kstrto*: converting strings to integers done (hopefully) right

1. simple_strto*() do not contain overflow checks and crufty,
   libc way to indicate failure.
2. strict_strto*() also do not have overflow checks but the name and
   comments pretend they do.
3. Both families have only "long long" and "long" variants,
   but users want strtou8()
4. Both "simple" and "strict" prefixes are wrong:
   Simple doesn't exactly say what's so simple, strict should not exist
   because conversion should be strict by default.

The solution is to use "k" prefix and add convertors for more types.
Enter
	kstrtoull()
	kstrtoll()
	kstrtoul()
	kstrtol()
	kstrtouint()
	kstrtoint()

	kstrtou64()
	kstrtos64()
	kstrtou32()
	kstrtos32()
	kstrtou16()
	kstrtos16()
	kstrtou8()
	kstrtos8()

Include runtime testsuite (somewhat incomplete) as well.

strict_strto*() become deprecated, stubbed to kstrto*() and
eventually will be removed altogether.

Use kstrto*() in code today!

Note: on some archs _kstrtoul() and _kstrtol() are left in tree, even if
      they'll be unused at runtime. This is temporarily solution,
      because I don't want to hardcode list of archs where these
      functions aren't needed. Current solution with sizeof() and
      __alignof__ at least always works.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

5 files changed, 971 insertions, 141 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index bef5faab660f..df9234c5f9d1 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1250,3 +1250,6 @@ source "samples/Kconfig"
 source "lib/Kconfig.kgdb"
 
 source "lib/Kconfig.kmemcheck"
+
+config TEST_KSTRTOX
+	tristate "Test kstrto*() family of functions at runtime"
diff --git a/lib/Makefile b/lib/Makefile
index ef7ed71a6ffd..8c9de027ebb1 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -22,6 +22,8 @@ lib-y	+= kobject.o kref.o klist.o
 obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
 	 bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \
 	 string_helpers.o gcd.o lcm.o list_sort.o uuid.o flex_array.o
+obj-y += kstrtox.o
+obj-$(CONFIG_TEST_KSTRTOX) += test-kstrtox.o
 
 ifeq ($(CONFIG_DEBUG_KOBJECT),y)
 CFLAGS_kobject.o += -DDEBUG
diff --git a/lib/kstrtox.c b/lib/kstrtox.c
new file mode 100644
index 000000000000..05672e819f8c
--- /dev/null
+++ b/lib/kstrtox.c
@@ -0,0 +1,227 @@
+/*
+ * Convert integer string representation to an integer.
+ * If an integer doesn't fit into specified type, -E is returned.
+ *
+ * Integer starts with optional sign.
+ * kstrtou*() functions do not accept sign "-".
+ *
+ * Radix 0 means autodetection: leading "0x" implies radix 16,
+ * leading "0" implies radix 8, otherwise radix is 10.
+ * Autodetection hints work after optional sign, but not before.
+ *
+ * If -E is returned, result is not touched.
+ */
+#include <linux/ctype.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/types.h>
+
+static inline char _tolower(const char c)
+{
+	return c | 0x20;
+}
+
+static int _kstrtoull(const char *s, unsigned int base, unsigned long long *res)
+{
+	unsigned long long acc;
+	int ok;
+
+	if (base == 0) {
+		if (s[0] == '0') {
+			if (_tolower(s[1]) == 'x' && isxdigit(s[2]))
+				base = 16;
+			else
+				base = 8;
+		} else
+			base = 10;
+	}
+	if (base == 16 && s[0] == '0' && _tolower(s[1]) == 'x')
+		s += 2;
+
+	acc = 0;
+	ok = 0;
+	while (*s) {
+		unsigned int val;
+
+		if ('0' <= *s && *s <= '9')
+			val = *s - '0';
+		else if ('a' <= _tolower(*s) && _tolower(*s) <= 'f')
+			val = _tolower(*s) - 'a' + 10;
+		else if (*s == '\n') {
+			if (*(s + 1) == '\0')
+				break;
+			else
+				return -EINVAL;
+		} else
+			return -EINVAL;
+
+		if (val >= base)
+			return -EINVAL;
+		if (acc > div_u64(ULLONG_MAX - val, base))
+			return -ERANGE;
+		acc = acc * base + val;
