From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops 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 --- lib/tests/uuid_kunit.c | 162 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 162 insertions(+) create mode 100644 lib/tests/uuid_kunit.c (limited to 'lib/tests/uuid_kunit.c') diff --git a/lib/tests/uuid_kunit.c b/lib/tests/uuid_kunit.c new file mode 100644 index 000000000..2ef64fbe6 --- /dev/null +++ b/lib/tests/uuid_kunit.c @@ -0,0 +1,162 @@ +// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 +/* + * Test cases for lib/uuid.c module. + */ + +#include +#include + +struct test_uuid_data { + const char *uuid; + guid_t le; + uuid_t be; +}; + +static const struct test_uuid_data test_uuid_test_data[] = { + { + .uuid = "c33f4995-3701-450e-9fbf-206a2e98e576", + .le = GUID_INIT(0xc33f4995, 0x3701, 0x450e, 0x9f, 0xbf, 0x20, 0x6a, 0x2e, 0x98, 0xe5, 0x76), + .be = UUID_INIT(0xc33f4995, 0x3701, 0x450e, 0x9f, 0xbf, 0x20, 0x6a, 0x2e, 0x98, 0xe5, 0x76), + }, + { + .uuid = "64b4371c-77c1-48f9-8221-29f054fc023b", + .le = GUID_INIT(0x64b4371c, 0x77c1, 0x48f9, 0x82, 0x21, 0x29, 0xf0, 0x54, 0xfc, 0x02, 0x3b), + .be = UUID_INIT(0x64b4371c, 0x77c1, 0x48f9, 0x82, 0x21, 0x29, 0xf0, 0x54, 0xfc, 0x02, 0x3b), + }, + { + .uuid = "0cb4ddff-a545-4401-9d06-688af53e7f84", + .le = GUID_INIT(0x0cb4ddff, 0xa545, 0x4401, 0x9d, 0x06, 0x68, 0x8a, 0xf5, 0x3e, 0x7f, 0x84), + .be = UUID_INIT(0x0cb4ddff, 0xa545, 0x4401, 0x9d, 0x06, 0x68, 0x8a, 0xf5, 0x3e, 0x7f, 0x84), + }, +}; + +static const char * const test_uuid_wrong_data[] = { + "c33f4995-3701-450e-9fbf206a2e98e576 ", /* no hyphen(s) */ + "64b4371c-77c1-48f9-8221-29f054XX023b", /* invalid character(s) */ + "0cb4ddff-a545-4401-9d06-688af53e", /* not enough data */ +}; + +static void uuid_test_guid_valid(struct kunit *test) +{ + unsigned int i; + const struct test_uuid_data *data; + guid_t le; + + for (i = 0; i < ARRAY_SIZE(test_uuid_test_data); i++) { + data = &test_uuid_test_data[i]; + KUNIT_EXPECT_EQ(test, guid_parse(data->uuid, &le), 0); + KUNIT_EXPECT_TRUE(test, guid_equal(&data->le, &le)); + } +} + +static void uuid_test_uuid_valid(struct kunit *test) +{ + unsigned int i; + const struct test_uuid_data *data; + uuid_t be; + + for (i = 0; i < ARRAY_SIZE(test_uuid_test_data); i++) { + data = &test_uuid_test_data[i]; + KUNIT_EXPECT_EQ(test, uuid_parse(data->uuid, &be), 0); + KUNIT_EXPECT_TRUE(test, uuid_equal(&data->be, &be)); + } +} + +static void uuid_test_guid_invalid(struct kunit *test) +{ + unsigned int i; + const char *uuid; + guid_t le; + + for (i = 0; i < ARRAY_SIZE(test_uuid_wrong_data); i++) { + uuid = test_uuid_wrong_data[i]; + KUNIT_EXPECT_EQ(test, guid_parse(uuid, &le), -EINVAL); + } +} + +static void uuid_test_uuid_invalid(struct kunit *test) +{ + unsigned int i; + const char *uuid; + uuid_t be; + + for (i = 0; i < ARRAY_SIZE(test_uuid_wrong_data); i++) { + uuid = test_uuid_wrong_data[i]; + KUNIT_EXPECT_EQ(test, uuid_parse(uuid, &be), -EINVAL); + } +} + +/* + * RFC 4122 section 4.4 says random UUIDs/GUIDs (version 4) must have: + * - version 4 in the high nibble of the version byte, + * - variant DCE 1.1 (binary 10x) in the high bits of byte 8. + * + * The version byte is byte 6 in the "wire" uuid_t layout and byte 7 in + * the byte-swapped guid_t layout. + */ +static void uuid_test_uuid_gen(struct kunit *test) +{ + uuid_t u; + + for (unsigned int i = 0; i < 8; i++) { + uuid_gen(&u); + KUNIT_EXPECT_EQ(test, u.b[6] & 0xf0, 0x40); + KUNIT_EXPECT_EQ(test, u.b[8] & 0xc0, 0x80); + } +} + +static void uuid_test_guid_gen(struct kunit *test) +{ + guid_t g; + + for (unsigned int i = 0; i < 8; i++) { + guid_gen(&g); + KUNIT_EXPECT_EQ(test, g.b[7] & 0xf0, 0x40); + KUNIT_EXPECT_EQ(test, g.b[8] & 0xc0, 0x80); + } +} + +static void uuid_test_generate_random_uuid(struct kunit *test) +{ + unsigned char buf[16]; + + for (unsigned int i = 0; i < 8; i++) { + generate_random_uuid(buf); + KUNIT_EXPECT_EQ(test, buf[6] & 0xf0, 0x40); + KUNIT_EXPECT_EQ(test, buf[8] & 0xc0, 0x80); + } +} + +static void uuid_test_generate_random_guid(struct kunit *test) +{ + unsigned char buf[16]; + + for (unsigned int i = 0; i < 8; i++) { + generate_random_guid(buf); + KUNIT_EXPECT_EQ(test, buf[7] & 0xf0, 0x40); + KUNIT_EXPECT_EQ(test, buf[8] & 0xc0, 0x80); + } +} + +static struct kunit_case uuid_test_cases[] = { + KUNIT_CASE(uuid_test_guid_valid), + KUNIT_CASE(uuid_test_uuid_valid), + KUNIT_CASE(uuid_test_guid_invalid), + KUNIT_CASE(uuid_test_uuid_invalid), + KUNIT_CASE(uuid_test_uuid_gen), + KUNIT_CASE(uuid_test_guid_gen), + KUNIT_CASE(uuid_test_generate_random_uuid), + KUNIT_CASE(uuid_test_generate_random_guid), + {}, +}; + +static struct kunit_suite uuid_test_suite = { + .name = "uuid", + .test_cases = uuid_test_cases, +}; + +kunit_test_suite(uuid_test_suite); + +MODULE_AUTHOR("Andy Shevchenko "); +MODULE_DESCRIPTION("Test cases for lib/uuid.c module"); +MODULE_LICENSE("Dual BSD/GPL"); -- cgit v1.3.1