On 3/29/2019 10:00 PM, Jann Horn wrote:
The first two arguments of __user_atomic_cmpxchg_inatomic() are:
- `uval` is a kernel pointer into which the old value should be stored
- `ptr` is the user pointer on which the cmpxchg should operate
This means that casting `uval` to `__typeof__(ptr)` is wrong. Since `uval`
is only used once inside the macro, just get rid of __uval and use `(uval)`
directly.
Signed-off-by: Jann Horn <ja...@google.com>
Looks good to me.
Reviewed-by: Mukesh Ojha <mo...@codeaurora.org>
Cheers,
-Mukesh
---
arch/x86/include/asm/uaccess.h | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index 1954dd5552a2..a21f2a2f17bf 100644
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -585,7 +585,6 @@ extern void __cmpxchg_wrong_size(void)
#define __user_atomic_cmpxchg_inatomic(uval, ptr, old, new, size) \
({ \
int __ret = 0; \
- __typeof__(ptr) __uval = (uval); \
__typeof__(*(ptr)) __old = (old); \
__typeof__(*(ptr)) __new = (new); \
__uaccess_begin_nospec(); \
@@ -661,7 +660,7 @@ extern void __cmpxchg_wrong_size(void)
__cmpxchg_wrong_size(); \
} \
__uaccess_end(); \
- *__uval = __old; \
+ *(uval) = __old; \
__ret; \
})
