osf_getdomainname(): use copy_to_user()

commit 9ba3eb5103cf56f0daaf07de4507df76e7813ed7 upstream.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c
index 4f95577b01804422d0c5e55ce2856cb6b856dbcc..ddba64b46fe10f421f8994396d43144b66663906 100644 (file)
--- a/arch/alpha/kernel/osf_sys.c
+++ b/arch/alpha/kernel/osf_sys.c
@@ -561,25 +561,20 @@ SYSCALL_DEFINE0(getdtablesize)
  */
 SYSCALL_DEFINE2(osf_getdomainname, char __user *, name, int, namelen)
 {
-       unsigned len;
-       int i;
+       int len, err = 0;
+       char *kname;
 
-       if (!access_ok(VERIFY_WRITE, name, namelen))
-               return -EFAULT;
-
-       len = namelen;
-       if (len > 32)
-               len = 32;
+       if (namelen > 32)
+               namelen = 32;
 
        down_read(&uts_sem);
-       for (i = 0; i < len; ++i) {
-               __put_user(utsname()->domainname[i], name + i);
-               if (utsname()->domainname[i] == '\0')
-                       break;
-       }
+       kname = utsname()->domainname;
+       len = strnlen(kname, namelen);
+       if (copy_to_user(name, kname, min(len + 1, namelen)))
+               err = -EFAULT;
        up_read(&uts_sem);
 
-       return 0;
+       return err;
 }
 
 /*