+		ok = 1;
+
+		s++;
+	}
+	if (!ok)
+		return -EINVAL;
+	*res = acc;
+	return 0;
+}
+
+int kstrtoull(const char *s, unsigned int base, unsigned long long *res)
+{
+	if (s[0] == '+')
+		s++;
+	return _kstrtoull(s, base, res);
+}
+EXPORT_SYMBOL(kstrtoull);
+
+int kstrtoll(const char *s, unsigned int base, long long *res)
+{
+	unsigned long long tmp;
+	int rv;
+
+	if (s[0] == '-') {
+		rv = _kstrtoull(s + 1, base, &tmp);
+		if (rv < 0)
+			return rv;
+		if ((long long)(-tmp) >= 0)
+			return -ERANGE;
+		*res = -tmp;
+	} else {
+		rv = kstrtoull(s, base, &tmp);
+		if (rv < 0)
+			return rv;
+		if ((long long)tmp < 0)
+			return -ERANGE;
+		*res = tmp;
+	}
+	return 0;
+}
+EXPORT_SYMBOL(kstrtoll);
+
+/* Internal, do not use. */
+int _kstrtoul(const char *s, unsigned int base, unsigned long *res)
+{
+	unsigned long long tmp;
+	int rv;
+
+	rv = kstrtoull(s, base, &tmp);
+	if (rv < 0)
+		return rv;
+	if (tmp != (unsigned long long)(unsigned long)tmp)
+		return -ERANGE;
+	*res = tmp;
+	return 0;
+}
+EXPORT_SYMBOL(_kstrtoul);
+
+/* Internal, do not use. */
+int _kstrtol(const char *s, unsigned int base, long *res)
+{
+	long long tmp;
+	int rv;
+
+	rv = kstrtoll(s, base, &tmp);
+	if (rv < 0)
+		return rv;
+	if (tmp != (long long)(long)tmp)
+		return -ERANGE;
+	*res = tmp;
+	return 0;
+}
+EXPORT_SYMBOL(_kstrtol);
+
+int kstrtouint(const char *s, unsigned int base, unsigned int *res)
+{
+	unsigned long long tmp;
+	int rv;
+
+	rv = kstrtoull(s, base, &tmp);
+	if (rv < 0)
+		return rv;
+	if (tmp != (unsigned long long)(unsigned int)tmp)
+		return -ERANGE;
+	*res = tmp;
+	return 0;
+}
+EXPORT_SYMBOL(kstrtouint);
+
+int kstrtoint(const char *s, unsigned int base, int *res)
+{
+	long long tmp;
+	int rv;
+
+	rv = kstrtoll(s, base, &tmp);
+	if (rv < 0)
+		return rv;
+	if (tmp != (long long)(int)tmp)
+		return -ERANGE;
+	*res = tmp;
+	return 0;
+}
+EXPORT_SYMBOL(kstrtoint);
+
+int kstrtou16(const char *s, unsigned int base, u16 *res)
+{
+	unsigned long long tmp;
+	int rv;
+
+	rv = kstrtoull(s, base, &tmp);
+	if (rv < 0)
+		return rv;
+	if (tmp != (unsigned long long)(u16)tmp)
+		return -ERANGE;
+	*res = tmp;
+	return 0;
+}
+EXPORT_SYMBOL(kstrtou16);
+
+int kstrtos16(const char *s, unsigned int base, s16 *res)
+{
+	long long tmp;
+	int rv;
+
+	rv = kstrtoll(s, base, &tmp);
+	if (rv < 0)
+		return rv;
+	if (tmp != (long long)(s16)tmp)
+		return -ERANGE;
+	*res = tmp;
+	return 0;
+}
+EXPORT_SYMBOL(kstrtos16);
+
+int kstrtou8(const char *s, unsigned int base, u8 *res)
+{
+	unsigned long long tmp;
+	int rv;
+
+	rv = kstrtoull(s, base, &tmp);
+	if (rv < 0)
+		return rv;
+	if (tmp != (unsigned long long)(u8)tmp)
+		return -ERANGE;
+	*res = tmp;
+	return 0;
+}
+EXPORT_SYMBOL(kstrtou8);
+
+int kstrtos8(const char *s, unsigned int base, s8 *res)
+{
+	long long tmp;
+	int rv;
+
+	rv = kstrtoll(s, base, &tmp);
+	if (rv < 0)
+		return rv;
+	if (tmp != (long long)(s8)tmp)
+		return -ERANGE;
+	*res = tmp;
+	return 0;
+}
+EXPORT_SYMBOL(kstrtos8);
diff --git a/lib/test-kstrtox.c b/lib/test-kstrtox.c
new file mode 100644
index 000000000000..325c2f9ecebd
--- /dev/null
+++ b/lib/test-kstrtox.c
@@ -0,0 +1,739 @@
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#define for_each_test(i, test)	\
+	for (i = 0; i < sizeof(test) / sizeof(test[0]); i++)
+
+struct test_fail {
+	const char *str;
+	unsigned int base;
+};
+
+#define DEFINE_TEST_FAIL(test)	\
+	const struct test_fail test[] __initdata
+
+#define DECLARE_TEST_OK(type, test_type)	\
+	test_type {				\
+		const char *str;		\
+		unsigned int base;		\
+		type expected_res;		\
+	}
+
+#define DEFINE_TEST_OK(type, test)	\
+	const type test[] __initdata
+
+#define TEST_FAIL(fn, type, fmt, test)					\
+{									\
+	unsigned int i;							\
+									\
+	for_each_test(i, test) {					\
+		const struct test_fail *t = &test[i];			\
+		type tmp;						\
+		int rv;							\
+									\
+		tmp = 0;						\
+		rv = fn(t->str, t->base, &tmp);				\
+		if (rv >= 0) {						\
+			WARN(1, "str '%s', base %u, expected -E, got %d/" fmt "\n",	\
+				t->str, t->base, rv, tmp);		\
+			continue;					\
+		}							\
+	}								\
+}
+
+#define TEST_OK(fn, type, fmt, test)					\
+{									\
+	unsigned int i;							\
+									\
+	for_each_test(i, test) {					\
+		const typeof(test[0]) *t = &test[i];			\
+		type res;						\
+		int rv;							\
+									\
+		rv = fn(t->str, t->base, &res);				\
+		if (rv != 0) {						\
+			WARN(1, "str '%s', base %u, expected 0/" fmt ", got %d\n",	\
+				t->str, t->base, t->expected_res, rv);	\
+			continue;					\
+		}							\
+		if (res != t->expected_res) {				\
+			WARN(1, "str '%s', base %u, expected " fmt ", got " fmt "\n",	\
+				t->str, t->base, t->expected_res, res);	\
+			continue;					\
+		}							\
+	}								\
+}
+
+static void __init test_kstrtoull_ok(void)
+{
+	DECLARE_TEST_OK(unsigned long long, struct test_ull);
+	static DEFINE_TEST_OK(struct test_ull, test_ull_ok) = {
+		{"0",	10,	0ULL},
+		{"1",	10,	1ULL},
+		{"127",	10,	127ULL},
+		{"128",	10,	128ULL},
+		{"129",	10,	129ULL},
+		{"255",	10,	255ULL},
+		{"256",	10,	256ULL},
+		{"257",	10,	257ULL},
+		{"32767",	10,	32767ULL},
+		{"32768",	10,	32768ULL},
+		{"32769",	10,	32769ULL},
+		{"65535",	10,	65535ULL},
+		{"65536",	10,	65536ULL},
+		{"65537",	10,	65537ULL},
+		{"2147483647",	10,	2147483647ULL},
+		{"2147483648",	10,	2147483648ULL},
+		{"2147483649",	10,	2147483649ULL},
+		{"4294967295",	10,	4294967295ULL},
+		{"4294967296",	10,	4294967296ULL},
+		{"4294967297",	10,	4294967297ULL},
+		{"9223372036854775807",	10,	9223372036854775807ULL},
+		{"9223372036854775808",	10,	9223372036854775808ULL},
+		{"9223372036854775809",	10,	9223372036854775809ULL},
+		{"18446744073709551614",	10,	18446744073709551614ULL},
+		{"18446744073709551615",	10,	18446744073709551615ULL},
+
+		{"00",		8,	00ULL},
+		{"01",		8,	01ULL},
+		{"0177",	8,	0177ULL},
+		{"0200",	8,	0200ULL},
+		{"0201",	8,	0201ULL},
+		{"0377",	8,	0377ULL},
+		{"0400",	8,	0400ULL},
+		{"0401",	8,	0401ULL},
+		{"077777",	8,	077777ULL},
+		{"0100000",	8,	0100000ULL},
+		{"0100001",	8,	0100001ULL},
+		{"0177777",	8,	0177777ULL},
+		{"0200000",	8,	0200000ULL},
+		{"0200001",	8,	0200001ULL},
+		{"017777777777",	8,	017777777777ULL},
+		{"020000000000",	8,	020000000000ULL},
+		{"020000000001",	8,	020000000001ULL},
+		{"037777777777",	8,	037777777777ULL},
+		{"040000000000",	8,	040000000000ULL},
+		{"040000000001",	8,	040000000001ULL},
+		{"0777777777777777777777",	8,	0777777777777777777777ULL},
+		{"01000000000000000000000",	8,	01000000000000000000000ULL},
+		{"01000000000000000000001",	8,	01000000000000000000001ULL},
+		{"01777777777777777777776",	8,	01777777777777777777776ULL},
+		{"01777777777777777777777",	8,	01777777777777777777777ULL},
+
+		{"0x0",		16,	0x0ULL},
+		{"0x1",		16,	0x1ULL},
+		{"0x7f",	16,	0x7fULL},
+		{"0x80",	16,	0x80ULL},
+		{"0x81",	16,	0x81ULL},
+		{"0xff",	16,	0xffULL},
+		{"0x100",	16,	0x100ULL},
+		{"0x101",	16,	0x101ULL},
+		{"0x7fff",	16,	0x7fffULL},
+		{"0x8000",	16,	0x8000ULL},
+		{"0x8001",	16,	0x8001ULL},
+		{"0xffff",	16,	0xffffULL},
+		{"0x10000",	16,	0x10000ULL},
+		{"0x10001",	16,	0x10001ULL},
+		{"0x7fffffff",	16,	0x7fffffffULL},
+		{"0x80000000",	16,	0x80000000ULL},
+		{"0x80000001",	16,	0x80000001ULL},
+		{"0xffffffff",	16,	0xffffffffULL},
+		{"0x100000000",	16,	0x100000000ULL},
+		{"0x100000001",	16,	0x100000001ULL},
+		{"0x7fffffffffffffff",	16,	0x7fffffffffffffffULL},
+		{"0x8000000000000000",	16,	0x8000000000000000ULL},
+		{"0x8000000000000001",	16,	0x8000000000000001ULL},
