From 8167c1f071426706c233e93ecfd13aba7d5c06c8 Mon Sep 17 00:00:00 2001 From: Rosen Penev Date: Sun, 27 Sep 2026 13:35:01 -0700 Subject: tty: serial: mpc52xx_uart: move static declarations up. Avoid a compilation error so that they're not used before being declared. Fixes: 4d105880666a ("tty: serial: mpc52xx_uart: add bounds check for psc_num array index") Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202609260356.tJWbd1WU-lkp@intel.com/ Signed-off-by: Rosen Penev Link: https://patch.msgid.link/20260927203501.14105-1-rosenp@gmail.com Signed-off-by: Greg Kroah-Hartman --- lib/tests/string_kunit.c | 924 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 924 insertions(+) create mode 100644 lib/tests/string_kunit.c (limited to 'lib/tests/string_kunit.c') diff --git a/lib/tests/string_kunit.c b/lib/tests/string_kunit.c new file mode 100644 index 000000000..0819ace5b --- /dev/null +++ b/lib/tests/string_kunit.c @@ -0,0 +1,924 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Test cases for string functions. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define STRCMP_LARGE_BUF_LEN 2048 +#define STRCMP_CHANGE_POINT 1337 +#define STRCMP_TEST_EXPECT_EQUAL(test, fn, ...) KUNIT_EXPECT_EQ(test, fn(__VA_ARGS__), 0) +#define STRCMP_TEST_EXPECT_LOWER(test, fn, ...) KUNIT_EXPECT_LT(test, fn(__VA_ARGS__), 0) +#define STRCMP_TEST_EXPECT_GREATER(test, fn, ...) KUNIT_EXPECT_GT(test, fn(__VA_ARGS__), 0) + +#define STRING_TEST_MAX_LEN 128 +#define STRING_TEST_MAX_OFFSET 16 + +#define STRING_BENCH_SEED 888 +#define STRING_BENCH_WORKLOAD (1 * MEGA) + +static void string_test_memset16(struct kunit *test) +{ + unsigned i, j, k; + u16 v, *p; + + p = kunit_kzalloc(test, 256 * 2 * 2, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p); + + for (i = 0; i < 256; i++) { + for (j = 0; j < 256; j++) { + memset(p, 0xa1, 256 * 2 * sizeof(v)); + memset16(p + i, 0xb1b2, j); + for (k = 0; k < 512; k++) { + v = p[k]; + if (k < i) { + KUNIT_ASSERT_EQ_MSG(test, v, 0xa1a1, + "i:%d j:%d k:%d", i, j, k); + } else if (k < i + j) { + KUNIT_ASSERT_EQ_MSG(test, v, 0xb1b2, + "i:%d j:%d k:%d", i, j, k); + } else { + KUNIT_ASSERT_EQ_MSG(test, v, 0xa1a1, + "i:%d j:%d k:%d", i, j, k); + } + } + } + } +} + +static void string_test_memset32(struct kunit *test) +{ + unsigned i, j, k; + u32 v, *p; + + p = kunit_kzalloc(test, 256 * 2 * 4, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p); + + for (i = 0; i < 256; i++) { + for (j = 0; j < 256; j++) { + memset(p, 0xa1, 256 * 2 * sizeof(v)); + memset32(p + i, 0xb1b2b3b4, j); + for (k = 0; k < 512; k++) { + v = p[k]; + if (k < i) { + KUNIT_ASSERT_EQ_MSG(test, v, 0xa1a1a1a1, + "i:%d j:%d k:%d", i, j, k); + } else if (k < i + j) { + KUNIT_ASSERT_EQ_MSG(test, v, 0xb1b2b3b4, + "i:%d j:%d k:%d", i, j, k); + } else { + KUNIT_ASSERT_EQ_MSG(test, v, 0xa1a1a1a1, + "i:%d j:%d k:%d", i, j, k); + } + } + } + } +} + +static void string_test_memset64(struct kunit *test) +{ + unsigned i, j, k; + u64 v, *p; + + p = kunit_kzalloc(test, 256 * 2 * 8, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p); + + for (i = 0; i < 256; i++) { + for (j = 0; j < 256; j++) { + memset(p, 0xa1, 256 * 2 * sizeof(v)); + memset64(p + i, 0xb1b2b3b4b5b6b7b8ULL, j); + for (k = 0; k < 512; k++) { + v = p[k]; + if (k < i) { + KUNIT_ASSERT_EQ_MSG(test, v, 0xa1a1a1a1a1a1a1a1ULL, + "i:%d j:%d k:%d", i, j, k); + } else if (k < i + j) { + KUNIT_ASSERT_EQ_MSG(test, v, 0xb1b2b3b4b5b6b7b8ULL, + "i:%d j:%d k:%d", i, j, k); + } else { + KUNIT_ASSERT_EQ_MSG(test, v, 0xa1a1a1a1a1a1a1a1ULL, + "i:%d j:%d k:%d", i, j, k); + } + } + } + } +} + +static void string_test_strlen(struct kunit *test) +{ + size_t buf_size; + char *buf, *s; + + buf_size = PAGE_ALIGN(STRING_TEST_MAX_LEN + STRING_TEST_MAX_OFFSET + 1); + buf = vmalloc(buf_size); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buf); + + memset(buf, 'A', buf_size); + + for (size_t offset = 0; offset < STRING_TEST_MAX_OFFSET; offset++) { + for (size_t len = 0; len <= STRING_TEST_MAX_LEN; len++) { + s = buf + buf_size - 1 - offset - len; + s[len] = '\0'; + KUNIT_EXPECT_EQ_MSG(test, strlen(s), len, + "offset:%zu len:%zu", offset, len); + s[len] = 'A'; + } + } + + vfree(buf); +} + +static void string_test_strnlen(struct kunit *test) +{ + size_t buf_size; + char *buf, *s; + + buf_size = PAGE_ALIGN(STRING_TEST_MAX_LEN + STRING_TEST_MAX_OFFSET + 1); + buf = vmalloc(buf_size); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buf); + + memset(buf, 'A', buf_size); + + for (size_t offset = 0; offset < STRING_TEST_MAX_OFFSET; offset++) { + for (size_t len = 0; len <= STRING_TEST_MAX_LEN; len++) { + s = buf + buf_size - 1 - offset - len; + s[len] = '\0'; + + if (len > 0) + KUNIT_EXPECT_EQ(test, strnlen(s, len - 1), len - 1); + if (len > 1) + KUNIT_EXPECT_EQ(test, strnlen(s, len - 2), len - 2); + + KUNIT_EXPECT_EQ(test, strnlen(s, len), len); + + KUNIT_EXPECT_EQ(test, strnlen(s, len + 1), len); + KUNIT_EXPECT_EQ(test, strnlen(s, len + 2), len); + KUNIT_EXPECT_EQ(test, strnlen(s, len + 10), len); + + s[len] = 'A'; + } + } + + vfree(buf); +} + +static void string_test_strchr(struct kunit *test) +{ + const char *test_string = "abcdefghijkl"; + const char *empty_string = ""; + char *result; + int i; + + for (i = 0; i < strlen(test_string) + 1; i++) { + result = strchr(test_string, test_string[i]); + KUNIT_ASSERT_EQ_MSG(test, result - test_string, i, + "char:%c", 'a' + i); + } + + result = strchr(empty_string, '\0'); + KUNIT_ASSERT_PTR_EQ(test, result, empty_string); + + result = strchr(empty_string, 'a'); + KUNIT_ASSERT_NULL(test, result); + + result = strchr(test_string, 'z'); + KUNIT_ASSERT_NULL(test, result); +} + +static void string_test_strrchr(struct kunit *test) +{ + size_t buf_size; + char *buf, *s; + + buf_size = PAGE_ALIGN(STRING_TEST_MAX_LEN + STRING_TEST_MAX_OFFSET + 1); + buf = vmalloc(buf_size); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buf); + + memset(buf, 'A', buf_size); + + for (size_t offset = 0; offset < STRING_TEST_MAX_OFFSET; offset++) { + for (size_t len = 0; len <= STRING_TEST_MAX_LEN; len++) { + s = buf + buf_size - 1 - offset - len; + s[len] = '\0'; + + KUNIT_EXPECT_PTR_EQ(test, strrchr(s, 'Z'), NULL); + + if (len > 0) + KUNIT_EXPECT_PTR_EQ(test, strrchr(s, 'A'), s + len - 1); + else + KUNIT_EXPECT_PTR_EQ(test, strrchr(s, 'A'), NULL); + + s[len] = 'A'; + } + } + + vfree(buf); +} + +static void string_test_strnchr(struct kunit *test) +{ + const char *test_string = "abcdefghijkl"; + const char *empty_string = ""; + char *result; + int i, j; + + for (i = 0; i < strlen(test_string) + 1; i++) { + for (j = 0; j < strlen(test_string) + 2; j++) { + result = strnchr(test_string, j, test_string[i]); + if (j <= i) { + KUNIT_ASSERT_NULL_MSG(test, result, + "char:%c i:%d j:%d", 'a' + i, i, j); + } else { + KUNIT_ASSERT_EQ_MSG(test, result - test_string, i, + "char:%c i:%d j:%d", 'a' + i, i, j); + } + } + } + + result = strnchr(empty_string, 0, '\0'); + KUNIT_ASSERT_NULL(test, result); + + result = strnchr(empty_string, 1, '\0'); + KUNIT_ASSERT_PTR_EQ(test, result, empty_string); + + result = strnchr(empty_string, 1, 'a'); + KUNIT_ASSERT_NULL(test, result); + + result = strnchr(NULL, 0, '\0'); + KUNIT_ASSERT_NULL(test, result); +} + +static void string_test_strspn(struct kunit *test) +{ + static const struct strspn_test { + const char str[16]; + const char accept[16]; + const char reject[16]; + unsigned a; + unsigned r; + } tests[] = { + { "foobar", "", "", 0, 6 }, + { "abba", "abc", "ABBA", 4, 4 }, + { "abba", "a", "b", 1, 1 }, + { "", "abc", "abc", 0, 0}, + }; + const struct strspn_test *s = tests; + size_t i; + + for (i = 0; i < ARRAY_SIZE(tests); ++i, ++s) { + KUNIT_ASSERT_EQ_MSG(test, s->a, strspn(s->str, s->accept), + "i:%zu", i); + KUNIT_ASSERT_EQ_MSG(test, s->r, strcspn(s->str, s->reject), + "i:%zu", i); + } +} + +static