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, 408 insertions, 0 deletions

diff --git a/net/wireless/tests/chan.c b/net/wireless/tests/chan.c
new file mode 100644
index 000000000..65eb18c49
--- /dev/null
+++ b/net/wireless/tests/chan.c
@@ -0,0 +1,408 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * KUnit tests for channel helper functions
+ *
+ * Copyright (C) 2023-2024, 2026 Intel Corporation
+ */
+#include <net/cfg80211.h>
+#include <kunit/test.h>
+
+MODULE_IMPORT_NS("EXPORTED_FOR_KUNIT_TESTING");
+
+static struct ieee80211_channel chan_2ghz_1 = {
+	.band = NL80211_BAND_2GHZ,
+	.center_freq = 2412,
+};
+
+static struct ieee80211_channel chan_6ghz_1 = {
+	.band = NL80211_BAND_6GHZ,
+	.center_freq = 5955,
+};
+
+static struct ieee80211_channel chan_6ghz_5 = {
+	.band = NL80211_BAND_6GHZ,
+	.center_freq = 5975,
+};
+
+static struct ieee80211_channel chan_6ghz_105 = {
+	.band = NL80211_BAND_6GHZ,
+	.center_freq = 6475,
+};
+
+static const struct chandef_compat_case {
+	const char *desc;
+	/* leave c1 empty for tests for identical */
+	struct cfg80211_chan_def c1, c2;
+	/* we test both ways around, so c2 should always be the compat one */
+	bool compat;
+} chandef_compat_cases[] = {
+	{
+		.desc = "identical non-HT",
+		.c2 = {
+			.width = NL80211_CHAN_WIDTH_20_NOHT,
+			.chan = &chan_6ghz_1,
+			.center_freq1 = 5955,
+		},
+		.compat = true,
+	},
+	{
+		.desc = "identical 20 MHz",
+		.c2 = {
+			.width = NL80211_CHAN_WIDTH_20,
+			.chan = &chan_6ghz_1,
+			.center_freq1 = 5955,
+		},
+		.compat = true,
+	},
+	{
+		.desc = "identical 40 MHz",
+		.c2 = {
+			.width = NL80211_CHAN_WIDTH_40,
+			.chan = &chan_6ghz_1,
+			.center_freq1 = 5955 + 10,
+		},
+		.compat = true,
+	},
+	{
+		.desc = "identical 80 MHz",
+		.c2 = {
+			.width = NL80211_CHAN_WIDTH_80,
+			.chan = &chan_6ghz_1,
+			.center_freq1 = 5955 + 10 + 20,
+		},
+		.compat = true,
+	},
+	{
+		.desc = "identical 160 MHz",
+		.c2 = {
+			.width = NL80211_CHAN_WIDTH_160,
+			.chan = &chan_6ghz_1,
+			.center_freq1 = 5955 + 10 + 20 + 40,
+		},
+		.compat = true,
+	},
+	{
+		.desc = "identical 320 MHz",
+		.c2 = {
+			.width = NL80211_CHAN_WIDTH_320,
+			.chan = &chan_6ghz_1,
+			.center_freq1 = 5955 + 10 + 20 + 40 + 80,
+		},
+		.compat = true,
+	},
+	{
+		.desc = "20 MHz in 320 MHz\n",
+		.c1 = {
+			.width = NL80211_CHAN_WIDTH_20,
+			.chan = &chan_6ghz_1,
+			.center_freq1 = 5955,
+		},
+		.c2 = {
+			.width = NL80211_CHAN_WIDTH_320,
+			.chan = &chan_6ghz_1,
+			.center_freq1 = 5955 + 10 + 20 + 40 + 80,
+		},
+		.compat = true,
+	},
+	{
+		.desc = "different 20 MHz",
+		.c1 = {
+			.width = NL80211_CHAN_WIDTH_20,
+			.chan = &chan_6ghz_1,
+			.center_freq1 = 5955,
+		},
+		.c2 = {
+			.width = NL80211_CHAN_WIDTH_20,
+			.chan = &chan_6ghz_5,
+			.center_freq1 = 5975,
+		},
+	},
+	{
+		.desc = "different primary 320 MHz",
+		.c1 = {
+			.width = NL80211_CHAN_WIDTH_320,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 + 110,
+		},
+		.c2 = {
+			.width = NL80211_CHAN_WIDTH_320,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 - 50,
+		},
+	},
+	{
+		/* similar to previous test but one has lower BW */
+		.desc = "matching primary 160 MHz",
+		.c1 = {
+			.width = NL80211_CHAN_WIDTH_160,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 + 30,
+		},
+		.c2 = {
+			.width = NL80211_CHAN_WIDTH_320,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 - 50,
