The following commit has been merged into the x86/mm branch of tip:
Commit-ID: ce66a02538f39f071443bac9bc6ff8f3a780ab92
Gitweb: https://git.kernel.org/tip/ce66a02538f39f071443bac9bc6ff8f3a780ab92
Author: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
AuthorDate: Wed, 16 Nov 2022 03:43:53 +03:00
Committer: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
CommitterDate: Mon, 28 Nov 2022 15:12:25 -08:00
x86/mm: Fix sparse warnings in untagged_ptr()
Linear Address Masking patchset triggered a lot of sparse warnings.
The root cause is that casting pointer to '__typeof__(*(ptr)) *' will
strip all sparse tags. The type has to be defined based on the pointer
type, not based on what the pointer points to.
Fix cast in untagged_ptr() and avoid __typeof__() usage in
get/put_user().
Fixes: 5744534bdae4 ("x86/uaccess: Provide untagged_addr() and remove tags before address check")
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/all/20221116004353.15052-3-kirill.shutemov%40linux.intel.com
---
arch/x86/include/asm/uaccess.h | 10 +++-------
1 file changed, 3 insertions(+), 7 deletions(-)
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index 1d2c792..bd92e1e 100644
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -43,7 +43,7 @@ DECLARE_STATIC_KEY_FALSE(tagged_addr_key);
#define untagged_ptr(mm, ptr) ({ \
u64 __ptrval = (__force u64)(ptr); \
__ptrval = untagged_addr(mm, __ptrval); \
- (__force __typeof__(*(ptr)) *)__ptrval; \
+ (__force __typeof__(ptr))__ptrval; \
})
#else
#define untagged_addr(mm, addr) (addr)
@@ -158,10 +158,8 @@ extern int __get_user_bad(void);
*/
#define get_user(x,ptr) \
({ \
- __typeof__(*(ptr)) __user *__ptr_clean; \
- __ptr_clean = untagged_ptr(current->mm, ptr); \
might_fault(); \
- do_get_user_call(get_user,x,__ptr_clean); \
+ do_get_user_call(get_user,x,untagged_ptr(current->mm, ptr)); \
})
/**
@@ -263,10 +261,8 @@ extern void __put_user_nocheck_8(void);
* Return: zero on success, or -EFAULT on error.
*/
#define put_user(x, ptr) ({ \
- __typeof__(*(ptr)) __user *__ptr_clean; \
- __ptr_clean = untagged_ptr(current->mm, ptr); \
might_fault(); \
- do_put_user_call(put_user,x,__ptr_clean); \
+ do_put_user_call(put_user,x,untagged_ptr(current->mm, ptr)); \
})
/**
|