char strcmp_buffer1[STRCMP_LARGE_BUF_LEN]; +static char strcmp_buffer2[STRCMP_LARGE_BUF_LEN]; + +static void strcmp_fill_buffers(char fill1, char fill2) +{ + memset(strcmp_buffer1, fill1, STRCMP_LARGE_BUF_LEN); + memset(strcmp_buffer2, fill2, STRCMP_LARGE_BUF_LEN); + strcmp_buffer1[STRCMP_LARGE_BUF_LEN - 1] = 0; + strcmp_buffer2[STRCMP_LARGE_BUF_LEN - 1] = 0; +} + +static void string_test_strcmp(struct kunit *test) +{ + /* Equal strings */ + STRCMP_TEST_EXPECT_EQUAL(test, strcmp, "Hello, Kernel!", "Hello, Kernel!"); + /* First string is lexicographically less than the second */ + STRCMP_TEST_EXPECT_LOWER(test, strcmp, "Hello, KUnit!", "Hello, Kernel!"); + /* First string is lexicographically larger than the second */ + STRCMP_TEST_EXPECT_GREATER(test, strcmp, "Hello, Kernel!", "Hello, KUnit!"); + /* Empty string is always lexicographically less than any non-empty string */ + STRCMP_TEST_EXPECT_LOWER(test, strcmp, "", "Non-empty string"); + /* Two empty strings should be equal */ + STRCMP_TEST_EXPECT_EQUAL(test, strcmp, "", ""); + /* Compare two strings which have only one char difference */ + STRCMP_TEST_EXPECT_LOWER(test, strcmp, "Abacaba", "Abadaba"); + /* Compare two strings which have the same prefix*/ + STRCMP_TEST_EXPECT_LOWER(test, strcmp, "Just a string", "Just a string and something else"); +} + +static void string_test_strcmp_long_strings(struct kunit *test) +{ + strcmp_fill_buffers('B', 'B'); + STRCMP_TEST_EXPECT_EQUAL(test, strcmp, strcmp_buffer1, strcmp_buffer2); + + strcmp_buffer1[STRCMP_CHANGE_POINT] = 'A'; + STRCMP_TEST_EXPECT_LOWER(test, strcmp, strcmp_buffer1, strcmp_buffer2); + + strcmp_buffer1[STRCMP_CHANGE_POINT] = 'C'; + STRCMP_TEST_EXPECT_GREATER(test, strcmp, strcmp_buffer1, strcmp_buffer2); +} + +static void string_test_strncmp(struct kunit *test) +{ + /* Equal strings */ + STRCMP_TEST_EXPECT_EQUAL(test, strncmp, "Hello, KUnit!", "Hello, KUnit!", 13); + /* First string is lexicographically less than the second */ + STRCMP_TEST_EXPECT_LOWER(test, strncmp, "Hello, KUnit!", "Hello, Kernel!", 13); + /* Result is always 'equal' when count = 0 */ + STRCMP_TEST_EXPECT_EQUAL(test, strncmp, "Hello, Kernel!", "Hello, KUnit!", 0); + /* Strings with common prefix are equal if count = length of prefix */ + STRCMP_TEST_EXPECT_EQUAL(test, strncmp, "Abacaba", "Abadaba", 3); + /* Strings with common prefix are not equal when count = length of prefix + 1 */ + STRCMP_TEST_EXPECT_LOWER(test, strncmp, "Abacaba", "Abadaba", 4); + /* If one string is a prefix of another, the shorter string is lexicographically smaller */ + STRCMP_TEST_EXPECT_LOWER(test, strncmp, "Just a string", "Just a string and something else", + strlen("Just a string and something else")); + /* + * If one string is a prefix of another, and we check first length + * of prefix chars, the result is 'equal' + */ + STRCMP_TEST_EXPECT_EQUAL(test, strncmp, "Just a string", "Just a string and something else", + strlen("Just a string")); +} + +static void string_test_strncmp_long_strings(struct kunit *test) +{ + strcmp_fill_buffers('B', 'B'); + STRCMP_TEST_EXPECT_EQUAL(test, strncmp, strcmp_buffer1, + strcmp_buffer2, STRCMP_LARGE_BUF_LEN); + + strcmp_buffer1[STRCMP_CHANGE_POINT] = 'A'; + STRCMP_TEST_EXPECT_LOWER(test, strncmp, strcmp_buffer1, + strcmp_buffer2, STRCMP_LARGE_BUF_LEN); + + strcmp_buffer1[STRCMP_CHANGE_POINT] = 'C'; + STRCMP_TEST_EXPECT_GREATER(test, strncmp, strcmp_buffer1, + strcmp_buffer2, STRCMP_LARGE_BUF_LEN); + /* the strings are equal up to STRCMP_CHANGE_POINT */ + STRCMP_TEST_EXPECT_EQUAL(test, strncmp, strcmp_buffer1, + strcmp_buffer2, STRCMP_CHANGE_POINT); + STRCMP_TEST_EXPECT_GREATER(test, strncmp, strcmp_buffer1, + strcmp_buffer2, STRCMP_CHANGE_POINT + 1); +} + +static void string_test_strcasecmp(struct kunit *test) +{ + /* Same strings in different case should be equal */ + STRCMP_TEST_EXPECT_EQUAL(test, strcasecmp, "Hello, Kernel!", "HeLLO, KErNeL!"); + /* Empty strings should be equal */ + STRCMP_TEST_EXPECT_EQUAL(test, strcasecmp, "", ""); + /* Despite ascii code for 'a' is larger than ascii code for 'B', 'a' < 'B' */ + STRCMP_TEST_EXPECT_LOWER(test, strcasecmp, "a", "B"); + STRCMP_TEST_EXPECT_GREATER(test, strcasecmp, "B", "a"); + /* Special symbols and numbers should be processed correctly */ + STRCMP_TEST_EXPECT_EQUAL(test, strcasecmp, "-+**.1230ghTTT~^", "-+**.1230Ghttt~^"); +} + +static void string_test_strcasecmp_long_strings(struct kunit *test) +{ + strcmp_fill_buffers('b', 'B'); + STRCMP_TEST_EXPECT_EQUAL(test, strcasecmp, strcmp_buffer1, strcmp_buffer2); + + strcmp_buffer1[STRCMP_CHANGE_POINT] = 'a'; + STRCMP_TEST_EXPECT_LOWER(test, strcasecmp, strcmp_buffer1, strcmp_buffer2); + + strcmp_buffer1[STRCMP_CHANGE_POINT] = 'C'; + STRCMP_TEST_EXPECT_GREATER(test, strcasecmp, strcmp_buffer1, strcmp_buffer2); +} + +static void string_test_strncasecmp(struct kunit *test) +{ + /* Same strings in different case should be equal */ + STRCMP_TEST_EXPECT_EQUAL(test, strncasecmp, "AbAcAbA", "Abacaba", strlen("Abacaba")); + /* strncasecmp should check 'count' chars only */ + STRCMP_TEST_EXPECT_EQUAL(test, strncasecmp, "AbaCaBa", "abaCaDa", 5); + STRCMP_TEST_EXPECT_LOWER(test, strncasecmp, "a", "B", 1); + STRCMP_TEST_EXPECT_GREATER(test, strncasecmp, "B", "a", 1); + /* Result is always 'equal' when count = 0 */ + STRCMP_TEST_EXPECT_EQUAL(test, strncasecmp, "Abacaba", "Not abacaba", 0); +} + +static void string_test_strncasecmp_long_strings(struct kunit *test) +{ + strcmp_fill_buffers('b', 'B'); + STRCMP_TEST_EXPECT_EQUAL(test, strncasecmp, strcmp_buffer1, + strcmp_buffer2, STRCMP_LARGE_BUF_LEN); + + strcmp_buffer1[STRCMP_CHANGE_POINT] = 'a'; + STRCMP_TEST_EXPECT_LOWER(test, strncasecmp, strcmp_buffer1, + strcmp_buffer2, STRCMP_LARGE_BUF_LEN); + + strcmp_buffer1[STRCMP_CHANGE_POINT] = 'C'; + STRCMP_TEST_EXPECT_GREATER(test, strncasecmp, strcmp_buffer1, + strcmp_buffer2, STRCMP_LARGE_BUF_LEN); + + STRCMP_TEST_EXPECT_EQUAL(test, strncasecmp, strcmp_buffer1, + strcmp_buffer2, STRCMP_CHANGE_POINT); + STRCMP_TEST_EXPECT_GREATER(test, strncasecmp, strcmp_buffer1, + strcmp_buffer2, STRCMP_CHANGE_POINT + 1); +} + +/** + * strscpy_check() - Run a specific test case. + * @test: KUnit test context pointer + * @src: Source string, argument to strscpy_pad() + * @count: Size of destination buffer, argument to strscpy_pad() + * @expected: Expected return value from call to strscpy_pad() + * @chars: Number of characters from the src string expected to be + * written to the dst buffer. + * @terminator: 1 if there should be a terminating null byte 0 otherwise. + * @pad: Number of pad characters expected (in the tail of dst buffer). + * (@pad does not include the null terminator byte.) + * + * Calls strscpy_pad() and verifies the return value and state of the + * destination buffer after the call returns. + */ +static void strscpy_check(struct kunit *test, char *src, int count, + int expected, int chars, int terminator, int pad) +{ + int nr_bytes_poison; + int max_expected; + int max_count; + int written; + char buf[6]; + int index, i; + const char POISON = 'z'; + + KUNIT_ASSERT_TRUE_MSG(test, src != NULL, + "null source string not supported"); + + memset(buf, POISON, sizeof(buf)); + /* Future proofing test suite, validate args */ + max_count = sizeof(buf) - 2; /* Space for null and to verify overflow */ + max_expected = count - 1; /* Space for the null */ + + KUNIT_ASSERT_LE_MSG(test, count, max_count, + "count (%d) is too big (%d) ... aborting", count, max_count); + KUNIT_EXPECT_LE_MSG(test, expected, max_expected, + "expected (%d) is bigger than can possibly be returned (%d)", + expected, max_expected); + + written = strscpy_pad(buf, src, count); + KUNIT_ASSERT_EQ(test, written, expected); + + if (count && written == -E2BIG) { + KUNIT_ASSERT_EQ_MSG(test, 0, strncmp(buf, src, count - 1), + "buffer state invalid for -E2BIG"); + KUNIT_ASSERT_EQ_MSG(test, buf[count - 1], '\0', + "too big string is not null terminated correctly"); + } + + for (i = 0; i < chars; i++) + KUNIT_ASSERT_EQ_MSG(test, buf[i], src[i], + "buf[i]==%c != src[i]==%c", buf[i], src[i]); + + if (terminator) + KUNIT_ASSERT_EQ_MSG(test, buf[count - 1], '\0', + "string is not null terminated correctly"); + + for (i = 0; i < pad; i++) { + index = chars + terminator + i; + KUNIT_ASSERT_EQ_MSG(test, buf[index], '\0', + "padding missing at index: %d", i); + } + + nr_bytes_poison = sizeof(buf) - chars - terminator - pad; + for (i = 0; i < nr_bytes_poison; i++) { + index = sizeof(buf) - 1 - i; /* Check from the end back */ + KUNIT_ASSERT_EQ_MSG(test, buf[index], POISON, + "poison value missing at index: %d", i); + } +} + +static void string_test_strscpy(struct kunit *test) +{ + char dest[8]; + + /* + * strscpy_check() uses a destination buffer of size 6 and needs at + * least 2 characters spare (one for null and one to check for + * overflow). This means we should only call tc() with + * strings up to a maximum of 4 characters long and 'count' + * should not exceed 4. To test with longer strings increase + * the buffer size in tc(). + */ + + /* strscpy_check(test, src, count, expected, chars, terminator, pad) */ + strscpy_check(test, "a", 0, -E2BIG, 0, 0, 0); + strscpy_check(test, "", 0, -E2BIG, 0, 0, 0); + + strscpy_check(test, "a", 1, -E2BIG, 0, 1, 0); + strscpy_check(test, "", 1, 0, 0, 1, 0); + + strscpy_check(test, "ab", 2, -E2BIG, 1, 1, 0); + strscpy_check(test, "a", 2, 1, 1, 1, 0); + strscpy_check(test, "", 2, 0, 0, 1, 1); + + strscpy_check(test, "abc", 3, -E2BIG, 2, 1, 0); + strscpy_check(test, "ab", 3, 2, 2, 1, 0); + strscpy_check(test, "a", 3, 1, 1, 1, 1); + strscpy_check(test, "", 3, 0, 0, 1, 2); + + strscpy_check(test, "abcd", 4, -E2BIG, 3, 1, 0); + strscpy_check(test, "abc", 4, 3, 3, 1, 0); + strscpy_check(test, "ab", 4, 2, 2, 1, 1); + strscpy_check(test, "a", 4, 1, 1, 1, 2); + strscpy_check(test, "", 4, 0, 0, 1, 3); + + /* Compile-time-known source strings. */ + KUNIT_EXPECT_EQ(test, strscpy(dest, "", ARRAY_SIZE(dest)), 0); + KUNIT_EXPECT_EQ(test, strscpy(dest, "", 3), 0); + KUNIT_EXPECT_EQ(test, strscpy(dest, "", 1), 0); + KUNIT_EXPECT_EQ(test, strscpy(dest, "", 0), -E2BIG); + KUNIT_EXPECT_EQ(test, strscpy(dest, "Fixed", ARRAY_SIZE(dest)), 5); + KUNIT_EXPECT_EQ(test, strscpy(dest, "Fixed", 3), -E2BIG); + KUNIT_EXPECT_EQ(test, strscpy(dest, "Fixed", 1), -E2BIG); + KUNIT_EXPECT_EQ(test, strscpy(dest, "Fixed", 0), -E2BIG); + KUNIT_EXPECT_EQ(test, strscpy(dest, "This is too long", ARRAY_SIZE(dest)), -E2BIG); +} + +static volatile int unconst; + +static void string_test_strcat(struct kunit *test) +{ + char dest[8]; + + /* Destination is terminated. */ + memset(dest, 0, sizeof(dest)); + KUNIT_EXPECT_EQ(test, strlen(dest), 0); + /* Empty copy does nothing. */ + KUNIT_EXPECT_TRUE(test, strcat(dest, "") == dest); + KUNIT_EXPECT_STREQ(test, dest, ""); + /* 4 characters copied in, stops at %NUL. */ + KUNIT_EXPECT_TRUE(test, strcat(dest, "four\000123") == dest); + KUNIT_EXPECT_STREQ(test, dest, "four"); + KUNIT_EXPECT_EQ(test, dest[5], '\0'); + /* 2 more characters copied in okay. */ + KUNIT_EXPECT_TRUE(test, strcat(dest, "AB") == dest); + KUNIT_EXPECT_STREQ(test, dest, "fourAB"); +} + +static void string_test_strncat(struct kunit *test) +{ + char dest[8]; + + /* Destination is terminated. */ + memset(dest, 0, sizeof(dest)); + KUNIT_EXPECT_EQ(test, strlen(dest), 0); + /* Empty copy of size 0 does nothing. */ + KUNIT_EXPECT_TRUE(test, strncat(dest, "", 0 + unconst) == dest); + KUNIT_EXPECT_STREQ(test, dest, ""); + /* Empty copy of size 1 does nothing