+		},
+		.compat = true,
+	},
+	{
+		.desc = "matching primary 160 MHz & punctured secondary 160 Mhz",
+		.c1 = {
+			.width = NL80211_CHAN_WIDTH_160,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 + 30,
+		},
+		.c2 = {
+			.width = NL80211_CHAN_WIDTH_320,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 - 50,
+			.punctured = 0xf,
+		},
+		.compat = true,
+	},
+	{
+		.desc = "matching primary 160 MHz & punctured matching",
+		.c1 = {
+			.width = NL80211_CHAN_WIDTH_160,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 + 30,
+			.punctured = 0xc0,
+		},
+		.c2 = {
+			.width = NL80211_CHAN_WIDTH_320,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 - 50,
+			.punctured = 0xc000,
+		},
+		.compat = true,
+	},
+	{
+		.desc = "matching primary 160 MHz & punctured not matching",
+		.c1 = {
+			.width = NL80211_CHAN_WIDTH_160,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 + 30,
+			.punctured = 0x80,
+		},
+		.c2 = {
+			.width = NL80211_CHAN_WIDTH_320,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 - 50,
+			.punctured = 0xc000,
+		},
+	},
+};
+
+KUNIT_ARRAY_PARAM_DESC(chandef_compat, chandef_compat_cases, desc)
+
+static void test_chandef_compat(struct kunit *test)
+{
+	const struct chandef_compat_case *params = test->param_value;
+	const struct cfg80211_chan_def *ret, *expect;
+	struct cfg80211_chan_def c1 = params->c1;
+
+	/* tests with identical ones */
+	if (!params->c1.chan)
+		c1 = params->c2;
+
+	KUNIT_EXPECT_EQ(test, cfg80211_chandef_valid(&c1), true);
+	KUNIT_EXPECT_EQ(test, cfg80211_chandef_valid(&params->c2), true);
+
+	expect = params->compat ? &params->c2 : NULL;
+
+	ret = cfg80211_chandef_compatible(&c1, &params->c2);
+	KUNIT_EXPECT_PTR_EQ(test, ret, expect);
+
+	if (!params->c1.chan)
+		expect = &c1;
+
+	ret = cfg80211_chandef_compatible(&params->c2, &c1);
+	KUNIT_EXPECT_PTR_EQ(test, ret, expect);
+}
+
+static const struct chandef_dbe_case {
+	const char *desc;
+	struct cfg80211_chan_def c;
+	u8 dbe[3];
+	bool fails;
+	u16 cf1;
+} chandef_dbe_cases[] = {
+	{
+		.desc = "non-HT failure",
+		.c = {
+			.width = NL80211_CHAN_WIDTH_20_NOHT,
+			.chan = &chan_6ghz_1,
+			.center_freq1 = 5955,
+		},
+		.dbe[0] = IEEE80211_UHR_DBE_OPER_BW_40,
+		.fails = true,
+	},
+	{
+		.desc = "2.4 GHz fails",
+		.c = {
+			.width = NL80211_CHAN_WIDTH_20,
+			.chan = &chan_2ghz_1,
+			.center_freq1 = 2412,
+		},
+		.dbe[0] = IEEE80211_UHR_DBE_OPER_BW_40,
+		.fails = true,
+	},
+	{
+		.desc = "DBE narrower",
+		.c = {
+			.width = NL80211_CHAN_WIDTH_320,
+			.chan = &chan_6ghz_1,
+			.center_freq1 = 5955 + 10 + 20 + 40 + 80,
+		},
+		.dbe[0] = IEEE80211_UHR_DBE_OPER_BW_160,
+		.fails = true,
+	},
+	{
+		.desc = "DBE to 320-1",
+		.c = {
+			.width = NL80211_CHAN_WIDTH_160,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 + 30,
+		},
+		.dbe[0] = IEEE80211_UHR_DBE_OPER_BW_320_1,
+		.cf1 = 6425,
+	},
+	{
+		.desc = "DBE to 320-2",
+		.c = {
+			.width = NL80211_CHAN_WIDTH_160,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 + 30,
+		},
+		.dbe[0] = IEEE80211_UHR_DBE_OPER_BW_320_2,
+		.cf1 = 6585,
+	},
+	{
+		.desc = "bad disabled subchannel bitmap - not enough in BSS (1)",
+		.c = {
+			.width = NL80211_CHAN_WIDTH_160,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 + 30,
+			.punctured = 0x0001,
+		},
