[RFC][PATCH 10/14] xtensa: switch to providing csum_and_copy_from_user()

Al Viro
2020-03-27T23:31:30Z

arch/xtensa/include/asm/checksum.h | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/arch/xtensa/include/asm/checksum.h b/arch/xtensa/include/asm/checksum.h
index 8b687176ad72..d8292cc9ebdf 100644
--- a/arch/xtensa/include/asm/checksum.h
+++ b/arch/xtensa/include/asm/checksum.h
@@ -44,8 +44,6 @@ asmlinkage __wsum csum_partial_copy_generic(const void *src, void *dst,
/*
* Note: when you get a NULL pointer exception here this means someone
* passed in an incorrect kernel address to one of these functions.
- *
- * If you use these functions directly please don't forget the access_ok().
*/
static inline
__wsum csum_partial_copy_nocheck(const void *src, void *dst,
@@ -54,12 +52,17 @@ __wsum csum_partial_copy_nocheck(const void *src, void *dst,
return csum_partial_copy_generic(src, dst, len, sum, NULL, NULL);
}

+#define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
static inline
-__wsum csum_partial_copy_from_user(const void __user *src, void *dst,
+__wsum csum_and_copy_from_user(const void __user *src, void *dst,
int len, __wsum sum, int *err_ptr)
{
- return csum_partial_copy_generic((__force const void *)src, dst,
+ if (access_ok(dst, len))
+ return csum_partial_copy_generic((__force const void *)src, dst,
len, sum, err_ptr, NULL);
+ if (len)
+ *err_ptr = -EFAULT;
+ return sum;
}

/*
--
2.11.0