+		{"0xfffffffffffffffe",	16,	0xfffffffffffffffeULL},
+		{"0xffffffffffffffff",	16,	0xffffffffffffffffULL},
+
+		{"0\n",	0,	0ULL},
+	};
+	TEST_OK(kstrtoull, unsigned long long, "%llu", test_ull_ok);
+}
+
+static void __init test_kstrtoull_fail(void)
+{
+	static DEFINE_TEST_FAIL(test_ull_fail) = {
+		{"",	0},
+		{"",	8},
+		{"",	10},
+		{"",	16},
+		{"\n",	0},
+		{"\n",	8},
+		{"\n",	10},
+		{"\n",	16},
+		{"\n0",	0},
+		{"\n0",	8},
+		{"\n0",	10},
+		{"\n0",	16},
+		{"+",	0},
+		{"+",	8},
+		{"+",	10},
+		{"+",	16},
+		{"-",	0},
+		{"-",	8},
+		{"-",	10},
+		{"-",	16},
+		{"0x",	0},
+		{"0x",	16},
+		{"0X",	0},
+		{"0X",	16},
+		{"0 ",	0},
+		{"1+",	0},
+		{"1-",	0},
+		{" 2",	0},
+		/* base autodetection */
+		{"0x0z",	0},
+		{"0z",		0},
+		{"a",		0},
+		/* digit >= base */
+		{"2",	2},
+		{"8",	8},
+		{"a",	10},
+		{"A",	10},
+		{"g",	16},
+		{"G",	16},
+		/* overflow */
+		{"10000000000000000000000000000000000000000000000000000000000000000",	2},
+		{"2000000000000000000000",	8},
+		{"18446744073709551616",	10},
+		{"10000000000000000",	16},
+		/* negative */
+		{"-0", 0},
+		{"-0", 8},
+		{"-0", 10},
+		{"-0", 16},
+		{"-1", 0},
+		{"-1", 8},
+		{"-1", 10},
+		{"-1", 16},
+		/* sign is first character if any */
+		{"-+1", 0},
+		{"-+1", 8},
+		{"-+1", 10},
+		{"-+1", 16},
+		/* nothing after \n */
+		{"0\n0", 0},
+		{"0\n0", 8},
+		{"0\n0", 10},
+		{"0\n0", 16},
+		{"0\n+", 0},
+		{"0\n+", 8},
+		{"0\n+", 10},
+		{"0\n+", 16},
+		{"0\n-", 0},
+		{"0\n-", 8},
+		{"0\n-", 10},
+		{"0\n-", 16},
+		{"0\n ", 0},
+		{"0\n ", 8},
+		{"0\n ", 10},
+		{"0\n ", 16},
+	};
+	TEST_FAIL(kstrtoull, unsigned long long, "%llu", test_ull_fail);
+}
+
+static void __init test_kstrtoll_ok(void)
+{
+	DECLARE_TEST_OK(long long, struct test_ll);
+	static DEFINE_TEST_OK(struct test_ll, test_ll_ok) = {
+		{"0",	10,	0LL},
+		{"1",	10,	1LL},
+		{"127",	10,	127LL},
+		{"128",	10,	128LL},
+		{"129",	10,	129LL},
+		{"255",	10,	255LL},
+		{"256",	10,	256LL},
+		{"257",	10,	257LL},
+		{"32767",	10,	32767LL},
+		{"32768",	10,	32768LL},
+		{"32769",	10,	32769LL},
+		{"65535",	10,	65535LL},
+		{"65536",	10,	65536LL},
+		{"65537",	10,	65537LL},
+		{"2147483647",	10,	2147483647LL},
+		{"2147483648",	10,	2147483648LL},
+		{"2147483649",	10,	2147483649LL},
+		{"4294967295",	10,	4294967295LL},
+		{"4294967296",	10,	4294967296LL},
+		{"4294967297",	10,	4294967297LL},
+		{"9223372036854775807",	10,	9223372036854775807LL},
+
+		{"-1",	10,	-1LL},
+		{"-2",	10,	-2LL},
+		{"-9223372036854775808",	10,	LLONG_MIN},
+	};
+	TEST_OK(kstrtoll, long long, "%lld", test_ll_ok);
+}
+
+static void __init test_kstrtoll_fail(void)
+{
+	static DEFINE_TEST_FAIL(test_ll_fail) = {
+		{"9223372036854775808",	10},
+		{"9223372036854775809",	10},
+		{"18446744073709551614",	10},
+		{"18446744073709551615",	10},
+		{"-9223372036854775809",	10},
+		{"-18446744073709551614",	10},
+		{"-18446744073709551615",	10},
+		/* negative zero isn't an integer in Linux */
+		{"-0",	0},
+		{"-0",	8},
+		{"-0",	10},
+		{"-0",	16},
+		/* sign is first character if any */
+		{"-+1", 0},
+		{"-+1", 8},
+		{"-+1", 10},
+		{"-+1", 16},
+	};
+	TEST_FAIL(kstrtoll, long long, "%lld", test_ll_fail);
+}
+
+static void __init test_kstrtou64_ok(void)
+{
+	DECLARE_TEST_OK(u64, struct test_u64);
+	static DEFINE_TEST_OK(struct test_u64, test_u64_ok) = {
+		{"0",	10,	0},
+		{"1",	10,	1},
+		{"126",	10,	126},
+		{"127",	10,	127},
+		{"128",	10,	128},
+		{"129",	10,	129},
+		{"254",	10,	254},
+		{"255",	10,	255},
+		{"256",	10,	256},
+		{"257",	10,	257},
+		{"32766",	10,	32766},
+		{"32767",	10,	32767},
+		{"32768",	10,	32768},
+		{"32769",	10,	32769},
+		{"65534",	10,	65534},
+		{"65535",	10,	65535},
+		{"65536",	10,	65536},
+		{"65537",	10,	65537},
+		{"2147483646",	10,	2147483646},
