On Wed, Jun 03, 2015 at 10:47:42AM +0200, Jan Kara wrote: > On Wed 03-06-15 09:50:30, Martin Schwidefsky wrote: > > On Tue, 2 Jun 2015 17:07:33 +0200 > > Jan Kara <jack@xxxxxxx> wrote: > > > > > strnlen_user() returns the length of the string including terminating 0. > > > So avoid counting it again and unnecessarily reducing maximum string > > > size by 1. > > > > > > CC: Heiko Carstens <heiko.carstens@xxxxxxxxxx> > > > Signed-off-by: Jan Kara <jack@xxxxxxx> [...] > > > > The simplification with the string length is nice but removing > > the explicit NUL termination is imho a mistake. Who guarantees > > you that the string in user space is still the same after the > > initial strnlen_user? It might have changed before the > > copy_from_user call and then we end up with an unterminated > > string in the kernel. Not good. > Ah, that's a good point. Thanks for catching this. But it would deserve > a comment in the code. Attached is an updated patch. Nice ;) I applied your updated patch instead. Thanks! -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
