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2026-09-03mac802154: fix use-after-free of sdata via queued RX framesIbrahim Hashimov
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. Fixes: 57588c71177f ("mac802154: Handle passive scanning") Cc: stable@vger.kernel.org Signed-off-by: Ibrahim Hashimov <security@auditcode.ai> Assisted-by: AuditCode-AI:2026.07 Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/20260725135154.99876-1-security@auditcode.ai Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
2026-09-01mac802154: fix data race and NULL deref on local->assoc_devKaiwen Shi
local->assoc_dev is shared between the association path and the association-response worker without common synchronization. mac802154_perform_association() stores the coordinator pointer and waits for a response. Its timeout and error paths clear the pointer and return to mac802154_associate(), which may then free the coordinator object. Meanwhile, mac802154_rx_mac_cmd_worker() may observe the associating bit and enter mac802154_process_association_resp(), which dereferences assoc_dev. The worker's bit test and the handler's pointer dereference are not atomic with respect to cleanup. Cleanup can clear assoc_dev between them, causing a NULL dereference, or free the coordinator while the response handler still uses the pointer. The recorded result is exposed to the same window. assoc_status and assoc_addr are written by the handler but read by the association path while the associating bit is still set, so a second response for the same request - a malicious one, for instance - can replace them between those reads and leave the caller with an incoherent status and address pair. The response handler only needs the coordinator extended address. Replace assoc_dev with a cached address, removing the pointer lifetime dependency. Protect the cached address and the associating bit with a dedicated spinlock. A READ_ONCE()/WRITE_ONCE() pair would not guarantee an atomic __le64 access on all 32-bit architectures. wpan_dev->association_lock cannot be reused here: nl802154_associate() holds it across rdev_associate(), hence for the whole of mac802154_perform_association() including the wait for the response. A response handler taking that lock would only get it once the association has already given up. Reset the completion, publish the cached address, and set the associating bit while holding the lock. The response handler takes the lock, rechecks the bit and the cached address, records the response, clears the bit, and only then completes the waiter. Thus cleanup cannot pass the handler between its state check and completion, and the cached 64-bit value cannot tear. The handler clears the bit before completing, not the woken waiter: otherwise complete() is issued under the lock and a second (e.g. malicious) response can reacquire it before the waiter and replace the result. So a wait that returns success implies the bit is already clear, and the success and negative-response paths return directly. The transmit-error and timeout paths still clear it under assoc_lock, which serializes any racing response against the cleanup while the call returns the error it already selected. Both paths snapshot assoc_status and assoc_addr under the same lock. Both users run in process context, so a plain spinlock is sufficient. The lock is not held while waiting for the completion. Suggested-by: Miquel Raynal <miquel.raynal@bootlin.com> Suggested-by: Xuanqiang Luo <xuanqiang.luo@linux.dev> Fixes: fefd19807fe9 ("mac802154: Handle associating") Cc: stable@vger.kernel.org Signed-off-by: Kaiwen Shi <skwkevin@mail.ustc.edu.cn> Reviewed-by: Xuanqiang Luo <luoxuanqiang@kylinos.cn> Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://patch.msgid.link/20260829230551.1787432-1-skwkevin@mail.ustc.edu.cn Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-05mac802154: fix netdev use-after-free in beacon workerZihan Xi
mac802154_beacon_worker() reads local->beacon_req under RCU and derives the sub-interface from the request, but then drops the RCU read lock and continues to use both sdata and the embedded wpan_dev. mac802154_stop_beacons_locked() cancels only pending beacon work, clears local->beacon_req and frees the request. A beacon worker that is already running can therefore continue after interface teardown and dereference the freed netdev private area. The scan worker already pins the netdev before leaving RCU. Apply the same lifetime rule to the beacon worker: take a netdev reference while the request is still protected by RCU, and release it on all paths that continue after the reference is acquired. Fixes: 3accf4762734 ("mac802154: Handle basic beaconing") Cc: stable@vger.kernel.org Reported-by: Vega <vega@nebusec.ai> Signed-off-by: Zihan Xi <zihanx@nebusec.ai> Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://patch.msgid.link/e9a3909c7a6281967961773ca841e860b8ecf40e.1785596603.git.zihanx@nebusec.ai Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-07-23mac802154: hold an interface reference across the scan workerIbrahim Hashimov
