4.16-stable review patch. If anyone has any objections, please let me know.
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From: Andrew Lunn andrew@lunn.ch
[ Upstream commit fc5f33768cca7144f8d793205b229d46740d183b ]
The Marvell switches under some conditions will pass a frame to the host with the port being the CPU port. Such frames are invalid, and should be dropped. Not dropping them can result in a crash when incrementing the receive statistics for an invalid port.
Reported-by: Chris Healy cphealy@gmail.com Fixes: 91da11f870f0 ("net: Distributed Switch Architecture protocol support") Signed-off-by: Andrew Lunn andrew@lunn.ch Reviewed-by: Florian Fainelli f.fainelli@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/dsa/dsa_priv.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
--- a/net/dsa/dsa_priv.h +++ b/net/dsa/dsa_priv.h @@ -126,6 +126,7 @@ static inline struct net_device *dsa_mas struct dsa_port *cpu_dp = dev->dsa_ptr; struct dsa_switch_tree *dst = cpu_dp->dst; struct dsa_switch *ds; + struct dsa_port *slave_port;
if (device < 0 || device >= DSA_MAX_SWITCHES) return NULL; @@ -137,7 +138,12 @@ static inline struct net_device *dsa_mas if (port < 0 || port >= ds->num_ports) return NULL;
- return ds->ports[port].slave; + slave_port = &ds->ports[port]; + + if (unlikely(slave_port->type != DSA_PORT_TYPE_USER)) + return NULL; + + return slave_port->slave; }
/* port.c */