ftrace: Synchronize the initialization of ftrace_opsgrafted

There's some internal state that ftrace_ops needs to have set, but since
it can be declared outside of the ftrace.c code, it calls
ftrace_ops_init() on the ops in every global function. The issue is that
if two tasks call it on the same ops at the same time it is possible to
have the initialization of one corrupt the initialization of the other
call.

Create a ops_mutex to use to synchronize every initialization of the
ftrace_ops. The mutex is taken within checking the ftrace_ops flag that
states it was initializied but the flag is checked again after the mutex
has been taken. Checking first outside the mutex allows it to shortcut
having to take the mutex. But then the check needs to be done again after
the mute is taken in case of races.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home
Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock")
Reported-by: sashiko-bot@kernel.org
Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 378 insertions, 0 deletions

diff --git a/net/wireless/wext-sme.c b/net/wireless/wext-sme.c
new file mode 100644
index 000000000..b5914f365
--- /dev/null
+++ b/net/wireless/wext-sme.c
@@ -0,0 +1,378 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * cfg80211 wext compat for managed mode.
+ *
+ * Copyright 2009	Johannes Berg <johannes@sipsolutions.net>
+ * Copyright (C) 2009, 2020-2023 Intel Corporation
+ */
+
+#include <linux/export.h>
+#include <linux/etherdevice.h>
+#include <linux/if_arp.h>
+#include <linux/slab.h>
+#include <net/cfg80211.h>
+#include <net/cfg80211-wext.h>
+#include "wext-compat.h"
+#include "nl80211.h"
+
+int cfg80211_mgd_wext_connect(struct cfg80211_registered_device *rdev,
+			      struct wireless_dev *wdev)
+{
+	struct cfg80211_cached_keys *ck = NULL;
+	const u8 *prev_bssid = NULL;
+	int err, i;
+
+	ASSERT_RTNL();
+	lockdep_assert_wiphy(wdev->wiphy);
+
+	if (!netif_running(wdev->netdev))
+		return 0;
+
+	wdev->wext.connect.ie = wdev->wext.ie;
+	wdev->wext.connect.ie_len = wdev->wext.ie_len;
+
+	/* Use default background scan period */
+	wdev->wext.connect.bg_scan_period = -1;
+
+	if (wdev->wext.keys) {
+		wdev->wext.keys->def = wdev->wext.default_key;
+		if (wdev->wext.default_key != -1)
+			wdev->wext.connect.privacy = true;
+	}
+
+	if (!wdev->wext.connect.ssid_len)
+		return 0;
+
+	if (wdev->wext.keys && wdev->wext.keys->def != -1) {
+		ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
+		if (!ck)
+			return -ENOMEM;
+		for (i = 0; i < 4; i++)
+			ck->params[i].key = ck->data[i];
+	}
+
+	if (wdev->wext.prev_bssid_valid)
+		prev_bssid = wdev->wext.prev_bssid;
+
+	err = cfg80211_connect(rdev, wdev->netdev,
+			       &wdev->wext.connect, ck, prev_bssid);
+	if (err)
+		kfree_sensitive(ck);
+
+	return err;
+}
+
+int cfg80211_mgd_wext_siwfreq(struct net_device *dev,
+			      struct iw_request_info *info,
+			      struct iw_freq *wextfreq, char *extra)
+{
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
+	struct ieee80211_channel *chan = NULL;
+	int err, freq;
+
+	/* call only for station! */
+	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
+		return -EINVAL;
+
+	freq = cfg80211_wext_freq(wextfreq);
+	if (freq < 0)
+		return freq;
+
+	if (freq) {
+		chan = ieee80211_get_channel(wdev->wiphy, freq);
+		if (!chan)
+			return -EINVAL;
+		if (chan->flags & IEEE80211_CHAN_DISABLED)
+			return -EINVAL;
+	}
+
+	if (wdev->conn) {
+		bool event = true;