mac802154_scan_worker() captures the scanning sub-interface under RCU and then keeps dereferencing sdata->dev after rcu_read_unlock() and outside the rtnl -- in the failure traces, in mac802154_transmit_beacon_req() (skb->dev = sdata->dev), and in the end_scan cleanup. Nothing keeps that netdev alive across the worker iteration. A concurrent DEL_INTERFACE or PHY removal can unregister the interface once the worker drops the rtnl between its two drv_set_channel() sections. unregister_netdevice() frees the netdev asynchronously from netdev_run_todo() with the rtnl already dropped, so neither holding the rtnl nor the per-PHY IEEE802154_IS_SCANNING flag prevents a stale worker iteration from dereferencing the freed netdev -- a KASAN slab-use-after-free, reachable by racing TRIGGER_SCAN against DEL_INTERFACE (both CAP_NET_ADMIN). Pin the netdev with netdev_hold() while the RCU read lock is still held, and release it at every worker exit. Fixes: 57588c71177f ("mac802154: Handle passive scanning") Cc: stable@vger.kernel.org Signed-off-by: Ibrahim Hashimov <security@auditcode.ai> Link: https://patch.msgid.link/20260721211228.34578-1-security@auditcode.ai Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-19mac802154: Prevent overwrite return code in mac802154_perform_association()Robertus Diawan Chris
When assoc_status not equal to IEEE802154_ASSOCIATION_SUCCESSFUL, the return value assigned to either "-ERANGE" or "-EPERM" but this return value will be overwritten to 0 after exiting the conditional scope. So, jump to clear_assoc label to preserve the return value when assoc_status not equal to IEEE802154_ASSOCIATION_SUCCESSFUL. This is reported by Coverity Scan as "Unused value". Fixes: fefd19807fe9 ("mac802154: Handle associating") Signed-off-by: Robertus Diawan Chris <robertusdchris@gmail.com> Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/20260602054133.470293-1-robertusdchris@gmail.com Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
2026-02-21Convert 'alloc_obj' family to use the new default GFP_KERNEL argumentLinus Torvalds
This was done entirely with mindless brute force, using git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' | xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/' to convert the new alloc_obj() users that had a simple GFP_KERNEL argument to just drop that argument. Note that due to the extreme simplicity of the scripting, any slightly more complex cases spread over multiple lines would not be triggered: they definitely exist, but this covers the vast bulk of the cases, and the resulting diff is also then easier to check automatically. For the same reason the 'flex' versions will be done as a separate conversion. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook
This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2024-09-24mac802154: Fix potential RCU dereference issue in mac802154_scan_workerJiawei Ye
In the `mac802154_scan_worker` function, the `scan_req->type` field was accessed after the RCU read-side critical section was unlocked. According to RCU usage rules, this is illegal and can lead to unpredictable behavior, such as accessing memory that has been updated or causing use-after-free issues. This possible bug was identified using a static analysis tool developed by myself, specifically designed to detect RCU-related issues. To address this, the `scan_req->type` value is now stored in a local variable `scan_req_type` while still within the RCU read-side critical section. The `scan_req_type` is then used after the RCU lock is released, ensuring that the type value is safely accessed without violating RCU rules. Fixes: e2c3e6f53a7a ("mac802154: Handle active scanning") Cc: stable@vger.kernel.org Signed-off-by: Jiawei Ye <jiawei.ye@foxmail.com> Acked-by: Miquel Raynal <miquel.raynal@bootlin.com> Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com> Link: https://lore.kernel.org/tencent_3B2F4F2B4DA30FAE2F51A9634A16B3AD4908@qq.com Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
2023-12-15mac802154: Only allow PAN controllers to process association requestsMiquel Raynal
It is not very clear in the specification whether simple coordinators are allowed or not to answer to association requests themselves. As there is no synchronization mechanism, it is probably best to rely on the relay feature of these coordinators and avoid processing them in this case. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> Acked-by: Alexander Aring <aahringo@redhat.com> Link: https://lore.kernel.org/linux-wpan/20231128111655.507479-4-miquel.raynal@bootlin.com
2023-12-15mac80254: Provide real PAN coordinator info in beaconsMiquel Raynal
