kernel/linux.git/net/mac80211, branch v6.18.44

wifi: mac80211: validate individual TWT params before driver setup

2026-08-09T18:25:05+00:00

[ Upstream commit 0502d5077e419427d80f4d46ba95d0067f5fb916 ] ieee80211_process_rx_twt_action() only partially validates a received S1G TWT setup frame before queueing it. An individual agreement can therefore reach ieee80211_s1g_rx_twt_setup() with twt->length too short for the full struct ieee80211_twt_params. The individual path passes twt to drv_add_twt_setup(). Both the tracepoint and the driver callback consume the complete parameters block, not merely req_type. Do not pass a short individual agreement to the driver. Broadcast agreements remain unchanged because they are rejected locally after accessing only req_type. Fixes: f5a4c24e689f ("mac80211: introduce individual TWT support in AP mode") Assisted-by: Codex:gpt-5 Assisted-by: Claude:opus-4.8 Signed-off-by: Zhao Li Link: https://patch.msgid.link/20260723010928.76551-1-enderaoelyther@gmail.com [edit commit message to not overclaim lack of validation nor understate driver impact] Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: mac80211: recalculate TIM when a station enters power save

2026-08-03T09:21:41+00:00

[ Upstream commit a007a384c9eb17610f53a53e2f59944c31f1565a ] When an AP buffers frames for a station on its per-station TXQs and the station subsequently enters power save, sta_ps_start() records the buffered TIDs in txq_buffered_tids but does not update the TIM. The station's TIM bit is only ever set when a further frame is buffered while the station is already asleep (ieee80211_tx_h_unicast_ps_buf() -> sta_info_recalc_tim()). If no further downlink frame arrives for that station the beacon TIM never advertises the buffered traffic. A station relying on the TIM then remains in doze indefinitely on top of a non-empty queue. Its TXQs were removed from the scheduler's active list at PS entry, nothing pages it, and the flow deadlocks until an unrelated event wakes the station. Recalculate the TIM at the end of sta_ps_start(), so traffic already buffered at PS entry is advertised immediately. sta_info_recalc_tim() already consults txq_buffered_tids, which is updated above, and is safe in this context (it is already called from equivalent paths such as the tx handlers and ieee80211_handle_filtered_frame()). Fixes: ba8c3d6f16a1 ("mac80211: add an intermediate software queue implementation") Signed-off-by: Andrew Pope Link: https://patch.msgid.link/20260717011751.79524-1-andrew.pope@morsemicro.com [add wifi: subject prefix] Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: mac80211: tear down new links on vif update error path

2026-08-03T09:21:41+00:00

[ Upstream commit 952c02b33f56207a160421bcd61e7ac53c9c59ae ] When ieee80211_vif_update_links() adds new links it allocates a link container for each and calls ieee80211_link_init() (which registers the per-link debugfs files with file->private_data pointing into the container) and ieee80211_link_setup(). If the subsequent drv_change_vif_links() fails, the error path restores the old pointers and jumps to 'free', which frees the new containers but never removes their debugfs entries or stops the links. The debugfs files survive with file->private_data dangling at the freed container, so a later open()+read() (e.g. link-1/txpower) dereferences freed memory in ieee80211_if_read_link(), a use-after-free. The removal path already dismantles links correctly via ieee80211_tear_down_links(), which removes each link's keys and debugfs entries and calls ieee80211_link_stop(); the add path on the error branch does not. Commit be1ba9ed221f ("wifi: mac80211: avoid weird state in error path") hardened this same error path for the link-removal case (new_links == 0) but left the newly-added links' teardown unaddressed. drv_change_vif_links() can fail at runtime on MLO drivers (internal allocation / queue / firmware command failures). Remove the new links' debugfs entries and stop them before freeing. BUG: KASAN: slab-use-after-free in ieee80211_if_read_link (net/mac80211/debugfs_netdev.c:127) Read of size 8 at addr ffff888011290000 by task exploit/145 Call Trace: ... ieee80211_if_read_link (net/mac80211/debugfs_netdev.c:127) short_proxy_read (fs/debugfs/file.c:373) vfs_read (fs/read_write.c:572) ksys_read (fs/read_write.c:716) do_syscall_64 (arch/x86/entry/syscall_64.c:94) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121) ... Oops: general protection fault, probably for non-canonical address 0xdffffc000000000a RIP: 0010:ieee80211_if_read_link (net/mac80211/debugfs_netdev.c:127) Kernel panic - not syncing: Fatal exception Fixes: 170cd6a66d9a ("wifi: mac80211: add netdev per-link debugfs data and driver hook") Reported-by: Weiming Shi Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Xiang Mei Link: https://patch.msgid.link/20260711210302.2098404-1-xmei5@asu.edu Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: mac80211: free AP_VLAN bc_buf SKBs outside IRQ lock

