kernel/linux.git/net/mac80211, branch v6.19.11

wifi: mac80211: always free skb on ieee80211_tx_prepare_skb() failure

2026-03-25T10:13:28+00:00

[ Upstream commit d5ad6ab61cbd89afdb60881f6274f74328af3ee9 ] ieee80211_tx_prepare_skb() has three error paths, but only two of them free the skb. The first error path (ieee80211_tx_prepare() returning TX_DROP) does not free it, while invoke_tx_handlers() failure and the fragmentation check both do. Add kfree_skb() to the first error path so all three are consistent, and remove the now-redundant frees in callers (ath9k, mt76, mac80211_hwsim) to avoid double-free. Document the skb ownership guarantee in the function's kdoc. Signed-off-by: Felix Fietkau Link: https://patch.msgid.link/20260314065455.2462900-1-nbd@nbd.name Fixes: 06be6b149f7e ("mac80211: add ieee80211_tx_prepare_skb() helper function") Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: mac80211: fix NULL deref in mesh_matches_local()

2026-03-25T10:13:27+00:00

[ Upstream commit c73bb9a2d33bf81f6eecaa0f474b6c6dbe9855bd ] mesh_matches_local() unconditionally dereferences ie->mesh_config to compare mesh configuration parameters. When called from mesh_rx_csa_frame(), the parsed action-frame elements may not contain a Mesh Configuration IE, leaving ie->mesh_config NULL and triggering a kernel NULL pointer dereference. The other two callers are already safe: - ieee80211_mesh_rx_bcn_presp() checks !elems->mesh_config before calling mesh_matches_local() - mesh_plink_get_event() is only reached through mesh_process_plink_frame(), which checks !elems->mesh_config, too mesh_rx_csa_frame() is the only caller that passes raw parsed elements to mesh_matches_local() without guarding mesh_config. An adjacent attacker can exploit this by sending a crafted CSA action frame that includes a valid Mesh ID IE but omits the Mesh Configuration IE, crashing the kernel. The captured crash log: Oops: general protection fault, probably for non-canonical address ... KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] Workqueue: events_unbound cfg80211_wiphy_work [...] Call Trace: ? __pfx_mesh_matches_local (net/mac80211/mesh.c:65) ieee80211_mesh_rx_queued_mgmt (net/mac80211/mesh.c:1686) [...] ieee80211_iface_work (net/mac80211/iface.c:1754 net/mac80211/iface.c:1802) [...] cfg80211_wiphy_work (net/wireless/core.c:426) process_one_work (net/kernel/workqueue.c:3280) ? assign_work (net/kernel/workqueue.c:1219) worker_thread (net/kernel/workqueue.c:3352) ? __pfx_worker_thread (net/kernel/workqueue.c:3385) kthread (net/kernel/kthread.c:436) [...] ret_from_fork_asm (net/arch/x86/entry/entry_64.S:255) This patch adds a NULL check for ie->mesh_config at the top of mesh_matches_local() to return false early when the Mesh Configuration IE is absent. Fixes: 2e3c8736820b ("mac80211: support functions for mesh") Reported-by: Weiming Shi Signed-off-by: Xiang Mei Link: https://patch.msgid.link/20260318034244.2595020-1-xmei5@asu.edu Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: mac80211: Fix static_branch_dec() underflow for aql_disable.

