| Message ID | 1464791961-8169-1-git-send-email-kjlu@gatech.edu |
|---|---|
| State | Rejected, archived |
| Delegated to: | David Miller |
| Headers | show |
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;
On Wed, 2016-06-01 at 16:39 +0200, Kangjie Lu wrote: > The field autoneg of pauseparam is not initialized in some > implementations of get_pauseparam(), Nonsense. The current implementation initialises all fields. (If there was padding in the structure, this change would be needed to guarantee that the padding was initialised. But there isn't.) Ben. > 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 > }; > + struct ethtool_pauseparam pauseparam; > + > + memset(&pauseparam, 0, sizeof(pauseparam)); > + pauseparam.cmd = ETHTOOL_GPAUSEPARAM; > > if (!dev->ethtool_ops->get_pauseparam) > return -EOPNOTSUPP;
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 }; + struct ethtool_pauseparam pauseparam; + + memset(&pauseparam, 0, sizeof(pauseparam)); + pauseparam.cmd = ETHTOOL_GPAUSEPARAM; if (!dev->ethtool_ops->get_pauseparam) return -EOPNOTSUPP;
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(-)