+		{"2147483647",	10,	2147483647},
+		{"2147483648",	10,	2147483648},
+		{"2147483649",	10,	2147483649},
+		{"4294967294",	10,	4294967294},
+		{"4294967295",	10,	4294967295},
+		{"4294967296",	10,	4294967296},
+		{"4294967297",	10,	4294967297},
+		{"9223372036854775806",	10,	9223372036854775806ULL},
+		{"9223372036854775807",	10,	9223372036854775807ULL},
+		{"9223372036854775808",	10,	9223372036854775808ULL},
+		{"9223372036854775809",	10,	9223372036854775809ULL},
+		{"18446744073709551614",	10,	18446744073709551614ULL},
+		{"18446744073709551615",	10,	18446744073709551615ULL},
+	};
+	TEST_OK(kstrtou64, u64, "%llu", test_u64_ok);
+}
+
+static void __init test_kstrtou64_fail(void)
+{
+	static DEFINE_TEST_FAIL(test_u64_fail) = {
+		{"-2",	10},
+		{"-1",	10},
+		{"18446744073709551616",	10},
+		{"18446744073709551617",	10},
+	};
+	TEST_FAIL(kstrtou64, u64, "%llu", test_u64_fail);
+}
+
+static void __init test_kstrtos64_ok(void)
+{
+	DECLARE_TEST_OK(s64, struct test_s64);
+	static DEFINE_TEST_OK(struct test_s64, test_s64_ok) = {
+		{"-128",	10,	-128},
+		{"-127",	10,	-127},
+		{"-1",	10,	-1},
+		{"0",	10,	0},
+		{"1",	10,	1},
+		{"126",	10,	126},
+		{"127",	10,	127},
+		{"128",	10,	128},
+		{"129",	10,	129},
+		{"254",	10,	254},
+		{"255",	10,	255},
+		{"256",	10,	256},
+		{"257",	10,	257},
+		{"32766",	10,	32766},
+		{"32767",	10,	32767},
+		{"32768",	10,	32768},
+		{"32769",	10,	32769},
+		{"65534",	10,	65534},
+		{"65535",	10,	65535},
+		{"65536",	10,	65536},
+		{"65537",	10,	65537},
+		{"2147483646",	10,	2147483646},
+		{"2147483647",	10,	2147483647},
+		{"2147483648",	10,	2147483648},
+		{"2147483649",	10,	2147483649},
+		{"4294967294",	10,	4294967294},
+		{"4294967295",	10,	4294967295},
+		{"4294967296",	10,	4294967296},
+		{"4294967297",	10,	4294967297},
+		{"9223372036854775806",	10,	9223372036854775806LL},
+		{"9223372036854775807",	10,	9223372036854775807LL},
+	};
+	TEST_OK(kstrtos64, s64, "%lld", test_s64_ok);
+}
+
+static void __init test_kstrtos64_fail(void)
+{
+	static DEFINE_TEST_FAIL(test_s64_fail) = {
+		{"9223372036854775808",	10},
+		{"9223372036854775809",	10},
+		{"18446744073709551614",	10},
+		{"18446744073709551615",	10},
+		{"18446744073709551616",	10},
+		{"18446744073709551617",	10},
+	};
+	TEST_FAIL(kstrtos64, s64, "%lld", test_s64_fail);
+}
+
+static void __init test_kstrtou32_ok(void)
+{
+	DECLARE_TEST_OK(u32, struct test_u32);
+	static DEFINE_TEST_OK(struct test_u32, test_u32_ok) = {
+		{"0",	10,	0},
+		{"1",	10,	1},
+		{"126",	10,	126},
+		{"127",	10,	127},
+		{"128",	10,	128},
+		{"129",	10,	129},
+		{"254",	10,	254},
+		{"255",	10,	255},
+		{"256",	10,	256},
+		{"257",	10,	257},
+		{"32766",	10,	32766},
+		{"32767",	10,	32767},
+		{"32768",	10,	32768},
+		{"32769",	10,	32769},
+		{"65534",	10,	65534},
+		{"65535",	10,	65535},
+		{"65536",	10,	65536},
+		{"65537",	10,	65537},
+		{"2147483646",	10,	2147483646},
+		{"2147483647",	10,	2147483647},
+		{"2147483648",	10,	2147483648},
+		{"2147483649",	10,	2147483649},
+		{"4294967294",	10,	4294967294},
+		{"4294967295",	10,	4294967295},
+	};
+	TEST_OK(kstrtou32, u32, "%u", test_u32_ok);
+}
+
+static void __init test_kstrtou32_fail(void)
+{
+	static DEFINE_TEST_FAIL(test_u32_fail) = {
+		{"-2",	10},
+		{"-1",	10},
+		{"4294967296",	10},
+		{"4294967297",	10},
+		{"9223372036854775806",	10},
+		{"9223372036854775807",	10},
+		{"9223372036854775808",	10},
+		{"9223372036854775809",	10},
+		{"18446744073709551614",	10},
+		{"18446744073709551615",	10},
+		{"18446744073709551616",	10},
+		{"18446744073709551617",	10},
+	};
+	TEST_FAIL(kstrtou32, u32, "%u", test_u32_fail);
+}
+
+static void __init test_kstrtos32_ok(void)
+{
+	DECLARE_TEST_OK(s32, struct test_s32);
+	static DEFINE_TEST_OK(struct test_s32, test_s32_ok) = {
+		{"-128",	10,	-128},
+		{"-127",	10,	-127},
+		{"-1",	10,	-1},
+		{"0",	10,	0},
+		{"1",	10,	1},
+		{"126",	10,	126},
+		{"127",	10,	127},
+		{"128",	10,	128},
+		{"129",	10,	129},
+		{"254",	10,	254},
+		{"255",	10,	255},
+		{"256",	10,	256},
+		{"257",	10,	257},
+		{"32766",	10,	32766},
+		{"32767",	10,	32767},
+		{"32768",	10,	32768},
+		{"32769",	10,	32769},
+		{"65534",	10,	65534},
+		{"65535",	10,	65535},
+		{"65536",	10,	65536},
+		{"65537",	10,	65537},
+		{"2147483646",	10,	2147483646},
+		{"2147483647",	10,	2147483647},
+	};
+	TEST_OK(kstrtos32, s32, "%d", test_s32_ok);
+}
+
+static void __init test_kstrtos32_fail(void)
+{
+	static DEFINE_TEST_FAIL(test_s32_fail) = {
+		{"2147483648",	10},
+		{"2147483649",	10},
+		{"4294967294",	10},
+		{"4294967295",	10},
+		{"4294967296",	10},
+		{"4294967297",	10},
+		{"9223372036854775806",	10},
+		{"9223372036854775807",	10},
+		{"9223372036854775808",	10},
+		{"9223372036854775809",	10},
+		{"18446744073709551614",	10},
+		{"18446744073709551615",	10},
+		{"18446744073709551616",	10},
+		{"18446744073709551617",	10},
+	};
+	TEST_FAIL(kstrtos32, s32, "%d", test_s32_fail);
+}
+
+static void __init test_kstrtou16_ok(void)
+{
+	DECLARE_TEST_OK(u16, struct test_u16);
+	static DEFINE_TEST_OK(struct test_u16, test_u16_ok) = {
+		{"0",	10,	0},
+		{"1",	10,	1},
+		{"126",	10,	126},
+		{"127",	10,	127},
+		{"128",	10,	128},
+		{"129",	10,	129},
+		{"254",	10,	254},
+		{"255",	10,	255},
+		{"256",	10,	256},
+		{"257",	10,	257},
+		{"32766",	10,	32766},
+		{"32767",	10,	32767},
+		{"32768",	10,	32768},
+		{"32769",	10,	32769},
+		{"65534",	10,	65534},
+		{"65535",	10,	65535},
+	};
+	TEST_OK(kstrtou16, u16, "%hu", test_u16_ok);
+}
+
+static void __init test_kstrtou16_fail(void)
+{
+	static DEFINE_TEST_FAIL(test_u16_fail) = {
+		{"-2",	10},
+		{"-1",	10},
+		{"65536",	10},
+		{"65537",	10},
+		{"2147483646",	10},
+		{"2147483647",	10},
+		{"2147483648",	10},
+		{"2147483649",	10},
+		{"4294967294",	10},
+		{"4294967295",	10},
+		{"4294967296",	10},
+		{"4294967297",	10},
+		{"9223372036854775806",	10},
+		{"9223372036854775807",	10},
+		{"9223372036854775808",	10},
+		{"9223372036854775809",	10},
+		{"18446744073709551614",	10},
+		{"18446744073709551615",	10},
+		{"18446744073709551616",	10},
+		{"18446744073709551617",	10},
+	};
+	TEST_FAIL(kstrtou16, u16, "%hu", test_u16_fail);
+}
+
+static void __init test_kstrtos16_ok(void)
+{
+	DECLARE_TEST_OK(s16, struct test_s16);
+	static DEFINE_TEST_OK(struct test_s16, test_s16_ok) = {
+		{"-130",	10,	-130},
+		{"-129",	10,	-129},
+		{"-128",	10,	-128},
+		{"-127",	10,	-127},
+		{"-1",	10,	-1},
+		{"0",	10,	0},
+		{"1",	10,	1},
+		{"126",	10,	126},
+		{"127",	10,	127},
+		{"128",	10,	128},
+		{"129",	10,	129},
+		{"254",	10,	254},
+		{"255",	10,	255},
+		{"256",	10,	256},
+		{"257",	10,	257},
+		{"32766",	10,	32766},
+		{"32767",	10,	32767},
+	};
+	TEST_OK(kstrtos16, s16, "%hd", test_s16_ok);
+}
+
+static void __init test_kstrtos16_fail(void)
+{
+	static DEFINE_TEST_FAIL(test_s16_fail) = {
+		{"32768",	10},
+		{"32769",	10},
+		{"65534",	10},
+		{"65535",	10},
+		{"65536",	10},
+		{"65537",	10},
+		{"2147483646",	10},
+		{"2147483647",	10},
+		{"2147483648",	10},
+		{"2147483649",	10},
+		{"4294967294",	10},
+		{"4294967295",	10},
+		{"4294967296",	10},
+		{"4294967297",	10},
+		{"9223372036854775806",	10},
+		{"9223372036854775807",	10},
+		{"9223372036854775808",	10},
+		{"9223372036854775809",	10},
+		{"18446744073709551614",	10},
+		{"18446744073709551615",	10},
+		{"18446744073709551616",	10},
+		{"18446744073709551617",	10},
+	};
+	TEST_FAIL(kstrtos16, s16, "%hd", test_s16_fail);
+}
+
+static void __init test_kstrtou8_ok(void)
+{
+	DECLARE_TEST_OK(u8, struct test_u8);
+	static DEFINE_TEST_OK(struct test_u8, test_u8_ok) = {
