can: dev: make can_change_state() robust to be called with cf == NULL

In OOM situations where no skb can be allocated, can_change_state() may
be called with cf == NULL. As this function updates the state and error
statistics it's not an option to skip the call to can_change_state() in
OOM situations.

This patch makes can_change_state() robust, so that it can be called
with cf == NULL.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
index 611d16a..ae4ed03 100644 (file)
--- a/drivers/net/can/dev.c
+++ b/drivers/net/can/dev.c
@@ -391,6 +391,9 @@ void can_change_state(struct net_device *dev, struct can_frame *cf,
        can_update_state_error_stats(dev, new_state);
        priv->state = new_state;
 
+       if (!cf)
+               return;
+
        if (unlikely(new_state == CAN_STATE_BUS_OFF)) {
                cf->can_id |= CAN_ERR_BUSOFF;
                return;