+
+		if (wdev->wext.connect.channel == chan)
+			return 0;
+
+		/* if SSID set, we'll try right again, avoid event */
+		if (wdev->wext.connect.ssid_len)
+			event = false;
+		err = cfg80211_disconnect(rdev, dev,
+					  WLAN_REASON_DEAUTH_LEAVING, event);
+		if (err)
+			return err;
+	}
+
+	wdev->wext.connect.channel = chan;
+	return cfg80211_mgd_wext_connect(rdev, wdev);
+}
+
+int cfg80211_mgd_wext_giwfreq(struct net_device *dev,
+			      struct iw_request_info *info,
+			      struct iw_freq *freq, char *extra)
+{
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	struct ieee80211_channel *chan = NULL;
+
+	/* call only for station! */
+	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
+		return -EINVAL;
+
+	if (wdev->valid_links)
+		return -EOPNOTSUPP;
+
+	if (wdev->links[0].client.current_bss)
+		chan = wdev->links[0].client.current_bss->pub.channel;
+	else if (wdev->wext.connect.channel)
+		chan = wdev->wext.connect.channel;
+
+	if (chan) {
+		freq->m = chan->center_freq;
+		freq->e = 6;
+		return 0;
+	}
+
+	/* no channel if not joining */
+	return -EINVAL;
+}
+
+int cfg80211_mgd_wext_siwessid(struct net_device *dev,
+			       struct iw_request_info *info,
+			       struct iw_point *data, char *ssid)
+{
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
+	size_t len = data->length;
+	int err;
+
+	/* call only for station! */
+	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
+		return -EINVAL;
+
+	if (!data->flags)
+		len = 0;
+
+	/* iwconfig uses nul termination in SSID.. */
+	if (len > 0 && ssid[len - 1] == '\0')
+		len--;
+
+	if (wdev->conn) {
+		bool event = true;
+
+		if (wdev->wext.connect.ssid && len &&
+		    len == wdev->wext.connect.ssid_len &&
+		    memcmp(wdev->wext.connect.ssid, ssid, len) == 0)
+			return 0;
+
+		/* if SSID set now, we'll try to connect, avoid event */
+		if (len)
+			event = false;
+		err = cfg80211_disconnect(rdev, dev,
+					  WLAN_REASON_DEAUTH_LEAVING, event);
+		if (err)
+			return err;
+	}
+
+	wdev->wext.prev_bssid_valid = false;
+	wdev->wext.connect.ssid = wdev->wext.ssid;
+	memcpy(wdev->wext.ssid, ssid, len);
+	wdev->wext.connect.ssid_len = len;
+
+	wdev->wext.connect.crypto.control_port = false;
+	wdev->wext.connect.crypto.control_port_ethertype =
+					cpu_to_be16(ETH_P_PAE);
+
+	return cfg80211_mgd_wext_connect(rdev, wdev);
+}
+
+int cfg80211_mgd_wext_giwessid(struct net_device *dev,
+			       struct iw_request_info *info,
+			       struct iw_point *data, char *ssid)
+{
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	int ret = 0;
+
+	/* call only for station! */
+	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
+		return -EINVAL;
+
+	if (wdev->valid_links)
+		return -EINVAL;
+
+	data->flags = 0;
+
+	if (wdev->links[0].client.current_bss) {
+		const struct element *ssid_elem;
+
+		rcu_read_lock();
+		ssid_elem = ieee80211_bss_get_elem(
+				&wdev->links[0].client.current_bss->pub,
+				WLAN_EID_SSID);
+		if (ssid_elem) {
+			data->flags = 1;
+			data->length = ssid_elem->datalen;
+			if (data->length > IW_ESSID_MAX_SIZE)
+				ret = -EINVAL;
+			else
+				memcpy(ssid, ssid_elem->data, data->length);
+		}
+		rcu_read_unlock();
+	} else if (wdev->wext.connect.ssid && wdev->wext.connect.ssid_len) {
+		data->flags = 1;
+		data->length = wdev->wext.connect.ssid_len;
+		memcpy(ssid, wdev->wext.connect.ssid, data->length);
+	}
+
+	return ret;
+}
+
+int cfg80211_mgd_wext_siwap(struct net_device *dev,
