> > --- > > 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. After this happen you probably won't be able to use the driver anyhow so I do not expect DoS on the syslog, but we can drop the WARN_ON but I would stick with the check Thanks Tomas -- 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/
