ia64: copy_from_user() should zero the destination on access_ok() failure

[cascardo/linux.git] / arch / ia64 / include / asm / uaccess.h

diff --git a/arch/ia64/include/asm/uaccess.h b/arch/ia64/include/asm/uaccess.h
index 2189d5d..6c2d2c8 100644 (file)
--- a/arch/ia64/include/asm/uaccess.h
+++ b/arch/ia64/include/asm/uaccess.h
@@ -241,12 +241,18 @@ extern unsigned long __must_check __copy_user (void __user *to, const void __use
 static inline unsigned long
 __copy_to_user (void __user *to, const void *from, unsigned long count)
 {
+       if (!__builtin_constant_p(count))
+               check_object_size(from, count, true);
+
        return __copy_user(to, (__force void __user *) from, count);
 }
 
 static inline unsigned long
 __copy_from_user (void *to, const void __user *from, unsigned long count)
 {
+       if (!__builtin_constant_p(count))
+               check_object_size(to, count, false);
+
        return __copy_user((__force void __user *) to, from, count);
 }
 
@@ -258,22 +264,25 @@ __copy_from_user (void *to, const void __user *from, unsigned long count)
        const void *__cu_from = (from);                                                 \
        long __cu_len = (n);                                                            \
                                                                                        \
-       if (__access_ok(__cu_to, __cu_len, get_fs()))                                   \
-               __cu_len = __copy_user(__cu_to, (__force void __user *) __cu_from, __cu_len);   \
+       if (__access_ok(__cu_to, __cu_len, get_fs())) {                                 \
+               if (!__builtin_constant_p(n))                                           \
+                       check_object_size(__cu_from, __cu_len, true);                   \
+               __cu_len = __copy_user(__cu_to, (__force void __user *)  __cu_from, __cu_len);  \
+       }                                                                               \
        __cu_len;                                                                       \
 })
 
-#define copy_from_user(to, from, n)                                                    \
-({                                                                                     \
-       void *__cu_to = (to);                                                           \
-       const void __user *__cu_from = (from);                                          \
-       long __cu_len = (n);                                                            \
-                                                                                       \
-       __chk_user_ptr(__cu_from);                                                      \
-       if (__access_ok(__cu_from, __cu_len, get_fs()))                                 \
-               __cu_len = __copy_user((__force void __user *) __cu_to, __cu_from, __cu_len);   \
-       __cu_len;                                                                       \
-})
+static inline unsigned long
+copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+       if (!__builtin_constant_p(n))
+               check_object_size(to, n, false);
+       if (likely(__access_ok(from, n, get_fs())))
+               n = __copy_user((__force void __user *) to, from, n);
+       else
+               memset(to, 0, n);
+       return n;
+}
 
 #define __copy_in_user(to, from, size) __copy_user((to), (from), (size))