+			    struct iw_request_info *info,
+			    struct sockaddr *ap_addr, char *extra)
+{
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
+	u8 *bssid = ap_addr->sa_data;
+	int err;
+
+	/* call only for station! */
+	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
+		return -EINVAL;
+
+	if (ap_addr->sa_family != ARPHRD_ETHER)
+		return -EINVAL;
+
+	/* automatic mode */
+	if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
+		bssid = NULL;
+
+	if (wdev->conn) {
+		/* both automatic */
+		if (!bssid && !wdev->wext.connect.bssid)
+			return 0;
+
+		/* fixed already - and no change */
+		if (wdev->wext.connect.bssid && bssid &&
+		    ether_addr_equal(bssid, wdev->wext.connect.bssid))
+			return 0;
+
+		err = cfg80211_disconnect(rdev, dev,
+					  WLAN_REASON_DEAUTH_LEAVING, false);
+		if (err)
+			return err;
+	}
+
+	if (bssid) {
+		memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
+		wdev->wext.connect.bssid = wdev->wext.bssid;
+	} else
+		wdev->wext.connect.bssid = NULL;
+
+	return cfg80211_mgd_wext_connect(rdev, wdev);
+}
+
+int cfg80211_mgd_wext_giwap(struct net_device *dev,
+			    struct iw_request_info *info,
+			    struct sockaddr *ap_addr, char *extra)
+{
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+
+	/* call only for station! */
+	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
+		return -EINVAL;
+
+	ap_addr->sa_family = ARPHRD_ETHER;
+
+	if (wdev->valid_links)
+		return -EOPNOTSUPP;
+
+	if (wdev->links[0].client.current_bss)
+		memcpy(ap_addr->sa_data,
+		       wdev->links[0].client.current_bss->pub.bssid,
+		       ETH_ALEN);
+	else
+		eth_zero_addr(ap_addr->sa_data);
+
+	return 0;
+}
+
+int cfg80211_wext_siwgenie(struct net_device *dev,
+			   struct iw_request_info *info,
+			   union iwreq_data *wrqu, char *extra)
+{
+	struct iw_point *data = &wrqu->data;
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
+	int ie_len = data->length;
+	u8 *ie = extra;
+
+	if (wdev->iftype != NL80211_IFTYPE_STATION)
+		return -EOPNOTSUPP;
+
+	if (!ie_len)
+		ie = NULL;
+
+	guard(wiphy)(wdev->wiphy);
+
+	/* no change */
+	if (wdev->wext.ie_len == ie_len &&
+	    memcmp(wdev->wext.ie, ie, ie_len) == 0)
+		return 0;
+
+	if (ie_len) {
+		const struct element *elem;
+
+		for_each_element(elem, extra, ie_len) {
+			/* nothing */
+		}
+
+		if (!for_each_element_completed(elem, extra, ie_len))
+			return -EINVAL;
+
+		ie = kmemdup(extra, ie_len, GFP_KERNEL);
+		if (!ie)
+			return -ENOMEM;
+	} else {
+		ie = NULL;
+	}
+
+	kfree(wdev->wext.ie);
+	wdev->wext.ie = ie;
+	wdev->wext.ie_len = ie_len;
+
+	if (wdev->conn)
+		return cfg80211_disconnect(rdev, dev,
+					   WLAN_REASON_DEAUTH_LEAVING, false);
+
+	/* userspace better not think we'll reconnect */
+	return 0;
+}
+
+int cfg80211_wext_siwmlme(struct net_device *dev,
+			  struct iw_request_info *info,
+			  union iwreq_data *wrqu, char *extra)
+{
+	struct wireless_dev *wdev = dev->ieee80211_ptr;
+	struct iw_mlme *mlme = (struct iw_mlme *)extra;
+	struct cfg80211_registered_device *rdev;
+
+	if (!wdev)
+		return -EOPNOTSUPP;
+
+	rdev = wiphy_to_rdev(wdev->wiphy);
+
+	if (wdev->iftype != NL80211_IFTYPE_STATION)
+		return -EINVAL;
+
+	if (mlme->addr.sa_family != ARPHRD_ETHER)
+		return -EINVAL;
+
+	guard(wiphy)(&rdev->wiphy);
+
+	switch (mlme->cmd) {
+	case IW_MLME_DEAUTH:
+	case IW_MLME_DISASSOC:
+		return cfg80211_disconnect(rdev, dev, mlme->reason_code, true);
+	default:
+		return -EOPNOTSUPP;
+	}
+}