2026-08-03T09:21:31+00:00

[ Upstream commit f3858d5b1432098c1936e03d6e03dd0e33facf60 ] ieee80211_do_stop() removes AP_VLAN packets from the parent AP ps->bc_buf while holding ps->bc_buf.lock with IRQs disabled. It then calls ieee80211_free_txskb() before dropping the lock. ieee80211_free_txskb() is not just a passive SKB release. For SKBs with TX status state it can report a dropped frame through cfg80211/nl80211, and that path can reach netlink tap transmit. This is the same reason the pending queue cleanup in ieee80211_do_stop() already unlinks SKBs under the queue lock and frees them after IRQ state is restored. The buggy scenario involves two paths, with each column showing the order within that path: AP_VLAN management TX: AP_VLAN stop: 1. attach ACK-status state 1. clear the running state 2. queue a multicast SKB on 2. take ps->bc_buf.lock with IRQs parent ps->bc_buf disabled 3. unlink the AP_VLAN SKB 4. call ieee80211_free_txskb() Unlink matching AP_VLAN SKBs from ps->bc_buf under the existing lock, but move them to a local free queue. Drop the lock and restore IRQ state before calling ieee80211_free_txskb(). WARNING: kernel/softirq.c:430 at __local_bh_enable_ip Fixes: 397a7a24ef8c ("mac80211: free ps->bc_buf skbs on vlan device stop") Assisted-by: Codex:gpt-5.5 Signed-off-by: Cen Zhang Link: https://patch.msgid.link/20260706140841.581566-1-zzzccc427@gmail.com Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: mac80211: avoid non-S1G AID fallback for S1G assoc

2026-08-03T09:21:31+00:00

[ Upstream commit 035ed430ce6a2c35b01e211844a9f0a7643e57a4 ] When assoc_data->s1g is set and no AID Response element is present, falling back to mgmt->u.assoc_resp.aid reads the non-S1G association-response layout. Keep the fallback for non-S1G only. If a successful S1G association response omits the AID Response element, abandon the association instead of proceeding with AID 0. Initialize aid to 0 for other S1G responses so the later mask and logging flow keeps a defined value without reading the non-S1G layout. Fixes: 2a8a6b7c4cb0 ("wifi: mac80211: handle station association response with S1G") Assisted-by: Codex:gpt-5.5 Assisted-by: Claude:claude-opus-4.8 Signed-off-by: Zhao Li Link: https://patch.msgid.link/20260612152440.25955-2-enderaoelyther@gmail.com Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: mac80211: defer link RX stats percpu free to RCU

2026-08-03T09:21:30+00:00

[ Upstream commit aa2eb62525188269cdd402a583b9a8ed94657ff0 ] sta_remove_link() frees a removed MLO link's RX stats percpu buffer right away, but defers only the link container to RCU: sta_info_free_link(&alloc->info); kfree_rcu(alloc, rcu_head); The RX fast path reads link_sta under rcu_read_lock and writes the percpu stats. A reader that resolved link_sta before the removal keeps the pointer. The container stays alive from the kfree_rcu, so the read still works. But the percpu block it points to is already freed. This needs uses_rss. That is when pcpu_rx_stats exists. The full STA teardown frees the deflink stats only after synchronize_net(). The link removal path had no such barrier. The race is hard to win in practice, but the free should still wait for RCU. Free the link together with its data from a single RCU callback, so the percpu block is reclaimed only after readers drain. Fixes: c71420db653a ("wifi: mac80211: RCU-ify link STA pointers") Link: https://lore.kernel.org/r/20260626080158.3589711-1-maoyixie.tju@gmail.com Suggested-by: Johannes Berg Co-developed-by: Kaixuan Li Signed-off-by: Kaixuan Li Signed-off-by: Maoyi Xie Link: https://patch.msgid.link/20260627083028.3826810-1-maoyixie.tju@gmail.com Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: mac80211: fix fils_discovery double free on alloc failure

2026-08-03T09:21:30+00:00

[ Upstream commit 286e52a799fa158bdbd77da1426c4d93f9a6e7ad ] ieee80211_set_fils_discovery() calls kfree_rcu() on the old template before allocating the replacement. If the kzalloc() then fails, it returns -ENOMEM while link->u.ap.fils_discovery still points at the object already queued for freeing. A later update or AP teardown (ieee80211_stop_ap()) re-queues that same rcu_head; the second free is caught by KASAN when the RCU sheaf is processed in softirq: BUG: KASAN: double-free in rcu_free_sheaf (mm/slub.c:5850) Free of addr ffff88800c065280 by task swapper/0/0 ... __rcu_free_sheaf_prepare (mm/slub.c:2634 mm/slub.c:2940) rcu_free_sheaf (mm/slub.c:5850) rcu_core (kernel/rcu/tree.c:2617 kernel/rcu/tree.c:2869) handle_softirqs (kernel/softirq.c:622) The buggy address belongs to the cache kmalloc-96 of size 96 Queue the old object for kfree_rcu() only after the new one is published, matching ieee80211_set_probe_resp() and ieee80211_set_s1g_short_beacon(). Fixes: 3b1c256eb4ae ("wifi: mac80211: fixes in FILS discovery updates") Reported-by: Weiming Shi Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Xiang Mei Link: https://patch.msgid.link/20260621093532.884188-2-xmei5@asu.edu Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: mac80211: fix unsol_bcast_probe_resp double free on alloc failure

2026-08-03T09:21:30+00:00

[ Upstream commit 1d067abcd37062426c59ec73dbc4e87a63f33fea ] ieee80211_set_unsol_bcast_probe_resp() calls kfree_rcu() on the old template before allocating the replacement. If the kzalloc() then fails, it returns -ENOMEM while link->u.ap.unsol_bcast_probe_resp still points at the object already queued for freeing. A later update or AP teardown re-queues that same rcu_head; the second free is caught by KASAN when the RCU sheaf is processed in softirq: BUG: KASAN: double-free in rcu_free_sheaf (mm/slub.c:5850) Free of addr ffff88800d06f300 by task exploit/145 ... __rcu_free_sheaf_prepare (mm/slub.c:2634 mm/slub.c:2940) rcu_free_sheaf (mm/slub.c:5850) rcu_core (kernel/rcu/tree.c:2617 kernel/rcu/tree.c:2869) handle_softirqs (kernel/softirq.c:622) The buggy address belongs to the cache kmalloc-128 of size 128 Queue the old object for kfree_rcu() only after the new one is published, matching ieee80211_set_probe_resp() and ieee80211_set_s1g_short_beacon(). Fixes: 3b1c256eb4ae ("wifi: mac80211: fixes in FILS discovery updates") Reported-by: Weiming Shi Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Xiang Mei Link: https://patch.msgid.link/20260621093532.884188-1-xmei5@asu.edu Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: mac80211: free ack status frame on TX header build failure

2026-07-24T14:17:18+00:00

commit 2c51457d930f723e5f2903af90f5847f7df53f42 upstream. ieee80211_build_hdr() stores an ACK status frame before it has finished all validation and header construction. If a later error path is taken, the transmit skb is freed but the stored ACK status frame remains in local->ack_status_frames. This can happen for control port frames when the requested MLO link ID does not match the link selected for a non-MLO station. Repeated failures can fill the ACK status IDR and leave pending ACK frames until hardware teardown. Remove any stored ACK status frame before returning an error after it has been inserted into the IDR. Fixes: a729cff8ad51 ("mac80211: implement wifi TX status") Cc: stable@vger.kernel.org Reported-by: Yuan Tan Reported-by: Yifan Wu Reported-by: Juefei Pu Reported-by: Xin Liu Assisted-by: Codex:gpt-5.4 Signed-off-by: Zhiling Zou Signed-off-by: Ren Wei Link: https://patch.msgid.link/9de0423da840e92084915b8f92e66a421245c4b8.1782462409.git.roxy520tt@gmail.com Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman

wifi: mac80211: fix memory leak in ieee80211_register_hw()

2026-07-24T14:17:17+00:00

commit 95fc02722edde02946d0d475221f2b2054d3d8ba upstream. If kmemdup() fails while copying supported band structures, the error path jumps to fail_rate. This skips rate_control_deinitialize() and leaks the initialized local->rate_ctrl. Fix this by adding a fail_band label that shares the rate-control cleanup path before falling through to the remaining teardown. The bug was first flagged by an experimental analysis tool we are developing for kernel memory-management bugs while analyzing v6.13-rc1. The tool is still under development and is not yet publicly available. Manual inspection confirms that the bug is still present in v7.1-rc7. An x86_64 allyesconfig build showed no new warnings. As we do not have a suitable mac80211 device/driver combination to test with, no runtime testing was able to be performed. Fixes: 09b4a4faf9d0 ("mac80211: introduce capability flags for VHT EXT NSS support") Cc: stable@vger.kernel.org Reviewed-by: Zilin Guan Signed-off-by: Dawei Feng Link: https://patch.msgid.link/20260706143507.146131-1-dawei.feng@seu.edu.cn Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman