lib: move strtobool() to kstrtobool()

commit ef951599074ba4fad2d0efa0a977129b41e6d203 upstream.

Create the kstrtobool_from_user() helper and move strtobool() logic into
the new kstrtobool() (matching all the other kstrto* functions).
Provides an inline wrapper for existing strtobool() callers.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Joe Perches <joe@perches.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Amitkumar Karwar <akarwar@marvell.com>
Cc: Nishant Sarmukadam <nishants@marvell.com>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: Steve French <sfrench@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index e571e592e53a10d86b0d969f01933a6edee26506..50220cab738c1d816f7f4117c2ae19baeb2561da 100644 (file)
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -356,6 +356,7 @@ int __must_check kstrtou16(const char *s, unsigned int base, u16 *res);
 int __must_check kstrtos16(const char *s, unsigned int base, s16 *res);
 int __must_check kstrtou8(const char *s, unsigned int base, u8 *res);
 int __must_check kstrtos8(const char *s, unsigned int base, s8 *res);
+int __must_check kstrtobool(const char *s, bool *res);
 
 int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res);
 int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res);
@@ -367,6 +368,7 @@ int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigne
 int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res);
 int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res);
 int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res);
+int __must_check kstrtobool_from_user(const char __user *s, size_t count, bool *res);
 
 static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res)
 {

diff --git a/include/linux/string.h b/include/linux/string.h
index 9ef7795e65e40c5dfbee53726909fbcb2ce341b0..aa30789b0f65eea407dfc56c68f9817c756f281d 100644 (file)
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -127,7 +127,11 @@ extern char **argv_split(gfp_t gfp, const char *str, int *argcp);
 extern void argv_free(char **argv);
 
 extern bool sysfs_streq(const char *s1, const char *s2);
-extern int strtobool(const char *s, bool *res);
+extern int kstrtobool(const char *s, bool *res);
+static inline int strtobool(const char *s, bool *res)
+{
+       return kstrtobool(s, res);
+}
 
 #ifdef CONFIG_BINARY_PRINTF
 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args);

diff --git a/lib/kstrtox.c b/lib/kstrtox.c
index 94be244e844103d0fb6ed20c7bee905ca908fa12..e8ba4a013e82f558565da40fba86473ce5e1a091 100644 (file)
--- a/lib/kstrtox.c
+++ b/lib/kstrtox.c
@@ -321,6 +321,56 @@ int kstrtos8(const char *s, unsigned int base, s8 *res)
 }
 EXPORT_SYMBOL(kstrtos8);
 
+/**
+ * kstrtobool - convert common user inputs into boolean values
+ * @s: input string
+ * @res: result
+ *
+ * This routine returns 0 iff the first character is one of 'Yy1Nn0'.
+ * Otherwise it will return -EINVAL.  Value pointed to by res is
+ * updated upon finding a match.
+ */
+int kstrtobool(const char *s, bool *res)
+{
+       if (!s)
+               return -EINVAL;
+
+       switch (s[0]) {
+       case 'y':
+       case 'Y':
+       case '1':
+               *res = true;
+               return 0;
+       case 'n':
+       case 'N':
+       case '0':
+               *res = false;
+               return 0;
+       default:
+               break;
+       }
+
+       return -EINVAL;
+}
+EXPORT_SYMBOL(kstrtobool);
+
+/*
+ * Since "base" would be a nonsense argument, this open-codes the
+ * _from_user helper instead of using the helper macro below.
+ */
+int kstrtobool_from_user(const char __user *s, size_t count, bool *res)
+{
+       /* Longest string needed to differentiate, newline, terminator */
+       char buf[4];
+
+       count = min(count, sizeof(buf) - 1);
+       if (copy_from_user(buf, s, count))
+               return -EFAULT;
+       buf[count] = '\0';
+       return kstrtobool(buf, res);
+}
+EXPORT_SYMBOL(kstrtobool_from_user);
+
 #define kstrto_from_user(f, g, type)                                   \
 int f(const char __user *s, size_t count, unsigned int base, type *res)        \
 {                                                                      \

diff --git a/lib/string.c b/lib/string.c
index 0323c0d5629af31e674bcfa24624e0917e2bb80d..1a90db9bc6e1b474099ff9f967efd74101451596 100644 (file)
--- a/lib/string.c
+++ b/lib/string.c
@@ -630,35 +630,6 @@ bool sysfs_streq(const char *s1, const char *s2)
 }
 EXPORT_SYMBOL(sysfs_streq);
 
-/**
- * strtobool - convert common user inputs into boolean values
- * @s: input string
- * @res: result
- *
- * This routine returns 0 iff the first character is one of 'Yy1Nn0'.
- * Otherwise it will return -EINVAL.  Value pointed to by res is
- * updated upon finding a match.
- */
-int strtobool(const char *s, bool *res)
-{
-       switch (s[0]) {
-       case 'y':
-       case 'Y':
-       case '1':
-               *res = true;
-               break;
-       case 'n':
-       case 'N':
-       case '0':
-               *res = false;
-               break;
-       default:
-               return -EINVAL;
-       }
-       return 0;
-}
-EXPORT_SYMBOL(strtobool);
-
 #ifndef __HAVE_ARCH_MEMSET
 /**
  * memset - Fill a region of memory with the given value