On Wed, Oct 30, 2013 at 07:31:06AM +0000, Winkler, Tomas wrote: > > > > > --- > > > drivers/misc/mei/hbm.c | 6 ++++-- > > > 1 file changed, 4 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/misc/mei/hbm.c b/drivers/misc/mei/hbm.c > > > index 9b3a0fb..0f5e8ca 100644 > > > --- a/drivers/misc/mei/hbm.c > > > +++ b/drivers/misc/mei/hbm.c > > > @@ -228,8 +228,6 @@ static int mei_hbm_prop_req(struct mei_device *dev) > > > unsigned long client_num; > > > > > > > > > - client_num = dev->me_client_presentation_num; > > > - > > > next_client_index = find_next_bit(dev->me_clients_map, > > MEI_CLIENTS_MAX, > > > dev->me_client_index); > > > > > > @@ -241,6 +239,10 @@ static int mei_hbm_prop_req(struct mei_device *dev) > > > return 0; > > > } > > > > > > + client_num = dev->me_client_presentation_num; > > > + if (WARN_ON(dev->me_clients_num <= client_num)) > > > + return -EIO; > > > > How can this happen? Why is spitting out a huge warning in the syslog > > going to help anything? If a user can do this, then great, now you can > > DoS your syslog :( > > > > If a user can't do this, then why tell them, it's your driver's bug that > > you should just fix. > > This somehow should guard buffer overflow allocated of size > dev->me_clients_num > In theory this can happen only if something go wrong in hardware > initialization or there is some other security hole that can change > client_num.
What _kind_ of "security hole" could ever change that number? Where does it come from? Who can modify it? If you don't know that now then we have worse problems... greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/