From 49f27f29446a5bfe633dd2cc0cfebd48a1a5e77f Mon Sep 17 00:00:00 2001 From: Vitaliy Shevtsov Date: Fri, 31 Jan 2025 20:26:55 +0500 Subject: wifi: nl80211: reject cooked mode if it is set along with other flags It is possible to set both MONITOR_FLAG_COOK_FRAMES and MONITOR_FLAG_ACTIVE flags simultaneously on the same monitor interface from the userspace. This causes a sub-interface to be created with no IEEE80211_SDATA_IN_DRIVER bit set because the monitor interface is in the cooked state and it takes precedence over all other states. When the interface is then being deleted the kernel calls WARN_ONCE() from check_sdata_in_driver() because of missing that bit. Fix this by rejecting MONITOR_FLAG_COOK_FRAMES if it is set along with other flags. Found by Linux Verification Center (linuxtesting.org) with Syzkaller. Fixes: 66f7ac50ed7c ("nl80211: Add monitor interface configuration flags") Cc: stable@vger.kernel.org Reported-by: syzbot+2e5c1e55b9e5c28a3da7@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=2e5c1e55b9e5c28a3da7 Signed-off-by: Vitaliy Shevtsov Link: https://patch.msgid.link/20250131152657.5606-1-v.shevtsov@mt-integration.ru Signed-off-by: Johannes Berg --- net/wireless/nl80211.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'net/wireless') diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index d7d3da0f6833..fdb2aac951d1 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -4220,6 +4220,11 @@ static int parse_monitor_flags(struct nlattr *nla, u32 *mntrflags) if (flags[flag]) *mntrflags |= (1< Date: Fri, 28 Feb 2025 16:46:57 +0300 Subject: wifi: cfg80211: regulatory: improve invalid hints checking MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Syzbot keeps reporting an issue [1] that occurs when erroneous symbols sent from userspace get through into user_alpha2[] via regulatory_hint_user() call. Such invalid regulatory hints should be rejected. While a sanity check from commit 47caf685a685 ("cfg80211: regulatory: reject invalid hints") looks to be enough to deter these very cases, there is a way to get around it due to 2 reasons. 1) The way isalpha() works, symbols other than latin lower and upper letters may be used to determine a country/domain. For instance, greek letters will also be considered upper/lower letters and for such characters isalpha() will return true as well. However, ISO-3166-1 alpha2 codes should only hold latin characters. 2) While processing a user regulatory request, between reg_process_hint_user() and regulatory_hint_user() there happens to be a call to queue_regulatory_request() which modifies letters in request->alpha2[] with toupper(). This works fine for latin symbols, less so for weird letter characters from the second part of _ctype[]. Syzbot triggers a warning in is_user_regdom_saved() by first sending over an unexpected non-latin letter that gets malformed by toupper() into a character that ends up failing isalpha() check. Prevent this by enhancing is_an_alpha2() to ensure that incoming symbols are latin letters and nothing else. [1] Syzbot report: ------------[ cut here ]------------ Unexpected user alpha2: A� WARNING: CPU: 1 PID: 964 at net/wireless/reg.c:442 is_user_regdom_saved net/wireless/reg.c:440 [inline] WARNING: CPU: 1 PID: 964 at net/wireless/reg.c:442 restore_alpha2 net/wireless/reg.c:3424 [inline] WARNING: CPU: 1 PID: 964 at net/wireless/reg.c:442 restore_regulatory_settings+0x3c0/0x1e50 net/wireless/reg.c:3516 Modules linked in: CPU: 1 UID: 0 PID: 964 Comm: kworker/1:2 Not tainted 6.12.0-rc5-syzkaller-00044-gc1e939a21eb1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_power_efficient crda_timeout_work RIP: 0010:is_user_regdom_saved net/wireless/reg.c:440 [inline] RIP: 0010:restore_alpha2 net/wireless/reg.c:3424 [inline] RIP: 0010:restore_regulatory_settings+0x3c0/0x1e50 net/wireless/reg.c:3516 ... Call Trace: crda_timeout_work+0x27/0x50 net/wireless/reg.c:542 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Reported-by: syzbot+e10709ac3c44f3d4e800@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=e10709ac3c44f3d4e800 Fixes: 09d989d179d0 ("cfg80211: add regulatory hint disconnect support") Cc: stable@kernel.org Signed-off-by: Nikita Zhandarovich Link: https://patch.msgid.link/20250228134659.1577656-1-n.zhandarovich@fintech.ru Signed-off-by: Johannes Berg --- net/wireless/reg.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/wireless') diff --git a/net/wireless/reg.c b/net/wireless/reg.c index 2dd0533e7660..212e9561aae7 100644 --- a/net/wireless/reg.c +++ b/net/wireless/reg.c @@ -407,7 +407,8 @@ static bool is_an_alpha2(const char *alpha2) { if (!alpha2) return false; - return isalpha(alpha2[0]) && isalpha(alpha2[1]); + return isascii(alpha2[0]) && isalpha(alpha2[0]) && + isascii(alpha2[1]) && isalpha(alpha2[1]); } static bool alpha2_equal(const char *alpha2_x, const char *alpha2_y) -- cgit v1.2.3-59-g8ed1b From 1f860eb4cdda634589d75e78ff586d5dff20b8af Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Mon, 3 Mar 2025 11:05:36 +0100 Subject: wifi: nl80211: disable multi-link reconfiguration Both the APIs in cfg80211 and the implementation in mac80211 aren't really ready yet, we have a large number of fixes. In addition, it's not possible right now to discover support for this feature from userspace. Disable it for now, there's no rush. Link: https://patch.msgid.link/20250303110538.fbeef42a5687.Iab122c22137e5675ebd99f5c031e30c0e5c7af2e@changeid Signed-off-by: Johannes Berg --- net/wireless/nl80211.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/wireless') diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index fdb2aac951d1..e87267fbb442 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -16534,7 +16534,7 @@ static int nl80211_assoc_ml_reconf(struct sk_buff *skb, struct genl_info *info) goto out; } - err = cfg80211_assoc_ml_reconf(rdev, dev, links, rem_links); + err = -EOPNOTSUPP; out: for (link_id = 0; link_id < ARRAY_SIZE(links); link_id++) -- cgit v1.2.3-59-g8ed1b