too. */ + KUNIT_EXPECT_TRUE(test, strncat(dest, "", 1 + unconst) == dest); + KUNIT_EXPECT_STREQ(test, dest, ""); + /* Copy of max 0 characters should do nothing. */ + KUNIT_EXPECT_TRUE(test, strncat(dest, "asdf", 0 + unconst) == dest); + KUNIT_EXPECT_STREQ(test, dest, ""); + + /* 4 characters copied in, even if max is 8. */ + KUNIT_EXPECT_TRUE(test, strncat(dest, "four\000123", 8 + unconst) == dest); + KUNIT_EXPECT_STREQ(test, dest, "four"); + KUNIT_EXPECT_EQ(test, dest[5], '\0'); + KUNIT_EXPECT_EQ(test, dest[6], '\0'); + /* 2 characters copied in okay, 2 ignored. */ + KUNIT_EXPECT_TRUE(test, strncat(dest, "ABCD", 2 + unconst) == dest); + KUNIT_EXPECT_STREQ(test, dest, "fourAB"); +} + +static void string_test_strlcat(struct kunit *test) +{ + char dest[8] = ""; + int len = sizeof(dest) + unconst; + + /* Destination is terminated. */ + KUNIT_EXPECT_EQ(test, strlen(dest), 0); + /* Empty copy is size 0. */ + KUNIT_EXPECT_EQ(test, strlcat(dest, "", len), 0); + KUNIT_EXPECT_STREQ(test, dest, ""); + /* Size 1 should keep buffer terminated, report size of source only. */ + KUNIT_EXPECT_EQ(test, strlcat(dest, "four", 1 + unconst), 4); + KUNIT_EXPECT_STREQ(test, dest, ""); + + /* 4 characters copied in. */ + KUNIT_EXPECT_EQ(test, strlcat(dest, "four", len), 4); + KUNIT_EXPECT_STREQ(test, dest, "four"); + /* 2 characters copied in okay, gets to 6 total. */ + KUNIT_EXPECT_EQ(test, strlcat(dest, "AB", len), 6); + KUNIT_EXPECT_STREQ(test, dest, "fourAB"); + /* 2 characters ignored if max size (7) reached. */ + KUNIT_EXPECT_EQ(test, strlcat(dest, "CD", 7 + unconst), 8); + KUNIT_EXPECT_STREQ(test, dest, "fourAB"); + /* 1 of 2 characters skipped, now at true max size. */ + KUNIT_EXPECT_EQ(test, strlcat(dest, "EFG", len), 9); + KUNIT_EXPECT_STREQ(test, dest, "fourABE"); + /* Everything else ignored, now at full size. */ + KUNIT_EXPECT_EQ(test, strlcat(dest, "1234", len), 11); + KUNIT_EXPECT_STREQ(test, dest, "fourABE"); +} + +static void string_test_strtomem(struct kunit *test) +{ + static const char input[sizeof(unsigned long)] = "hi"; + static const char truncate[] = "this is too long"; + struct { + unsigned long canary1; + unsigned char output[sizeof(unsigned long)] __nonstring; + unsigned long canary2; + } wrap; + + memset(&wrap, 0xFF, sizeof(wrap)); + KUNIT_EXPECT_EQ_MSG(test, wrap.canary1, ULONG_MAX, + "bad initial canary value"); + KUNIT_EXPECT_EQ_MSG(test, wrap.canary2, ULONG_MAX, + "bad initial canary value"); + + /* Check unpadded copy leaves surroundings untouched. */ + strtomem(wrap.output, input); + KUNIT_EXPECT_EQ(test, wrap.canary1, ULONG_MAX); + KUNIT_EXPECT_EQ(test, wrap.output[0], input[0]); + KUNIT_EXPECT_EQ(test, wrap.output[1], input[1]); + for (size_t i = 2; i < sizeof(wrap.output); i++) + KUNIT_EXPECT_EQ(test, wrap.output[i], 0xFF); + KUNIT_EXPECT_EQ(test, wrap.canary2, ULONG_MAX); + + /* Check truncated copy leaves surroundings untouched. */ + memset(&wrap, 0xFF, sizeof(wrap)); + strtomem(wrap.output, truncate); + KUNIT_EXPECT_EQ(test, wrap.canary1, ULONG_MAX); + for (size_t i = 0; i < sizeof(wrap.output); i++) + KUNIT_EXPECT_EQ(test, wrap.output[i], truncate[i]); + KUNIT_EXPECT_EQ(test, wrap.canary2, ULONG_MAX); + + /* Check padded copy leaves only string padded. */ + memset(&wrap, 0xFF, sizeof(wrap)); + strtomem_pad(wrap.output, input, 0xAA); + KUNIT_EXPECT_EQ(test, wrap.canary1, ULONG_MAX); + KUNIT_EXPECT_EQ(test, wrap.output[0], input[0]); + KUNIT_EXPECT_EQ(test, wrap.output[1], input[1]); + for (size_t i = 2; i < sizeof(wrap.output); i++) + KUNIT_EXPECT_EQ(test, wrap.output[i], 0xAA); + KUNIT_EXPECT_EQ(test, wrap.canary2, ULONG_MAX); + + /* Check truncated padded copy has no padding. */ + memset(&wrap, 0xFF, sizeof(wrap)); + strtomem(wrap.output, truncate); + KUNIT_EXPECT_EQ(test, wrap.canary1, ULONG_MAX); + for (size_t i = 0; i < sizeof(wrap.output); i++) + KUNIT_EXPECT_EQ(test, wrap.output[i], truncate[i]); + KUNIT_EXPECT_EQ(test, wrap.canary2, ULONG_MAX); +} + + +static void string_test_memtostr(struct kunit *test) +{ + char nonstring[7] __nonstring = { 'a', 'b', 'c', 'd', 'e', 'f', 'g' }; + char nonstring_small[3] __nonstring = { 'a', 'b', 'c' }; + char dest[sizeof(nonstring) + 1]; + + /* Copy in a non-NUL-terminated string into exactly right-sized dest. */ + KUNIT_EXPECT_EQ(test, sizeof(dest), sizeof(nonstring) + 1); + memset(dest, 'X', sizeof(dest)); + memtostr(dest, nonstring); + KUNIT_EXPECT_STREQ(test, dest, "abcdefg"); + memset(dest, 'X', sizeof(dest)); + memtostr(dest, nonstring_small); + KUNIT_EXPECT_STREQ(test, dest, "abc"); + KUNIT_EXPECT_EQ(test, dest[7], 'X'); + + memset(dest, 'X', sizeof(dest)); + memtostr_pad(dest, nonstring); + KUNIT_EXPECT_STREQ(test, dest, "abcdefg"); + memset(dest, 'X', sizeof(dest)); + memtostr_pad(dest, nonstring_small); + KUNIT_EXPECT_STREQ(test, dest, "abc"); + KUNIT_EXPECT_EQ(test, dest[7], '\0'); +} + +static void string_test_strends(struct kunit *test) +{ + KUNIT_EXPECT_TRUE(test, strends("foo-bar", "bar")); + KUNIT_EXPECT_TRUE(test, strends("foo-bar", "-bar")); + KUNIT_EXPECT_TRUE(test, strends("foobar", "foobar")); + KUNIT_EXPECT_TRUE(test, strends("foobar", "")); + KUNIT_EXPECT_FALSE(test, strends("bar", "foobar")); + KUNIT_EXPECT_FALSE(test, strends("", "foo")); + KUNIT_EXPECT_FALSE(test, strends("foobar", "ba")); + KUNIT_EXPECT_TRUE(test, strends("", "")); +} + +#if IS_ENABLED(CONFIG_STRING_KUNIT_BENCH) +/* Target string lengths for benchmarking */ +static const size_t bench_lens[] = { + 0, 1, 7, 8, 16, 31, 64, 127, 512, 1024, 3173, 4096, +}; + +/** + * alloc_max_bench_buffer() - Allocate buffer for the max test case. + * @test: KUnit context for managed allocation. + * @lens: Array of lengths used in the benchmark cases. + * @count: Number of elements in the @lens array. + * @buf_len: [out] Pointer to store the actually allocated buffer + * size (including NUL character). + * + * Return: Pointer to the allocated memory, or NULL on failure. + */ +static void *alloc_max_bench_buffer(struct kunit *test, const size_t *lens, + size_t count, size_t *buf_len) +{ + size_t max_len = 0; + void *buf; + + for (size_t i = 0; i < count; i++) + max_len = max(lens[i], max_len); + + /* Add space for NUL character */ + max_len += 1; + + buf = kunit_kzalloc(test, max_len, GFP_KERNEL); + if (!buf) + return NULL; + + if (buf_len) + *buf_len = max_len; + + return buf; +} + +/** + * fill_random_string() - Populate a buffer with a random NUL-terminated string. + * @buf: Buffer to fill. + * @len: Length of the buffer in bytes. + * + * Fills the buffer with random non-NUL bytes and ensures the string is + * properly NUL-terminated. + */ +static void fill_random_string(char *buf, size_t len) +{ + struct rnd_state state; + + if (!buf || !len) + return; + + /* Use a fixed seed to ensure deterministic benchmark results */ + prandom_seed_state(&state, STRING_BENCH_SEED); + prandom_bytes_state(&state, buf, len); + + /* Replace NUL characters to avoid early string termination */ + for (size_t i = 0; i < len; i++) { + if (buf[i] == '\0') + buf[i] = 0x01; + } + + buf[len - 1] = '\0'; +} + +/** + * STRING_BENCH() - Benchmark string functions. + * @iters: Number of iterations to run. + * @func: Function to benchmark. + * @...: Variable arguments passed to @func. + * + * Disables preemption and measures the total time in nanoseconds to execute + * @func(@__VA_ARGS__) for @iters times, including a small warm-up phase. + * + * Context: Disables preemption during measurement. + * Return: Total execution time in nanoseconds (u64). + */ +#define STRING_BENCH(iters, func, ...) \ +({ \ + /* Volatile function pointer prevents dead code elimination */ \ + typeof(func) (* volatile __func) = (func); \ + size_t __bn_iters = (iters); \ + size_t __bn_warm_iters; \ + u64 __bn_t; \ + \ + /* Use 10% of the given iterations (maximum 50) to warm up */ \ + __bn_warm_iters = max(__bn_iters / 10, 50U); \ + \ + for (size_t __bn_i = 0; __bn_i < __bn_warm_iters; __bn_i++) \ + (void)__func(__VA_ARGS__); \ + \ + preempt_disable(); \ + __bn_t = ktime_get_ns(); \ + for (size_t __bn_i = 0; __bn_i < __bn_iters; __bn_i++) \ + (void)__func(__VA_ARGS__); \ + __bn_t = ktime_get_ns() - __bn_t; \ + preempt_enable(); \ + __bn_t; \ +}) + +/** + * STRING_BENCH_BUF() - Benchmark harness for single-buffer functions. + * @test: KUnit context. + * @buf_name: Local char * variable name to be defined. + * @buf_size: Local size_t variable name to be defined. + * @func: Function to benchmark. + * @...: Extra arguments for @func. + * + * Prepares a randomized, NUL-terminated buffer and iterates through lengths + * in bench_lens, defining @buf_name and @buf_size in each loop. + */ +#define STRING_BENCH_BUF(test, buf_name, buf_size, func, ...) \ +do { \ + size_t _bn_i, _bn_iters, _bn_size = 0; \ + u64 _bn_t, _bn_mbps = 0, _bn_lat = 0; \ + char *_bn_buf; \ + \ + _bn_buf = alloc_max_bench_buffer(test, bench_lens, \ + ARRAY_SIZE(bench_lens), &_bn_size); \ + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, _bn_buf); \ + \ + fill_random_string(_bn_buf, _bn_size); \ + \ + for (_bn_i = 0; _bn_i < ARRAY_SIZE(bench_lens); _bn_i++) { \ + size_t buf_size = bench_lens[_bn_i]; \ + char *buf_name = _bn_buf + _bn_size - buf_size - 1; \ + _bn_iters = STRING_BENCH_WORKLOAD / max(buf_size, 1U); \ + \ + _bn_t = STRING_BENCH(_bn_iters, func, ##__VA_ARGS__); \ + if (_bn_t > 0) { \ + _bn_mbps = (u64)(buf_size) * _bn_iters * \ + (NSEC_PER_SEC / MEGA); \ + _bn_mbps = div64_u64(_bn_mbps, _bn_t); \ + _bn_lat = div64_u64(_bn_t, _bn_iters); \ + } \ + kunit_info(test, "len=%zu: %llu MB/s (%llu ns/call)\n", \ + buf_size, _bn_mbps, _bn_lat); \ + } \ +} while (0) +#else +#define STRING_BENCH_BUF(test, buf_name, buf_size, func, ...) \ + kunit_skip(test, "not enabled") +#endif /* IS_ENABLED(CONFIG_STRING_KUNIT_BENCH) */ + +static void string_bench_strlen(struct kunit *test) +{ + STRING_BENCH_BUF(test, buf, len, strlen, buf); +} + +static void string_bench_strnlen(struct kunit *test) +{ + STRING_BENCH_BUF(test, buf, len, strnlen, buf, len); +} + +static void string_bench_strchr(struct kunit *test) +{ + STRING_BENCH_BUF(test, buf, len, strchr, buf, '\0'); +} + +static void string_bench_strrchr(struct kunit *test) +{ + STRING_BENCH_BUF(test, buf, len, strrchr, buf, '\0'); +} + +static struct kunit_case string_test_cases[] = { + KUNIT_CASE(string_test_memset16), + KUNIT_CASE(string_test_memset32), + KUNIT_CASE(string_test_memset64), + KUNIT_CASE(string_test_strlen), + KUNIT_CASE(string_test_strnlen), + KUNIT_CASE(string_test_strchr), + KUNIT_CASE(string_test_strnchr), + KUNIT_CASE(string_test_strrchr), + KUNIT_CASE(string_test_strspn), + KUNIT_CASE(string_test_strcmp), + KUNIT_CASE(string_test_strcmp_long_strings), + KUNIT_CASE(string_test_strncmp), + KUNIT_CASE(string_test_strncmp_long_strings), + KUNIT_CASE(string_test_strcasecmp), + KUNIT_CASE(string_test_strcasecmp_long_strings), + KUNIT_CASE(string_test_strncasecmp), + KUNIT_CASE(string_test_strncasecmp_long_strings), + KUNIT_CASE(string_test_strscpy), + KUNIT_CASE(string_test_strcat), + KUNIT_CASE(string_test_strncat), + KUNIT_CASE(string_test_strlcat), + KUNIT_CASE(string_test_strtomem), + KUNIT_CASE(string_test_memtostr), + KUNIT_CASE(string_test_strends), + KUNIT_CASE(string_bench_strlen), + KUNIT_CASE(string_bench_strnlen), + KUNIT_CASE(string_bench_strchr), + KUNIT_CASE(string_bench_strrchr), + {} +}; + +static struct kunit_suite string_test_suite = { + .name = "string", + .test_cases = string_test_cases, +}; + +kunit_test_suites(&string_test_suite); + +MODULE_DESCRIPTION("Test cases for string functions"); +MODULE_LICENSE("GPL v2"); -- cgit v1.3.1