From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Gustavo A. R. Silva" Subject: [PATCH] net: dsa: mv88e6xxx: hwtstamp: fix potential negative array index read Date: Thu, 15 Feb 2018 12:10:05 -0600 Message-ID: <20180215181005.GA21263@embeddedor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" To: Brandon Streiff , Andrew Lunn , Vivien Didelot , Florian Fainelli Return-path: Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org _port_ is being used as index to array port_hwtstamp before verifying it is a non-negative number and a valid index at 209: if (port < 0 || port >= mv88e6xxx_num_ports(chip)) Fix this by checking _port_ before using it as index to array port_hwtstamp. Addresses-Coverity-ID: 1465287 ("Negative array index read") Fixes: c6fe0ad2c349 ("net: dsa: mv88e6xxx: add rx/tx timestamping support") Signed-off-by: Gustavo A. R. Silva --- drivers/net/dsa/mv88e6xxx/hwtstamp.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/net/dsa/mv88e6xxx/hwtstamp.c b/drivers/net/dsa/mv88e6xxx/hwtstamp.c index b251d53..761decc 100644 --- a/drivers/net/dsa/mv88e6xxx/hwtstamp.c +++ b/drivers/net/dsa/mv88e6xxx/hwtstamp.c @@ -200,8 +200,8 @@ int mv88e6xxx_port_hwtstamp_get(struct dsa_switch *ds, int port, struct ifreq *ifr) { struct mv88e6xxx_chip *chip = ds->priv; - struct mv88e6xxx_port_hwtstamp *ps = &chip->port_hwtstamp[port]; - struct hwtstamp_config *config = &ps->tstamp_config; + struct mv88e6xxx_port_hwtstamp *ps; + struct hwtstamp_config *config; if (!chip->info->ptp_support) return -EOPNOTSUPP; @@ -209,6 +209,9 @@ int mv88e6xxx_port_hwtstamp_get(struct dsa_switch *ds, int port, if (port < 0 || port >= mv88e6xxx_num_ports(chip)) return -EINVAL; + ps = &chip->port_hwtstamp[port]; + config = &ps->tstamp_config; + return copy_to_user(ifr->ifr_data, config, sizeof(*config)) ? -EFAULT : 0; } -- 2.7.4