Sending a beacon is a way to advertise a PAN, but also ourselves as coordinator in the PAN. There is only one PAN coordinator in a PAN, this is the device without parent (not associated itself to an "upper" coordinator). Instead of blindly saying that we are the PAN coordinator, let's actually use our internal information to fill this field. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> Acked-by: Alexander Aring <aahringo@redhat.com> Link: https://lore.kernel.org/linux-wpan/20231128111655.507479-2-miquel.raynal@bootlin.com
2023-11-20mac802154: Handle disassociation notifications from peersMiquel Raynal
Peers may decided to disassociate from us, their coordinator, in this case they will send a disassociation notification which we must acknowledge. If we don't, the peer device considers itself disassociated anyway. We also need to drop the reference to this child from our internal structures. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> Acked-by: Alexander Aring <aahringo@redhat.com> Link: https://lore.kernel.org/linux-wpan/20230927181214.129346-11-miquel.raynal@bootlin.com
2023-11-20mac802154: Follow the number of associated devicesMiquel Raynal
Track the count of associated devices. Limit the number of associations using the value provided by the user if any. If we reach the maximum number of associations, we tell the device we are at capacity. If the user do not want to accept any more associations, it may specify the value 0 to the maximum number of associations, which will lead to an access denied error status returned to the peers trying to associate. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> Acked-by: Alexander Aring <aahringo@redhat.com> Link: https://lore.kernel.org/linux-wpan/20230927181214.129346-10-miquel.raynal@bootlin.com
2023-11-20mac802154: Handle association requests from peersMiquel Raynal
Coordinators may have to handle association requests from peers which want to join the PAN. The logic involves: - Acknowledging the request (done by hardware) - If requested, a random short address that is free on this PAN should be chosen for the device. - Sending an association response with the short address allocated for the peer and expecting it to be ack'ed. If anything fails during this procedure, the peer is considered not associated. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> Acked-by: Alexander Aring <aahringo@redhat.com> Link: https://lore.kernel.org/linux-wpan/20230927181214.129346-8-miquel.raynal@bootlin.com
2023-11-20mac802154: Handle disassociationsMiquel Raynal
Devices may decide to disassociate from their coordinator for different reasons (device turning off, coordinator signal strength too low, etc), the MAC layer just has to send a disassociation notification. If the ack of the disassociation notification is not received, the device may consider itself disassociated anyway. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> Acked-by: Alexander Aring <aahringo@redhat.com> Link: https://lore.kernel.org/linux-wpan/20230927181214.129346-7-miquel.raynal@bootlin.com
2023-11-20mac802154: Handle associatingMiquel Raynal
Joining a PAN officially goes by associating with a coordinator. This coordinator may have been discovered thanks to the beacons it sent in the past. Add support to the MAC layer for these associations, which require: - Sending an association request - Receiving an association response The association response contains the association status, eventually a reason if the association was unsuccessful, and finally a short address that we should use for intra-PAN communication from now on, if we required one (which is the default, and not yet configurable). Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> Acked-by: Alexander Aring <aahringo@redhat.com> Link: https://lore.kernel.org/linux-wpan/20230927181214.129346-5-miquel.raynal@bootlin.com
2023-06-06Merge tag 'v6.4-rc4' into wpan-next/stagingMiquel Raynal
Linux 6.4-rc4
2023-04-05mac802154: Rename kfree_rcu() to kvfree_rcu_mightsleep()Joel Fernandes (Google)
The k[v]free_rcu() macro's single-argument form is deprecated. Therefore switch to the new k[v]free_rcu_mightsleep() variant. The goal is to avoid accidental use of the single-argument forms, which can introduce functionality bugs in atomic contexts and latency bugs in non-atomic contexts. The callers are holding a mutex so the context allows blocking. Hence using the API with a single argument will be fine, but use its new name. There is no functionality change with this patch. Fixes: 57588c71177f ("mac802154: Handle passive scanning") Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
2023-03-23mac802154: Handle received BEACON_REQMiquel Raynal
When performing an active scan, devices emit BEACON_REQ which must be answered by other PANs receiving the request, unless they are already passively sending beacons. Answering a beacon request becomes a duty when the user tells us to send beacons and the request provides an interval of 15. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Acked-by: Alexander Aring <aahringo@redhat.com> Link: https://lore.kernel.org/r/20230310145346.1397068-5-miquel.raynal@bootlin.com Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