+		.dbe[0] = IEEE80211_UHR_DBE_OPER_BW_320_1 |
+			  IEEE80211_UHR_DBE_OPER_DIS_SUBCHANNEL_BITMAP_PRES,
+		/* DBE disabled subchannel bitmap == 0 */
+		.fails = true,
+	},
+	{
+		.desc = "bad disabled subchannel bitmap - too much in BSS (1)",
+		.c = {
+			.width = NL80211_CHAN_WIDTH_160,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 + 30,
+			.punctured = 0x0001,
+		},
+		.dbe[0] = IEEE80211_UHR_DBE_OPER_BW_320_1 |
+			  IEEE80211_UHR_DBE_OPER_DIS_SUBCHANNEL_BITMAP_PRES,
+		/* DBE disabled subchannel bitmap == 0x0300 */
+		.dbe[2] = 0x03,
+		.fails = true,
+	},
+	{
+		.desc = "bad disabled subchannel bitmap - not enough in BSS (2)",
+		.c = {
+			.width = NL80211_CHAN_WIDTH_160,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 + 30,
+			.punctured = 0x0001,
+		},
+		.dbe[0] = IEEE80211_UHR_DBE_OPER_BW_320_2 |
+			  IEEE80211_UHR_DBE_OPER_DIS_SUBCHANNEL_BITMAP_PRES,
+		/* DBE disabled subchannel bitmap == 0 */
+		.fails = true,
+	},
+	{
+		.desc = "bad disabled subchannel bitmap - too much in BSS (2)",
+		.c = {
+			.width = NL80211_CHAN_WIDTH_160,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 + 30,
+			.punctured = 0x0001,
+		},
+		.dbe[0] = IEEE80211_UHR_DBE_OPER_BW_320_2 |
+			  IEEE80211_UHR_DBE_OPER_DIS_SUBCHANNEL_BITMAP_PRES,
+		/* DBE disabled subchannel bitmap == 0x03 */
+		.dbe[1] = 0x03,
+		.fails = true,
+	},
+	{
+		.desc = "bad disabled subchannel bitmap - bad bitmap",
+		.c = {
+			.width = NL80211_CHAN_WIDTH_160,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 + 30,
+			.punctured = 0x0001,
+		},
+		.dbe[0] = IEEE80211_UHR_DBE_OPER_BW_320_1 |
+			  IEEE80211_UHR_DBE_OPER_DIS_SUBCHANNEL_BITMAP_PRES,
+		/* DBE disabled subchannel bitmap == 0x1100 */
+		.dbe[2] = 0x11,
+		.fails = true,
+	},
+	{
+		.desc = "good disabled subchannel bitmap (1)",
+		.c = {
+			.width = NL80211_CHAN_WIDTH_160,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 + 30,
+			.punctured = 0x0003,
+		},
+		.dbe[0] = IEEE80211_UHR_DBE_OPER_BW_320_1 |
+			  IEEE80211_UHR_DBE_OPER_DIS_SUBCHANNEL_BITMAP_PRES,
+		/* DBE disabled subchannel bitmap == 0x0300 */
+		.dbe[2] = 0x03,
+		.cf1 = 6425,
+	},
+	{
+		.desc = "good disabled subchannel bitmap (2)",
+		.c = {
+			.width = NL80211_CHAN_WIDTH_160,
+			.chan = &chan_6ghz_105,
+			.center_freq1 = 6475 + 30,
+			.punctured = 0x0003,
+		},
+		.dbe[0] = IEEE80211_UHR_DBE_OPER_BW_320_2 |
+			  IEEE80211_UHR_DBE_OPER_DIS_SUBCHANNEL_BITMAP_PRES,
+		/* DBE disabled subchannel bitmap == 0x0003 */
+		.dbe[1] = 0x03,
+		.cf1 = 6585,
+	},
+};
+
+KUNIT_ARRAY_PARAM_DESC(chandef_dbe, chandef_dbe_cases, desc)
+
+static void test_chandef_dbe(struct kunit *test)
+{
+	const struct chandef_dbe_case *params = test->param_value;
+	struct cfg80211_chan_def c = params->c;
+	int ret;
+
+	KUNIT_EXPECT_EQ(test, cfg80211_chandef_valid(&params->c), true);
+
+	ret = cfg80211_chandef_add_dbe(&c, (void *)params->dbe);
+	KUNIT_EXPECT_EQ(test, ret != 0, params->fails);
+
+	if (params->fails)
+		return;
+
+	KUNIT_EXPECT_EQ(test, c.center_freq1, params->cf1);
+}
+
+static struct kunit_case chandef_test_cases[] = {
+	KUNIT_CASE_PARAM(test_chandef_compat, chandef_compat_gen_params),
+	KUNIT_CASE_PARAM(test_chandef_dbe, chandef_dbe_gen_params),
+	{}
+};
+
+static struct kunit_suite chandef = {
+	.name = "cfg80211-chandef",
+	.test_cases = chandef_test_cases,
+};
+
+kunit_test_suite(chandef);