kernel/linux.git/net/wireless/scan.c, branch v6.12.102

wifi: cfg80211: bound element ID read when checking non-inheritance

2026-08-03T09:17:03+00:00

[ Upstream commit cb8afea4655ff004fa7feee825d5c79783525383 ] cfg80211_is_element_inherited() reads the first data octet of the candidate element (id = elem->data[0]) to look it up in an extension non-inheritance list. It does so after testing elem->id, but without verifying that the element actually has a data octet. A zero-length extension element (WLAN_EID_EXTENSION with length 0) therefore makes it read one octet past the end of the element. _ieee802_11_parse_elems_full() runs this check for every element of a frame once a non-inheritance context exists -- e.g. while parsing a per-STA profile of a Multi-Link element in a (re)association response, or a non-transmitted BSS profile -- so a crafted frame from an AP can trigger a one-octet slab-out-of-bounds read during element parsing: BUG: KASAN: slab-out-of-bounds in cfg80211_is_element_inherited Read of size 1 ... in net/wireless/scan.c Return early (treat the element as inherited) when an extension element carries no data, mirroring the existing handling of empty ID lists. The bug was found by fuzzing ieee802_11_parse_elems_full() under KASAN. Fixes: f7dacfb11475 ("cfg80211: support non-inheritance element") Signed-off-by: HE WEI (ギカク) Link: https://patch.msgid.link/20260707094828.16465-1-skyexpoc@gmail.com Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: cfg80211: derive S1G beacon TSF from S1G fields

2026-08-03T09:17:02+00:00

[ Upstream commit 4e5a4641e7b4763656336b7891d01359aaf363cd ] cfg80211_inform_bss_frame_data() parses S1G beacons with the extension frame layout, but still reads the TSF from the regular probe response layout after the S1G branch. For S1G beacons that reads bytes at the regular management-frame timestamp offset instead of the S1G timestamp. Use the 32-bit S1G beacon timestamp and the S1G Beacon Compatibility element's TSF completion field when informing an S1G BSS. Keep the regular management-frame timestamp read in the non-S1G branch. Fixes: 9eaffe5078ca ("cfg80211: convert S1G beacon to scan results") Signed-off-by: Zhao Li Tested-by: Lachlan Hodges Reviewed-by: Lachlan Hodges Link: https://patch.msgid.link/20260611161943.91069-6-enderaoelyther@gmail.com Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: cfg80211: define and use wiphy guard

2026-08-03T09:17:02+00:00

[ Upstream commit f42d22d3f79639c1b4e41daf28dad2505d6a5a8b ] Define a guard for the wiphy mutex, and use it in most code in cfg80211, though not all due to some interaction with RTNL and/or indentation. Suggested-by: Jeff Johnson Reviewed-by: Jeff Johnson Signed-off-by: Johannes Berg Link: https://patch.msgid.link/20241122094225.88765cbaab65.I610c9b14f36902e75e1d13f0db29f8bef2298804@changeid Signed-off-by: Johannes Berg Stable-dep-of: 2b0eab425e1f ("wifi: cfg80211: convert pmsr_free_wk to wiphy_work to fix deadlock") Signed-off-by: Sasha Levin

wifi: cfg80211: advance loop vars in cfg80211_merge_profile()

2026-06-01T15:46:20+00:00

commit 7666dbb1bacc4ba522b96740cba7283d243d16e1 upstream. cfg80211_merge_profile() reassembles a Multi-BSSID non-transmitted BSS profile that has been split across multiple consecutive MBSSID elements. Its while-loop calls cfg80211_get_profile_continuation(ie, ielen, mbssid_elem, sub_elem) but never advances mbssid_elem or sub_elem inside the body. Each iteration therefore searches for a continuation that follows the same fixed pair; the helper returns the same next_mbssid; and the same next_sub bytes are memcpy()'d into merged_ie at a growing offset until the buffer fills. Advance both mbssid_elem and sub_elem to the just-consumed continuation so the next call to cfg80211_get_profile_continuation() searches for a further continuation beyond it (or returns NULL when none exists). A specially-crafted malicious beacon can take advantage of this bug to cause the kernel to spend an excessive amount of time in cfg80211_merge_profile (up to as much as 2ms per beacon received), which could theoretically be abused in some way. Cc: stable@vger.kernel.org Fixes: fe806e4992c9 ("cfg80211: support profile split between elements") Signed-off-by: John Walker Link: https://patch.msgid.link/20260507230720.64783-1-johnwalker0@gmail.com Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman

wifi: cfg80211: Fix use_for flag update on BSS refresh

2026-03-04T12:19:58+00:00

[ Upstream commit 4073ea516106e5f98ed0476f89cdede8baa98d37 ] Userspace may fail to connect to certain BSS that were initially marked as unusable due to regulatory restrictions (use_for = 0, e.g., 6 GHz power type mismatch). Even after these restrictions are removed and the BSS becomes usable, connection attempts still fail. The issue occurs in cfg80211_update_known_bss() where the use_for flag is updated using bitwise AND (&=) instead of direct assignment. Once a BSS is marked with use_for = 0, the AND operation masks out any subsequent non-zero values, permanently keeping the flag at 0. This causes __cfg80211_get_bss(), invoked by nl80211_assoc_bss(), to fail the check "(bss->pub.use_for & use_for) != use_for", thereby blocking association. Replace the bitwise AND operation with direct assignment so the use_for flag accurately reflects the current BSS state. Fixes: d02a12b8e4bb ("wifi: cfg80211: add BSS usage reporting") Signed-off-by: Huang Chenming Link: https://patch.msgid.link/20251209025733.2098456-1-chenming.huang@oss.qualcomm.com Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: cfg80211: fix use-after-free in cmp_bss()