+		{"0",	10,	0},
+		{"1",	10,	1},
+		{"126",	10,	126},
+		{"127",	10,	127},
+		{"128",	10,	128},
+		{"129",	10,	129},
+		{"254",	10,	254},
+		{"255",	10,	255},
+	};
+	TEST_OK(kstrtou8, u8, "%hhu", test_u8_ok);
+}
+
+static void __init test_kstrtou8_fail(void)
+{
+	static DEFINE_TEST_FAIL(test_u8_fail) = {
+		{"-2",	10},
+		{"-1",	10},
+		{"256",	10},
+		{"257",	10},
+		{"32766",	10},
+		{"32767",	10},
+		{"32768",	10},
+		{"32769",	10},
+		{"65534",	10},
+		{"65535",	10},
+		{"65536",	10},
+		{"65537",	10},
+		{"2147483646",	10},
+		{"2147483647",	10},
+		{"2147483648",	10},
+		{"2147483649",	10},
+		{"4294967294",	10},
+		{"4294967295",	10},
+		{"4294967296",	10},
+		{"4294967297",	10},
+		{"9223372036854775806",	10},
+		{"9223372036854775807",	10},
+		{"9223372036854775808",	10},
+		{"9223372036854775809",	10},
+		{"18446744073709551614",	10},
+		{"18446744073709551615",	10},
+		{"18446744073709551616",	10},
+		{"18446744073709551617",	10},
+	};
+	TEST_FAIL(kstrtou8, u8, "%hhu", test_u8_fail);
+}
+
+static void __init test_kstrtos8_ok(void)
+{
+	DECLARE_TEST_OK(s8, struct test_s8);
+	static DEFINE_TEST_OK(struct test_s8, test_s8_ok) = {
+		{"-128",	10,	-128},
+		{"-127",	10,	-127},
+		{"-1",	10,	-1},
+		{"0",	10,	0},
+		{"1",	10,	1},
+		{"126",	10,	126},
+		{"127",	10,	127},
+	};
+	TEST_OK(kstrtos8, s8, "%hhd", test_s8_ok);
+}
+
+static void __init test_kstrtos8_fail(void)
+{
+	static DEFINE_TEST_FAIL(test_s8_fail) = {
+		{"-130",	10},
+		{"-129",	10},
+		{"128",	10},
+		{"129",	10},
+		{"254",	10},
+		{"255",	10},
+		{"256",	10},
+		{"257",	10},
+		{"32766",	10},
+		{"32767",	10},
+		{"32768",	10},
+		{"32769",	10},
+		{"65534",	10},
+		{"65535",	10},
+		{"65536",	10},
+		{"65537",	10},
+		{"2147483646",	10},
+		{"2147483647",	10},
+		{"2147483648",	10},
+		{"2147483649",	10},
+		{"4294967294",	10},
+		{"4294967295",	10},
+		{"4294967296",	10},
+		{"4294967297",	10},
+		{"9223372036854775806",	10},
+		{"9223372036854775807",	10},
+		{"9223372036854775808",	10},
+		{"9223372036854775809",	10},
+		{"18446744073709551614",	10},
+		{"18446744073709551615",	10},
+		{"18446744073709551616",	10},
+		{"18446744073709551617",	10},
+	};
+	TEST_FAIL(kstrtos8, s8, "%hhd", test_s8_fail);
+}
+
+static int __init test_kstrtox_init(void)
+{
+	test_kstrtoull_ok();
+	test_kstrtoull_fail();
+	test_kstrtoll_ok();
+	test_kstrtoll_fail();
+
+	test_kstrtou64_ok();
+	test_kstrtou64_fail();
+	test_kstrtos64_ok();
+	test_kstrtos64_fail();
+
+	test_kstrtou32_ok();
+	test_kstrtou32_fail();
+	test_kstrtos32_ok();
+	test_kstrtos32_fail();
+
+	test_kstrtou16_ok();
+	test_kstrtou16_fail();
+	test_kstrtos16_ok();
+	test_kstrtos16_fail();
+
+	test_kstrtou8_ok();
+	test_kstrtou8_fail();
+	test_kstrtos8_ok();
+	test_kstrtos8_fail();
+	return -EINVAL;
+}
+module_init(test_kstrtox_init);
+MODULE_LICENSE("Dual BSD/GPL");
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index ac444ff01658..02bcdd5feac4 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -120,147 +120,6 @@ long long simple_strtoll(const char *cp, char **endp, unsigned int base)
 }
 EXPORT_SYMBOL(simple_strtoll);
 
-/**
- * strict_strtoul - convert a string to an unsigned long strictly
- * @cp: The string to be converted
- * @base: The number base to use
- * @res: The converted result value
- *
- * strict_strtoul converts a string to an unsigned long only if the
- * string is really an unsigned long string, any string containing
- * any invalid char at the tail will be rejected and -EINVAL is returned,
- * only a newline char at the tail is acceptible because people generally
- * change a module parameter in the following way:
- *
- * 	echo 1024 > /sys/module/e1000/parameters/copybreak
- *
- * echo will append a newline to the tail.