2026-03-25T10:13:23+00:00

[ Upstream commit b94ae8e0d5fe1bdbbfdc3854ff6ce98f6876a828 ] syzbot reported static_branch_dec() underflow in aql_enable_write(). [0] The problem is that aql_enable_write() does not serialise concurrent write()s to the debugfs. aql_enable_write() checks static_key_false(&aql_disable.key) and later calls static_branch_inc() or static_branch_dec(), but the state may change between the two calls. aql_disable does not need to track inc/dec. Let's use static_branch_enable() and static_branch_disable(). [0]: val == 0 WARNING: kernel/jump_label.c:311 at __static_key_slow_dec_cpuslocked.part.0+0x107/0x120 kernel/jump_label.c:311, CPU#0: syz.1.3155/20288 Modules linked in: CPU: 0 UID: 0 PID: 20288 Comm: syz.1.3155 Tainted: G U L syzkaller #0 PREEMPT(full) Tainted: [U]=USER, [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:__static_key_slow_dec_cpuslocked.part.0+0x107/0x120 kernel/jump_label.c:311 Code: f2 c9 ff 5b 5d c3 cc cc cc cc e8 54 f2 c9 ff 48 89 df e8 ac f9 ff ff eb ad e8 45 f2 c9 ff 90 0f 0b 90 eb a2 e8 3a f2 c9 ff 90 <0f> 0b 90 eb 97 48 89 df e8 5c 4b 33 00 e9 36 ff ff ff 0f 1f 80 00 RSP: 0018:ffffc9000b9f7c10 EFLAGS: 00010293 RAX: 0000000000000000 RBX: ffffffff9b3e5d40 RCX: ffffffff823c57b4 RDX: ffff8880285a0000 RSI: ffffffff823c5846 RDI: ffff8880285a0000 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 000000000000000a R13: 1ffff9200173ef88 R14: 0000000000000001 R15: ffffc9000b9f7e98 FS: 00007f530dd726c0(0000) GS:ffff8881245e3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000001140 CR3: 000000007cc4a000 CR4: 00000000003526f0 Call Trace: __static_key_slow_dec_cpuslocked kernel/jump_label.c:297 [inline] __static_key_slow_dec kernel/jump_label.c:321 [inline] static_key_slow_dec+0x7c/0xc0 kernel/jump_label.c:336 aql_enable_write+0x2b2/0x310 net/mac80211/debugfs.c:343 short_proxy_write+0x133/0x1a0 fs/debugfs/file.c:383 vfs_write+0x2aa/0x1070 fs/read_write.c:684 ksys_pwrite64 fs/read_write.c:793 [inline] __do_sys_pwrite64 fs/read_write.c:801 [inline] __se_sys_pwrite64 fs/read_write.c:798 [inline] __x64_sys_pwrite64+0x1eb/0x250 fs/read_write.c:798 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f530cf9aeb9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f530dd72028 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007f530d215fa0 RCX: 00007f530cf9aeb9 RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000010 RBP: 00007f530d008c1f R08: 0000000000000000 R09: 0000000000000000 R10: 4200000000000005 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f530d216038 R14: 00007f530d215fa0 R15: 00007ffde89fb978 Fixes: e908435e402a ("mac80211: introduce aql_enable node in debugfs") Reported-by: syzbot+feb9ce36a95341bb47a4@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/69a8979e.a70a0220.b118c.0025.GAE@google.com/ Signed-off-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260306072405.3649474-1-kuniyu@google.com Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: mac80211: use jiffies_delta_to_msecs() for sta_info inactive times

2026-03-25T10:13:23+00:00

[ Upstream commit ac6f24cc9c0a9aefa55ec9696dcafa971d4d760b ] Inactive times of around 0xffffffff milliseconds have been observed on an ath9k device on ARM. This is likely due to a memory ordering race in the jiffies_to_msecs(jiffies - last_active()) calculation causing an overflow when the observed jiffies is below ieee80211_sta_last_active(). Use jiffies_delta_to_msecs() instead to avoid this problem. Fixes: 7bbdd2d98797 ("mac80211: implement station stats retrieval") Signed-off-by: Nicolas Cavallari Link: https://patch.msgid.link/20260303161701.31808-1-nicolas.cavallari@green-communications.fr Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: mac80211: remove keys after disabling beaconing

2026-03-25T10:13:23+00:00

[ Upstream commit 708bbb45537780a8d3721ca1e0cf1932c1d1bf5f ] We shouldn't remove keys before disable beaconing, at least when beacon protection is used, since that would remove keys that are still used for beacon transmission at the same time. Stop before removing keys so there's no race. Fixes: af2d14b01c32 ("mac80211: Beacon protection using the new BIGTK (STA)") Reviewed-by: Miriam Rachel Korenblit Link: https://patch.msgid.link/20260303150339.574e7887b3ab.I50d708f5aa22584506a91d0da7f8a73ba39fceac@changeid Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

mac80211: fix crash in ieee80211_chan_bw_change for AP_VLAN stations

2026-03-25T10:13:16+00:00

commit 672e5229e1ecfc2a3509b53adcb914d8b024a853 upstream. ieee80211_chan_bw_change() iterates all stations and accesses link->reserved.oper via sta->sdata->link[link_id]. For stations on AP_VLAN interfaces (e.g. 4addr WDS clients), sta->sdata points to the VLAN sdata, whose link never participates in chanctx reservations. This leaves link->reserved.oper zero-initialized with chan == NULL, causing a NULL pointer dereference in __ieee80211_sta_cap_rx_bw() when accessing chandef->chan->band during CSA. Resolve the VLAN sdata to its parent AP sdata using get_bss_sdata() before accessing link data. Cc: stable@vger.kernel.org Signed-off-by: Felix Fietkau Link: https://patch.msgid.link/20260305170812.2904208-1-nbd@nbd.name [also change sta->sdata in ARRAY_SIZE even if it doesn't matter] Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman

wifi: mac80211: set default WMM parameters on all links

2026-03-19T15:14:46+00:00

[ Upstream commit 2259d14499d16b115ef8d5d2ddc867e2be7cb5b5 ] Currently, mac80211 only initializes default WMM parameters on the deflink during do_open(). For MLO cases, this leaves the additional links without proper WMM defaults if hostapd does not supply per-link WMM parameters, leading to inconsistent QoS behavior across links. Set default WMM parameters for each link during ieee80211_vif_update_links(), because this ensures all individual links in an MLD have valid WMM settings during bring-up and behave consistently across different BSS. Signed-off-by: Ramanathan Choodamani Signed-off-by: Aishwarya R Link: https://patch.msgid.link/20260205094216.3093542-1-aishwarya.r@oss.qualcomm.com Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: mac80211: fix NULL pointer dereference in mesh_rx_csa_frame()

2026-03-12T11:09:34+00:00

commit 017c1792525064a723971f0216e6ef86a8c7af11 upstream. In mesh_rx_csa_frame(), elems->mesh_chansw_params_ie is dereferenced at lines 1638 and 1642 without a prior NULL check: ifmsh->chsw_ttl = elems->mesh_chansw_params_ie->mesh_ttl; ... pre_value = le16_to_cpu(elems->mesh_chansw_params_ie->mesh_pre_value); The mesh_matches_local() check above only validates the Mesh ID, Mesh Configuration, and Supported Rates IEs. It does not verify the presence of the Mesh Channel Switch Parameters IE (element ID 118). When a received CSA action frame omits that IE, ieee802_11_parse_elems() leaves elems->mesh_chansw_params_ie as NULL, and the unconditional dereference causes a kernel NULL pointer dereference. A remote mesh peer with an established peer link (PLINK_ESTAB) can trigger this by sending a crafted SPECTRUM_MGMT/CHL_SWITCH action frame that includes a matching Mesh ID and Mesh Configuration IE but omits the Mesh Channel Switch Parameters IE. No authentication beyond the default open mesh peering is required. Crash confirmed on kernel 6.17.0-5-generic via mac80211_hwsim: BUG: kernel NULL pointer dereference, address: 0000000000000000 Oops: Oops: 0000 [#1] SMP NOPTI RIP: 0010:ieee80211_mesh_rx_queued_mgmt+0x143/0x2a0 [mac80211] CR2: 0000000000000000 Fix by adding a NULL check for mesh_chansw_params_ie after mesh_matches_local() returns, consistent with how other optional IEs are guarded throughout the mesh code. The bug has been present since v3.13 (released 2014-01-19). Fixes: 8f2535b92d68 ("mac80211: process the CSA frame for mesh accordingly") Cc: stable@vger.kernel.org Signed-off-by: Vahagn Vardanian Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman

wifi: mac80211: bounds-check link_id in ieee80211_ml_reconfiguration

2026-03-12T11:09:34+00:00

commit 162d331d833dc73a3e905a24c44dd33732af1fc5 upstream. link_id is taken from the ML Reconfiguration element (control & 0x000f), so it can be 0..15. link_removal_timeout[] has IEEE80211_MLD_MAX_NUM_LINKS (15) elements, so index 15 is out-of-bounds. Skip subelements with link_id >= IEEE80211_MLD_MAX_NUM_LINKS to avoid a stack out-of-bounds write. Fixes: 8eb8dd2ffbbb ("wifi: mac80211: Support link removal using Reconfiguration ML element") Reported-by: Ariel Silver Signed-off-by: Ariel Silver Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260220101129.1202657-1-Ariel.Silver@cybereason.com Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman

wifi: mac80211: correctly decode TTLM with default link map

2026-01-29T10:46:43+00:00

TID-To-Link Mapping (TTLM) elements do not contain any link mapping presence indicator if a default mapping is used and parsing needs to be skipped. Note that access points should not explicitly report an advertised TTLM with a default mapping as that is the implied mapping if the element is not included, this is even the case when switching back to the default mapping. However, mac80211 would incorrectly parse the frame and would also read one byte beyond the end of the element. Reported-by: Ruikai Peng Closes: https://lore.kernel.org/linux-wireless/CAFD3drMqc9YWvTCSHLyP89AOpBZsHdZ+pak6zVftYoZcUyF7gw@mail.gmail.com Fixes: 702e80470a33 ("wifi: mac80211: support handling of advertised TID-to-link mapping") Signed-off-by: Benjamin Berg Link: https://patch.msgid.link/20260129113349.d6b96f12c732.I69212a50f0f70db185edd3abefb6f04d3cb3e5ff@changeid Signed-off-by: Johannes Berg