Provide conveniance wrappers around scoped masked user access similiar to
put/get_user(), which reduce the usage sites to:
if (!get_user_masked(val, ptr))
return -EFAULT;
Signed-off-by: Thomas Gleixner <[email protected]>
---
include/linux/uaccess.h | 44 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 44 insertions(+)
--- a/include/linux/uaccess.h
+++ b/include/linux/uaccess.h
@@ -830,6 +830,50 @@ for (bool ____stop = false; !____stop; _
#define scoped_masked_user_rw_access(_uptr, _elbl)
\
scoped_masked_user_rw_access_size((_uptr), sizeof(*(_uptr)), _elbl)
+/**
+ * get_user_masked - Read user data with masked access
+ * @_val: The variable to store the value read from user memory
+ * @_usrc: Pointer to the user space memory to read from
+ *
+ * Return: true if successful, false when faulted
+ */
+#define get_user_masked(_val, _usrc) \
+({ \
+ __label__ efault; \
+ typeof((_usrc)) _tmpsrc = (_usrc); \
+ bool ____ret = true; \
+ \
+ scoped_masked_user_read_access(_tmpsrc, efault) \
+ unsafe_get_user(_val, _tmpsrc, efault); \
+ if (0) { \
+ efault: \
+ ____ret = false; \
+ } \
+ ____ret; \
+})
+
+/**
+ * put_user_masked - Write to user memory with masked access
+ * @_val: The value to write
+ * @_udst: Pointer to the user space memory to write to
+ *
+ * Return: true if successful, false when faulted
+ */
+#define put_user_masked(_val, _udst) \
+({ \
+ __label__ efault; \
+ typeof((_udst)) _tmpdst = (_udst); \
+ bool ____ret = true; \
+ \
+ scoped_masked_user_write_access(_tmpdst, efault) \
+ unsafe_put_user(_val, _tmpdst, efault); \
+ if (0) { \
+ efault: \
+ ____ret = false; \
+ } \
+ ____ret; \
+})
+
#ifdef CONFIG_HARDENED_USERCOPY
void __noreturn usercopy_abort(const char *name, const char *detail,
bool to_user, unsigned long offset,
