asm-generic: zero in __get_user(), not __get_user_fn()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 6 insertions, 12 deletions

diff --git a/include/asm-generic/uaccess.h b/include/asm-generic/uaccess.h
index b048246a606b..bd7a05e9582b 100644
--- a/include/asm-generic/uaccess.h
+++ b/include/asm-generic/uaccess.h
@@ -86,8 +86,7 @@ static inline int __access_ok(unsigned long addr, unsigned long size)
 
 static inline int __put_user_fn(size_t size, void __user *ptr, void *x)
 {
-        size = __copy_to_user(ptr, x, size);
-        return size ? -EFAULT : size;
+        return unlikely(__copy_to_user(ptr, x, size)) ? -EFAULT : 0;
 }
 
 #define __put_user_fn(sz, u, k) __put_user_fn(sz, u, k)
@@ -102,28 +101,28 @@ extern int __put_user_bad(void) __attribute__((noreturn));
         __chk_user_ptr(ptr);                                    \
         switch (sizeof(*(ptr))) {                               \
         case 1: {                                               \
-                unsigned char __x;                              \
+                unsigned char __x = 0;                          \
                 __gu_err = __get_user_fn(sizeof (*(ptr)),       \
                                          ptr, &__x);            \
                 (x) = *(__force __typeof__(*(ptr)) *) &__x;     \
                 break;                                          \
         };                                                      \
         case 2: {                                               \
-                unsigned short __x;                             \
+                unsigned short __x = 0;                         \
                 __gu_err = __get_user_fn(sizeof (*(ptr)),       \
                                          ptr, &__x);            \
                 (x) = *(__force __typeof__(*(ptr)) *) &__x;     \
                 break;                                          \
         };                                                      \
         case 4: {                                               \
-                unsigned int __x;                               \
+                unsigned int __x = 0;                           \
                 __gu_err = __get_user_fn(sizeof (*(ptr)),       \
                                          ptr, &__x);            \
                 (x) = *(__force __typeof__(*(ptr)) *) &__x;     \
                 break;                                          \
         };                                                      \
         case 8: {                                               \
-                unsigned long long __x;                         \
+                unsigned long long __x = 0;                     \
                 __gu_err = __get_user_fn(sizeof (*(ptr)),       \
                                          ptr, &__x);            \
                 (x) = *(__force __typeof__(*(ptr)) *) &__x;     \
@@ -148,12 +147,7 @@ extern int __put_user_bad(void) __attribute__((noreturn));
 #ifndef __get_user_fn
 static inline int __get_user_fn(size_t size, const void __user *ptr, void *x)
 {
-        size_t n = __copy_from_user(x, ptr, size);
-        if (unlikely(n)) {
-                memset(x + (size - n), 0, n);
-                return -EFAULT;
-        }
-        return 0;
+        return unlikely(__copy_from_user(x, ptr, size)) ? -EFAULT : 0;
 }
 
 #define __get_user_fn(sz, u, k) __get_user_fn(sz, u, k)