struct ethtool_rxnfc was originally defined in 2.6.27 for the
ETHTOOL_{G,S}RXFH command with only the cmd, flow_type and data
fields. It was then extended in 2.6.30 to support various additional
commands. These commands should have been defined to use a new
structure, but it is too late to change that now.
Since user-space may still be using the old structure definition
for the ETHTOOL_{G,S}RXFH commands, and since they do not need the
additional fields, only copy the originally defined fields to and
from user-space.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Cc: stable@kernel.org
---
include/linux/ethtool.h | 2 ++
net/core/ethtool.c | 36 +++++++++++++++++++++++++++---------
2 files changed, 29 insertions(+), 9 deletions(-)
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 2c8af09..07f9808 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -379,6 +379,8 @@ struct ethtool_rxnfc {
__u32 flow_type;
/* The rx flow hash value or the rule DB size */
__u64 data;
+ /* The following fields are not valid and must not be used for
+ * the ETHTOOL_{G,X}RXFH commands. */
struct ethtool_rx_flow_spec fs;
__u32 rule_cnt;
__u32 rule_locs[0];
diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index a3a7e9a..75e4ffe 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -318,23 +318,33 @@ out:
}
static noinline_for_stack int ethtool_set_rxnfc(struct net_device *dev,
- void __user *useraddr)
+ u32 cmd, void __user *useraddr)
{
- struct ethtool_rxnfc cmd;
+ struct ethtool_rxnfc info;
+ size_t info_size = sizeof(info);
if (!dev->ethtool_ops->set_rxnfc)
return -EOPNOTSUPP;
- if (copy_from_user(&cmd, useraddr, sizeof(cmd)))
+ /* 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 = ...
