[net-next,v2,1/2] net: ethtool: Unify ETHTOOL_{G,S}RXFH rxnfc copy
Commit Message
ETHTOOL_GRXFH correctly copies in the full struct ethtool_rxnfc when
FLOW_RSS is set; ETHTOOL_SRXFH needs a similar code path to handle the
FLOW_RSS case so that ethtool can set the flow hash for custom RSS
contexts (if supported by the driver).
The copy code from ETHTOOL_GRXFH has been pulled out in to a helper so
that it can be called in both ETHTOOL_{G,S}RXFH code paths.
Acked-by: Edward Cree <ecree.xilinx@gmail.com>
Signed-off-by: Joe Damato <jdamato@fastly.com>
---
net/ethtool/ioctl.c | 75 +++++++++++++++++++++++----------------------
1 file changed, 38 insertions(+), 37 deletions(-)
@@ -907,6 +907,38 @@ static int ethtool_rxnfc_copy_to_compat(void __user *useraddr,
return 0;
}
+static int ethtool_rxnfc_copy_struct(u32 cmd, struct ethtool_rxnfc *info,
+ size_t *info_size, void __user *useraddr)
+{
+ /* struct ethtool_rxnfc was originally defined for
+ * ETHTOOL_{G,S}RXFH with only the cmd, flow_type and data
+ * members. User-space might still be using that
+ * definition.
+ */
+ if (cmd == ETHTOOL_GRXFH || cmd == ETHTOOL_SRXFH)
+ *info_size = (offsetof(struct ethtool_rxnfc, data) +
+ sizeof(info->data));
+
+ if (ethtool_rxnfc_copy_from_user(info, useraddr, *info_size))
+ return -EFAULT;
+
+ if ((cmd == ETHTOOL_GRXFH || cmd == ETHTOOL_SRXFH) && info->flow_type & FLOW_RSS) {
+ *info_size = sizeof(*info);
+ if (ethtool_rxnfc_copy_from_user(info, useraddr, *info_size))
+ return -EFAULT;
+ /* Since malicious users may modify the original data,
+ * we need to check whether FLOW_RSS is still requested.
+ */
+ if (!(info->flow_type & FLOW_RSS))
+ return -EINVAL;
+ }
+
+ if (info->cmd != cmd)
+ return -EINVAL;
+
+ return 0;
+}
+
static int ethtool_rxnfc_copy_to_user(void __user *useraddr,
const struct ethtool_rxnfc *rxnfc,
size_t size, const u32 *rule_buf)
@@ -944,16 +976,9 @@ static noinline_for_stack int ethtool_set_rxnfc(struct net_device *dev,
if (!dev->ethtool_ops->set_rxnfc)
return -EOPNOTSUPP;
- /* struct ethtool_rxnfc was originally defined for
- * ETHTOOL_{G,S}RXFH with only the cmd, flow_type and data
- * members. User-space might still be using that
- * definition. */
- if (cmd == ETHTOOL_SRXFH)
- info_size = (offsetof(struct ethtool_rxnfc, data) +
- sizeof(info.data));
-
- if (ethtool_rxnfc_copy_from_user(&info, useraddr, info_size))
- return -EFAULT;
+ rc = ethtool_rxnfc_copy_struct(cmd, &info, &info_size, useraddr);
+ if (rc)
+ return rc;
rc = dev->ethtool_ops->set_rxnfc(dev, &info);
if (rc)
@@ -978,33 +1003,9 @@ static noinline_for_stack int ethtool_get_rxnfc(struct net_device *dev,
if (!ops->get_rxnfc)
return -EOPNOTSUPP;
- /* struct ethtool_rxnfc was originally defined for
- * ETHTOOL_{G,S}RXFH with only the cmd, flow_type and data
- * members. User-space might still be using that
- * definition. */
- if (cmd == ETHTOOL_GRXFH)
- info_size = (offsetof(struct ethtool_rxnfc, data) +
- sizeof(info.data));
-
- if (ethtool_rxnfc_copy_from_user(&info, useraddr, info_size))
- return -EFAULT;
-
- /* If FLOW_RSS was requested then user-space must be using the
- * new definition, as FLOW_RSS is newer.
- */
- if (cmd == ETHTOOL_GRXFH && info.flow_type & FLOW_RSS) {
- info_size = sizeof(info);
- if (ethtool_rxnfc_copy_from_user(&info, useraddr, info_size))
- return -EFAULT;
- /* Since malicious users may modify the original data,
- * we need to check whether FLOW_RSS is still requested.
- */
- if (!(info.flow_type & FLOW_RSS))
- return -EINVAL;
- }
-
- if (info.cmd != cmd)
- return -EINVAL;
+ ret = ethtool_rxnfc_copy_struct(cmd, &info, &info_size, useraddr);
+ if (ret)
+ return ret;
if (info.cmd == ETHTOOL_GRXCLSRLALL) {
if (info.rule_cnt > 0) {