2023-03-23mac802154: Handle active scanningMiquel Raynal
Active scan support is based on the current passive scan support, cheered up with beacon requests sent after every channel change. Co-developed-by: David Girault <david.girault@qorvo.com> Signed-off-by: David Girault <david.girault@qorvo.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Acked-by: Alexander Aring <aahringo@redhat.com> Link: https://lore.kernel.org/r/20230310145346.1397068-3-miquel.raynal@bootlin.com Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
2023-02-18mac802154: Fix an always true conditionMiquel Raynal
At this stage we simply do not care about the delayed work value, because active scan is not yet supported, so we can blindly queue another work once a beacon has been sent. It fixes a smatch warning: mac802154_beacon_worker() warn: always true condition '(local->beacon_interval >= 0) => (0-u32max >= 0)' Fixes: 3accf4762734 ("mac802154: Handle basic beaconing") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/r/20230214135035.1202471-6-miquel.raynal@bootlin.com Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
2023-02-18mac802154: Send beacons using the MLME Tx pathMiquel Raynal
Using ieee802154_subif_start_xmit() to bypass the net queue when sending beacons is broken because it does not acquire the HARD_TX_LOCK(), hence not preventing datagram buffers to be smashed by beacons upon contention situation. Using the mlme_tx helper is not the best fit either but at least it is not buggy and has little-to-no performance hit. More details are given in the comment explaining this choice in the code. Fixes: 3accf4762734 ("mac802154: Handle basic beaconing") Reported-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/r/20230214135035.1202471-5-miquel.raynal@bootlin.com Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
2023-01-30mac802154: Avoid superfluous endianness handlingMiquel Raynal
When compiling scan.c with C=1, Sparse complains with: sparse: expected unsigned short [usertype] val sparse: got restricted __le16 [usertype] pan_id sparse: sparse: cast from restricted __le16 sparse: expected unsigned long long [usertype] val sparse: got restricted __le64 [usertype] extended_addr sparse: sparse: cast from restricted __le64 The tool is right, both pan_id and extended_addr already are rightfully defined as being __le16 and __le64 on both sides of the operations and do not require extra endianness handling. Fixes: 3accf4762734 ("mac802154: Handle basic beaconing") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/r/20230130154306.114265-1-miquel.raynal@bootlin.com Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
2023-01-28mac802154: Handle basic beaconingMiquel Raynal
Implement the core hooks in order to provide the softMAC layer support for sending beacons. Coordinators may be requested to send beacons in a beacon enabled PAN in order for the other devices around to self discover the available PANs automatically. Changing the channels is prohibited while a beacon operation is ongoing. The implementation uses a workqueue triggered at a certain interval depending on the symbol duration for the current channel and the interval order provided. Sending beacons in response to a BEACON_REQ frame (ie. answering active scans) is not yet supported. This initial patchset has no security support (llsec). Co-developed-by: David Girault <david.girault@qorvo.com> Signed-off-by: David Girault <david.girault@qorvo.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Acked-by: Alexander Aring <aahringo@redhat.com> Link: https://lore.kernel.org/r/20230125102923.135465-3-miquel.raynal@bootlin.com Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
2023-01-03mac802154: Handle passive scanningMiquel Raynal
Implement the core hooks in order to provide the softMAC layer support for passive scans. Scans are requested by the user and can be aborted. Changing channels manually is prohibited during scans. The implementation uses a workqueue triggered at a certain interval depending on the symbol duration for the current channel and the duration order provided. More advanced drivers with internal scheduling capabilities might require additional care but there is none mainline yet. Received beacons during a passive scan are processed in a work queue and their result forwarded to the upper layer. Active scanning is not supported yet. Co-developed-by: David Girault <david.girault@qorvo.com> Signed-off-by: David Girault <david.girault@qorvo.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Acked-by: Alexander Aring <aahringo@redhat.com> Link: https://lore.kernel.org/r/20230103165644.432209-7-miquel.raynal@bootlin.com Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>