alpha: fix copy_from_user()

it should clear the destination even when access_ok() fails.

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2016-08-17 16:02:32 -04:00
parent 694d0d0bb2
commit 2561d309df

View File

@ -371,14 +371,6 @@ __copy_tofrom_user_nocheck(void *to, const void *from, long len)
return __cu_len;
}
extern inline long
__copy_tofrom_user(void *to, const void *from, long len, const void __user *validate)
{
if (__access_ok((unsigned long)validate, len, get_fs()))
len = __copy_tofrom_user_nocheck(to, from, len);
return len;
}
#define __copy_to_user(to, from, n) \
({ \
__chk_user_ptr(to); \
@ -393,17 +385,22 @@ __copy_tofrom_user(void *to, const void *from, long len, const void __user *vali
#define __copy_to_user_inatomic __copy_to_user
#define __copy_from_user_inatomic __copy_from_user
extern inline long
copy_to_user(void __user *to, const void *from, long n)
{
return __copy_tofrom_user((__force void *)to, from, n, to);
if (likely(__access_ok((unsigned long)to, n, get_fs())))
n = __copy_tofrom_user_nocheck((__force void *)to, from, n);
return n;
}
extern inline long
copy_from_user(void *to, const void __user *from, long n)
{
return __copy_tofrom_user(to, (__force void *)from, n, from);
if (likely(__access_ok((unsigned long)from, n, get_fs())))
n = __copy_tofrom_user_nocheck(to, (__force void *)from, n);
else
memset(to, 0, n);
return n;
}
extern void __do_clear_user(void);