Messages in this thread | | | Subject | Re: [PATCH] ethtool: fix a kernel infoleak in ethtool_get_pauseparam | From | Edward Cree <> | Date | Wed, 1 Jun 2016 15:57:33 +0100 |
| |
On 01/06/16 15:39, Kangjie Lu wrote: > The field autoneg of pauseparam is not initialized in some > implementations of get_pauseparam(), but the whole object is > copied to userland. > > Signed-off-by: Kangjie Lu <kjlu@gatech.edu> > --- > net/core/ethtool.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/net/core/ethtool.c b/net/core/ethtool.c > index f426c5a..84544bd 100644 > --- a/net/core/ethtool.c > +++ b/net/core/ethtool.c > @@ -1723,7 +1723,10 @@ static noinline_for_stack int ethtool_set_channels(struct net_device *dev, > > static int ethtool_get_pauseparam(struct net_device *dev, void __user *useraddr) > { > - struct ethtool_pauseparam pauseparam = { ETHTOOL_GPAUSEPARAM }; AIUI an incomplete compound initialiser will fill all unspecified fields with zeroes of the appropriate type. So this patch is unnecessary.
Per C99, §6.7.8.21: > If there are fewer initializers in a brace-enclosed list than there are elements or members of an aggregate [...] the remainder of the aggregate shall be initialized implicitly the same as objects that have static storage duration.
-Ed
> + struct ethtool_pauseparam pauseparam; > + > + memset(&pauseparam, 0, sizeof(pauseparam)); > + pauseparam.cmd = ETHTOOL_GPAUSEPARAM; > > if (!dev->ethtool_ops->get_pauseparam) > return -EOPNOTSUPP;
| |