1 files changed, 26 insertions, 0 deletions

diff --git a/lib/kstrtox.c b/lib/kstrtox.c
index a235f3cc471c..2dbae88090ac 100644
--- a/lib/kstrtox.c
+++ b/lib/kstrtox.c
@@ -17,6 +17,7 @@
 #include <linux/math64.h>
 #include <linux/module.h>
 #include <linux/types.h>
+#include <asm/uaccess.h>
 
 static inline char _tolower(const char c)
 {
@@ -222,3 +223,28 @@ int kstrtos8(const char *s, unsigned int base, s8 *res)
         return 0;
 }
 EXPORT_SYMBOL(kstrtos8);
+
+#define kstrto_from_user(f, g, type)                                    \
+int f(const char __user *s, size_t count, unsigned int base, type *res) \
+{                                                                       \
+        /* sign, base 2 representation, newline, terminator */          \
+        char buf[1 + sizeof(type) * 8 + 1 + 1];                         \
+                                                                        \
+        count = min(count, sizeof(buf) - 1);                            \
+        if (copy_from_user(buf, s, count))                              \
+                return -EFAULT;                                         \
+        buf[count] = '\0';                                              \
+        return g(buf, base, res);                                       \
+}                                                                       \
+EXPORT_SYMBOL(f)
+
+kstrto_from_user(kstrtoull_from_user,   kstrtoull,      unsigned long long);
+kstrto_from_user(kstrtoll_from_user,    kstrtoll,       long long);
+kstrto_from_user(kstrtoul_from_user,    kstrtoul,       unsigned long);
+kstrto_from_user(kstrtol_from_user,     kstrtol,        long);
+kstrto_from_user(kstrtouint_from_user,  kstrtouint,     unsigned int);
+kstrto_from_user(kstrtoint_from_user,   kstrtoint,      int);
+kstrto_from_user(kstrtou16_from_user,   kstrtou16,      u16);
+kstrto_from_user(kstrtos16_from_user,   kstrtos16,      s16);
+kstrto_from_user(kstrtou8_from_user,    kstrtou8,       u8);
+kstrto_from_user(kstrtos8_from_user,    kstrtos8,       s8);