score: fix copy_from_user() and friends

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

1 files changed, 20 insertions, 21 deletions

diff --git a/arch/score/include/asm/uaccess.h b/arch/score/include/asm/uaccess.h
index c5d43111a5cc..01aec8ccde83 100644
--- a/arch/score/include/asm/uaccess.h
+++ b/arch/score/include/asm/uaccess.h
@@ -301,35 +301,34 @@ extern int __copy_tofrom_user(void *to, const void *from, unsigned long len);
 static inline unsigned long
 copy_from_user(void *to, const void *from, unsigned long len)
 {
-        unsigned long over;
+        unsigned long res = len;
 
-        if (access_ok(VERIFY_READ, from, len))
-                return __copy_tofrom_user(to, from, len);
+        if (likely(access_ok(VERIFY_READ, from, len)))
+                res = __copy_tofrom_user(to, from, len);
 
-        if ((unsigned long)from < TASK_SIZE) {
-                over = (unsigned long)from + len - TASK_SIZE;
-                return __copy_tofrom_user(to, from, len - over) + over;
-        }
-        return len;
+        if (unlikely(res))
+                memset(to + (len - res), 0, res);
+
+        return res;
 }
 
 static inline unsigned long
 copy_to_user(void *to, const void *from, unsigned long len)
 {
-        unsigned long over;
-
-        if (access_ok(VERIFY_WRITE, to, len))
-                return __copy_tofrom_user(to, from, len);
+        if (likely(access_ok(VERIFY_WRITE, to, len)))
+                len = __copy_tofrom_user(to, from, len);
 
-        if ((unsigned long)to < TASK_SIZE) {
-                over = (unsigned long)to + len - TASK_SIZE;
-                return __copy_tofrom_user(to, from, len - over) + over;
-        }
         return len;
 }
 
-#define __copy_from_user(to, from, len) \
-                __copy_tofrom_user((to), (from), (len))
+static inline unsigned long
+__copy_from_user(void *to, const void *from, unsigned long len)
+{
+        unsigned long left = __copy_tofrom_user(to, from, len);
+        if (unlikely(left))
+                memset(to + (len - left), 0, left);
+        return left;
+}
 
 #define __copy_to_user(to, from, len)           \
                 __copy_tofrom_user((to), (from), (len))
@@ -343,17 +342,17 @@ __copy_to_user_inatomic(void *to, const void *from, unsigned long len)
 static inline unsigned long
 __copy_from_user_inatomic(void *to, const void *from, unsigned long len)
 {
-        return __copy_from_user(to, from, len);
+        return __copy_tofrom_user(to, from, len);
 }
 
-#define __copy_in_user(to, from, len)   __copy_from_user(to, from, len)
+#define __copy_in_user(to, from, len)   __copy_tofrom_user(to, from, len)
 
 static inline unsigned long
 copy_in_user(void *to, const void *from, unsigned long len)
 {
         if (access_ok(VERIFY_READ, from, len) &&
                       access_ok(VERFITY_WRITE, to, len))
-                return copy_from_user(to, from, len);
+                return __copy_tofrom_user(to, from, len);
 }
 
 /*