- *
- * It returns 0 if conversion is successful and *res is set to the converted
- * value, otherwise it returns -EINVAL and *res is set to 0.
- *
- * simple_strtoul just ignores the successive invalid characters and
- * return the converted value of prefix part of the string.
- */
-int strict_strtoul(const char *cp, unsigned int base, unsigned long *res)
-{
-	char *tail;
-	unsigned long val;
-
-	*res = 0;
-	if (!*cp)
-		return -EINVAL;
-
-	val = simple_strtoul(cp, &tail, base);
-	if (tail == cp)
-		return -EINVAL;
-
-	if ((tail[0] == '\0') || (tail[0] == '\n' && tail[1] == '\0')) {
-		*res = val;
-		return 0;
-	}
-
-	return -EINVAL;
-}
-EXPORT_SYMBOL(strict_strtoul);
-
-/**
- * strict_strtol - convert a string to a long strictly
- * @cp: The string to be converted
- * @base: The number base to use
- * @res: The converted result value
- *
- * strict_strtol is similiar to strict_strtoul, but it allows the first
- * character of a string is '-'.
- *
- * It returns 0 if conversion is successful and *res is set to the converted
- * value, otherwise it returns -EINVAL and *res is set to 0.
- */
-int strict_strtol(const char *cp, unsigned int base, long *res)
-{
-	int ret;
-	if (*cp == '-') {
-		ret = strict_strtoul(cp + 1, base, (unsigned long *)res);
-		if (!ret)
-			*res = -(*res);
-	} else {
-		ret = strict_strtoul(cp, base, (unsigned long *)res);
-	}
-
-	return ret;
-}
-EXPORT_SYMBOL(strict_strtol);
-
-/**
- * strict_strtoull - convert a string to an unsigned long long strictly
- * @cp: The string to be converted
- * @base: The number base to use
- * @res: The converted result value
- *
- * strict_strtoull converts a string to an unsigned long long only if the
- * string is really an unsigned long long string, any string containing
- * any invalid char at the tail will be rejected and -EINVAL is returned,
- * only a newline char at the tail is acceptible because people generally
- * change a module parameter in the following way:
- *
- * 	echo 1024 > /sys/module/e1000/parameters/copybreak
- *
- * echo will append a newline to the tail of the string.
- *
- * It returns 0 if conversion is successful and *res is set to the converted
- * value, otherwise it returns -EINVAL and *res is set to 0.
- *
- * simple_strtoull just ignores the successive invalid characters and
- * return the converted value of prefix part of the string.
- */
-int strict_strtoull(const char *cp, unsigned int base, unsigned long long *res)
-{
-	char *tail;
-	unsigned long long val;
-
-	*res = 0;
-	if (!*cp)
-		return -EINVAL;
-
-	val = simple_strtoull(cp, &tail, base);
-	if (tail == cp)
-		return -EINVAL;
-	if ((tail[0] == '\0') || (tail[0] == '\n' && tail[1] == '\0')) {
-		*res = val;
-		return 0;
-	}
-
-	return -EINVAL;
-}
-EXPORT_SYMBOL(strict_strtoull);
-
-/**
- * strict_strtoll - convert a string to a long long strictly
- * @cp: The string to be converted
- * @base: The number base to use
- * @res: The converted result value
- *
- * strict_strtoll is similiar to strict_strtoull, but it allows the first
- * character of a string is '-'.
- *
- * It returns 0 if conversion is successful and *res is set to the converted
- * value, otherwise it returns -EINVAL and *res is set to 0.
- */
-int strict_strtoll(const char *cp, unsigned int base, long long *res)
-{
-	int ret;
-	if (*cp == '-') {
-		ret = strict_strtoull(cp + 1, base, (unsigned long long *)res);
-		if (!ret)
-			*res = -(*res);
-	} else {
-		ret = strict_strtoull(cp, base, (unsigned long long *)res);
-	}
-
-	return ret;
-}
-EXPORT_SYMBOL(strict_strtoll);
-
 static noinline_for_stack
 int skip_atoi(const char **s)
 {