tile: enable sparse checks for get/put_user

Add an extra intermediate variable to __get_user and __put_user
to give sparse an opportunity to detect mismatches.

Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>

diff --git a/arch/tile/include/asm/uaccess.h b/arch/tile/include/asm/uaccess.h
index b81b24a..f41cb53 100644 (file)
--- a/arch/tile/include/asm/uaccess.h
+++ b/arch/tile/include/asm/uaccess.h
@@ -210,14 +210,16 @@ extern int __get_user_bad(void)
 #define __get_user(x, ptr)                                             \
        ({                                                              \
                int __ret;                                              \
 #define __get_user(x, ptr)                                             \
        ({                                                              \
                int __ret;                                              \

+               typeof(x) _x;                                           \

                __chk_user_ptr(ptr);                                    \
                switch (sizeof(*(ptr))) {                               \
                __chk_user_ptr(ptr);                                    \
                switch (sizeof(*(ptr))) {                               \

-               case 1: __get_user_1(x, ptr, __ret); break;             \
-               case 2: __get_user_2(x, ptr, __ret); break;             \
-               case 4: __get_user_4(x, ptr, __ret); break;             \
-               case 8: __get_user_8(x, ptr, __ret); break;             \
+               case 1: __get_user_1(_x, ptr, __ret); break;            \
+               case 2: __get_user_2(_x, ptr, __ret); break;            \
+               case 4: __get_user_4(_x, ptr, __ret); break;            \
+               case 8: __get_user_8(_x, ptr, __ret); break;            \

                default: __ret = __get_user_bad(); break;               \
                }                                                       \
                default: __ret = __get_user_bad(); break;               \
                }                                                       \

+               (x) = (typeof(*(ptr))) _x;                              \

                __ret;                                                  \
        })
 
                __ret;                                                  \
        })
 


@@ -289,12 +291,13 @@ extern int __put_user_bad(void)
 #define __put_user(x, ptr)                                             \
 ({                                                                     \
        int __ret;                                                      \
 #define __put_user(x, ptr)                                             \
 ({                                                                     \
        int __ret;                                                      \

+       typeof(*(ptr)) _x = (x);                                        \

        __chk_user_ptr(ptr);                                            \
        switch (sizeof(*(ptr))) {                                       \
        __chk_user_ptr(ptr);                                            \
        switch (sizeof(*(ptr))) {                                       \

-       case 1: __put_user_1(x, ptr, __ret); break;                     \
-       case 2: __put_user_2(x, ptr, __ret); break;                     \
-       case 4: __put_user_4(x, ptr, __ret); break;                     \
-       case 8: __put_user_8(x, ptr, __ret); break;                     \
+       case 1: __put_user_1(_x, ptr, __ret); break;                    \
+       case 2: __put_user_2(_x, ptr, __ret); break;                    \
+       case 4: __put_user_4(_x, ptr, __ret); break;                    \
+       case 8: __put_user_8(_x, ptr, __ret); break;                    \

        default: __ret = __put_user_bad(); break;                       \
        }                                                               \
        __ret;                                                          \
        default: __ret = __put_user_bad(); break;                       \
        }                                                               \
        __ret;                                                          \