[patch 6/9] x86/uaccess: Add missing __force to casts in __access_ok() and valid_user_address()

Thomas Gleixner
2024-03-04T10:12:27Z

sparse complains about losing the __user address space due to the cast to
long:

uaccess_64.h:88:24: sparse: warning: cast removes address space '__user' of expression

Annotate it with __force to tell sparse that this is intentional.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/include/asm/uaccess_64.h | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

--- a/arch/x86/include/asm/uaccess_64.h
+++ b/arch/x86/include/asm/uaccess_64.h
@@ -54,7 +54,7 @@ static inline unsigned long __untagged_a
* half and a user half. When cast to a signed type, user pointers
* are positive and kernel pointers are negative.
*/
-#define valid_user_address(x) ((long)(x) >= 0)
+#define valid_user_address(x) ((__force long)(x) >= 0)

/*
* User pointers can have tag bits on x86-64. This scheme tolerates
@@ -87,8 +87,9 @@ static inline bool __access_ok(const voi
if (__builtin_constant_p(size <= PAGE_SIZE) && size <= PAGE_SIZE) {
return valid_user_address(ptr);
} else {
- unsigned long sum = size + (unsigned long)ptr;
- return valid_user_address(sum) && sum >= (unsigned long)ptr;
+ unsigned long sum = size + (__force unsigned long)ptr;
+
+ return valid_user_address(sum) && sum >= (__force unsigned long)ptr;
}
}
#define __access_ok __access_ok