usercopy: fold builtin_const check into inline function
Instead of having each caller of check_object_size() need to remember to
check for a const size parameter, move the check into check_object_size()
itself. This actually matches the original implementation in PaX, though
this commit cleans up the now-redundant builtin_const() calls in the
various architectures.
Signed-off-by: Kees Cook <keescook@chromium.org>
diff --git a/arch/ia64/include/asm/uaccess.h b/arch/ia64/include/asm/uaccess.h
index 465c709..0472927 100644
--- a/arch/ia64/include/asm/uaccess.h
+++ b/arch/ia64/include/asm/uaccess.h
@@ -241,8 +241,7 @@
static inline unsigned long
__copy_to_user (void __user *to, const void *from, unsigned long count)
{
- if (!__builtin_constant_p(count))
- check_object_size(from, count, true);
+ check_object_size(from, count, true);
return __copy_user(to, (__force void __user *) from, count);
}
@@ -250,8 +249,7 @@
static inline unsigned long
__copy_from_user (void *to, const void __user *from, unsigned long count)
{
- if (!__builtin_constant_p(count))
- check_object_size(to, count, false);
+ check_object_size(to, count, false);
return __copy_user((__force void __user *) to, from, count);
}
@@ -265,8 +263,7 @@
long __cu_len = (n); \
\
if (__access_ok(__cu_to, __cu_len, get_fs())) { \
- if (!__builtin_constant_p(n)) \
- check_object_size(__cu_from, __cu_len, true); \
+ check_object_size(__cu_from, __cu_len, true); \
__cu_len = __copy_user(__cu_to, (__force void __user *) __cu_from, __cu_len); \
} \
__cu_len; \
@@ -280,8 +277,7 @@
\
__chk_user_ptr(__cu_from); \
if (__access_ok(__cu_from, __cu_len, get_fs())) { \
- if (!__builtin_constant_p(n)) \
- check_object_size(__cu_to, __cu_len, false); \
+ check_object_size(__cu_to, __cu_len, false); \
__cu_len = __copy_user((__force void __user *) __cu_to, __cu_from, __cu_len); \
} \
__cu_len; \