ia64: copy_from_user() should zero the destination on access_ok() failure

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2016-08-18 21:31:41 -04:00
parent f35c1e0671
commit a5e541f796

View file

@ -272,20 +272,17 @@ __copy_from_user (void *to, const void __user *from, unsigned long count)
__cu_len; \
})
#define copy_from_user(to, from, n) \
({ \
void *__cu_to = (to); \
const void __user *__cu_from = (from); \
long __cu_len = (n); \
\
__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); \
__cu_len = __copy_user((__force void __user *) __cu_to, __cu_from, __cu_len); \
} \
__cu_len; \
})
static inline unsigned long
copy_from_user(void *to, const void __user *from, unsigned long n)
{
if (!__builtin_constant_p(n))
check_object_size(to, n, false);
if (likely(__access_ok(from, n, get_fs())))
n = __copy_user((__force void __user *) to, from, n);
else
memset(to, 0, n);
return n;
}
#define __copy_in_user(to, from, size) __copy_user((to), (from), (size))