sfc: check for NULL efx->ptp_data in efx_ptp_event

ecree-solarflare · davem330 · commit 8f355e5cee63 · 2014-02-26T15:22:02.000-05:00
If we receive a PTP event from the NIC when we haven't set up PTP state
in the driver, we attempt to read through a NULL pointer efx-&gt;ptp_data,
triggering a panic.

Signed-off-by: Edward Cree &lt;ecree@solarflare.com&gt;
Acked-by: Shradha Shah &lt;sshah@solarflare.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
diff --git a/drivers/net/ethernet/sfc/ptp.c b/drivers/net/ethernet/sfc/ptp.c
@@ -1668,6 +1668,13 @@ void efx_ptp_event(struct efx_nic *efx, efx_qword_t *ev)
 	struct efx_ptp_data *ptp = efx->ptp_data;
 	int code = EFX_QWORD_FIELD(*ev, MCDI_EVENT_CODE);
 
+	if (!ptp) {
+		if (net_ratelimit())
+			netif_warn(efx, drv, efx->net_dev,
+				   "Received PTP event but PTP not set up\n");
+		return;
+	}
+
 	if (!ptp->enabled)
 		return;
 