2025-09-09T16:58:05+00:00

[ Upstream commit 26e84445f02ce6b2fe5f3e0e28ff7add77f35e08 ] Following bss_free() quirk introduced in commit 776b3580178f ("cfg80211: track hidden SSID networks properly"), adjust cfg80211_update_known_bss() to free the last beacon frame elements only if they're not shared via the corresponding 'hidden_beacon_bss' pointer. Reported-by: syzbot+30754ca335e6fb7e3092@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=30754ca335e6fb7e3092 Fixes: 3ab8227d3e7d ("cfg80211: refactor cfg80211_bss_update") Signed-off-by: Dmitry Antipov Link: https://patch.msgid.link/20250813135236.799384-1-dmantipov@yandex.ru Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: cfg80211/mac80211: correctly parse S1G beacon optional elements

2025-06-19T13:32:19+00:00

[ Upstream commit 1e1f706fc2ce90eaaf3480b3d5f27885960d751c ] S1G beacons are not traditional beacons but a type of extension frame. Extension frames contain the frame control and duration fields, followed by zero or more optional fields before the frame body. These optional fields are distinct from the variable length elements. The presence of optional fields is indicated in the frame control field. To correctly locate the elements offset, the frame control must be parsed to identify which optional fields are present. Currently, mac80211 parses S1G beacons based on fixed assumptions about the frame layout, without inspecting the frame control field. This can result in incorrect offsets to the "variable" portion of the frame. Properly parse S1G beacon frames by using the field lengths defined in IEEE 802.11-2024, section 9.3.4.3, ensuring that the elements offset is calculated accurately. Fixes: 9eaffe5078ca ("cfg80211: convert S1G beacon to scan results") Fixes: cd418ba63f0c ("mac80211: convert S1G beacon to scan results") Signed-off-by: Lachlan Hodges Link: https://patch.msgid.link/20250603053538.468562-1-lachlan.hodges@morsemicro.com Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: cfg80211: fix out-of-bounds access during multi-link element defragmentation

2025-05-18T06:24:47+00:00

commit 023c1f2f0609218103cbcb48e0104b144d4a16dc upstream. Currently during the multi-link element defragmentation process, the multi-link element length added to the total IEs length when calculating the length of remaining IEs after the multi-link element in cfg80211_defrag_mle(). This could lead to out-of-bounds access if the multi-link element or its corresponding fragment elements are the last elements in the IEs buffer. To address this issue, correctly calculate the remaining IEs length by deducting the multi-link element end offset from total IEs end offset. Cc: stable@vger.kernel.org Fixes: 2481b5da9c6b ("wifi: cfg80211: handle BSS data contained in ML probe responses") Signed-off-by: Veerendranath Jakkam Link: https://patch.msgid.link/20250424-fix_mle_defragmentation_oob_access-v1-1-84412a1743fa@quicinc.com Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman

wifi: cfg80211: adjust allocation of colocated AP data

2025-02-08T08:57:22+00:00

[ Upstream commit 1a0d24775cdee2b8dc14bfa4f4418c930ab1ac57 ] In 'cfg80211_scan_6ghz()', an instances of 'struct cfg80211_colocated_ap' are allocated as if they would have 'ssid' as trailing VLA member. Since this is not so, extra IEEE80211_MAX_SSID_LEN bytes are not needed. Briefly tested with KUnit. Fixes: c8cb5b854b40 ("nl80211/cfg80211: support 6 GHz scanning") Signed-off-by: Dmitry Antipov Link: https://patch.msgid.link/20250113155417.552587-1-dmantipov@yandex.ru Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin

wifi: cfg80211: Move cfg80211_scan_req_add_chan() n_channels increment earlier

2025-02-08T08:57:14+00:00

[ Upstream commit 3a0168626c138734490bc52c4105ce8e79d2f923 ] Since adding __counted_by(n_channels) to struct cfg80211_scan_request, anything adding to the channels array must increment n_channels first. Move n_channels increment earlier. Reported-by: John Rowley Closes: https://lore.kernel.org/stable/1815535c709ba9d9.156c6a5c9cdf6e59.b249b6b6a5ee4634@localhost.localdomain/ Fixes: aa4ec06c455d ("wifi: cfg80211: use __counted_by where appropriate") Signed-off-by: Kees Cook Reviewed-by: Gustavo A. R. Silva Link: https://patch.msgid.link/20241230183610.work.680-kees@kernel.org Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin