCU grace period) and from the
ieee802154_remove_interfaces() loop -- the latter is the whole-phy
teardown path, which does not go through ieee802154_if_remove().
An in-flight worker that already dequeued a frame keeps its own netdev
reference; unregister_netdevice() then waits it out in netdev_run_todo(),
which runs at rtnl_unlock() (rtnl released) and after the interface has
been closed, so it does not pin rtnl. A worker blocked in an association
TX only delays that one interface's unregister (the usual "waiting for %s
to become free"), it does not hold rtnl. netdev_hold() is used for this
reason instead of a cancel_work_sync() under rtnl, which would block on
the worker's unbounded MLME TX wait via ieee802154_sync_queue().
The mac-command worker additionally skips processing for a stopped
interface (ieee802154_sdata_running()), avoiding a needless association
response during teardown.
Published:
2026-09-25
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
Analysis
No analysis available yet.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
|
|||||||||||||||||||||
| Linux | Linux | affected |
|
No data.
No data.
No data available yet.
Remediation
No remediation available yet.
Tracking
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Advisories
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References
History
Fri, 25 Sep 2026 10:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: mac802154: fix use-after-free of sdata via queued RX frames The RX softirq producer ieee802154_subif_frame() queues received beacon and MAC-command frames onto local->rx_beacon_list / rx_mac_cmd_list and schedules a process-context worker, storing a raw mac_pkt->sdata (and skb->dev == sdata->dev) with neither a reference nor any locking: - the lists have no lock: the softirq producer list_add_tail()s while the mac_wq worker list_del()s, so sibling interfaces on the same phy corrupt the list; - the workers dereference the interface after it may have been freed. mac802154_rx_mac_cmd_worker() touches mac_pkt->sdata directly, and mac802154_rx_beacon_worker() -> mac802154_process_beacon() dereferences skb->dev (== sdata->dev). Removing an interface frees its sdata (netdev_priv) while a queued frame still points at it, so a later worker run is a use-after-free. Reproduced under KASAN by flooding a victim interface with MAC command frames and removing it (the beacon path is the same class via skb->dev): BUG: KASAN: slab-use-after-free in mac802154_rx_mac_cmd_worker+0x463/0x630 [mac802154] Read of size 4 at addr ffff888002f9ea18 by task kworker/u8:1/31 Workqueue: phy0-mac-cmds mac802154_rx_mac_cmd_worker [mac802154] Call Trace: mac802154_rx_mac_cmd_worker+0x463/0x630 [mac802154] process_one_work+0x611/0xe80 worker_thread+0x52e/0xdc0 kthread+0x30c/0x630 ret_from_fork+0x2fd/0x3e0 Fix both lists together: - add local->rx_lock and take it around every list access: the softirq producer (plain spin_lock, softirq context) and the workers and flush (spin_lock_bh, process context); - pin the interface for the lifetime of a queued frame with netdev_hold()/netdev_put(), so the worker can safely dereference sdata / skb->dev even while the interface is being removed; - dequeue under the lock at the head and loop-drain the whole list in the workers (they previously processed one frame per run and relied on a later enqueue to drain the rest); - drop not-yet-started frames of an interface before it is unregistered, from ieee802154_if_remove() (after the RCU grace period) and from the ieee802154_remove_interfaces() loop -- the latter is the whole-phy teardown path, which does not go through ieee802154_if_remove(). An in-flight worker that already dequeued a frame keeps its own netdev reference; unregister_netdevice() then waits it out in netdev_run_todo(), which runs at rtnl_unlock() (rtnl released) and after the interface has been closed, so it does not pin rtnl. A worker blocked in an association TX only delays that one interface's unregister (the usual "waiting for %s to become free"), it does not hold rtnl. netdev_hold() is used for this reason instead of a cancel_work_sync() under rtnl, which would block on the worker's unbounded MLME TX wait via ieee802154_sync_queue(). The mac-command worker additionally skips processing for a stopped interface (ieee802154_sdata_running()), avoiding a needless association response during teardown. | |
| Title | mac802154: fix use-after-free of sdata via queued RX frames | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-25T10:22:11.134Z
Reserved: 2026-09-24T16:01:01.157Z
Link: CVE-2026-97595
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-09-25T11:17:10.770
Modified: 2026-09-25T11:17:10.770
Link: CVE-2026-97595
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.