From 81f35ffde0e95ee18de83646bbf93dda55d9cc8b Mon Sep 17 00:00:00 2001 From: Philipp Zabel Date: Wed, 22 Oct 2014 16:34:35 +0200 Subject: [PATCH] net: fec: ptp: fix NULL pointer dereference if ptp_clock is not set Since commit 278d24047891 (net: fec: ptp: Enable PPS output based on ptp clock) fec_enet_interrupt calls fec_ptp_check_pps_event unconditionally, which calls into ptp_clock_event. If fep->ptp_clock is NULL, ptp_clock_event tries to dereference the NULL pointer. Since on i.MX53 fep->bufdesc_ex is not set, fec_ptp_init is never called, and fep->ptp_clock is NULL, which reliably causes a kernel panic. This patch adds a check for fep->ptp_clock == NULL in fec_enet_interrupt. Signed-off-by: Philipp Zabel Signed-off-by: David S. Miller --- drivers/net/ethernet/freescale/fec_main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c index 81b96cf87574..50a851db2852 100644 --- a/drivers/net/ethernet/freescale/fec_main.c +++ b/drivers/net/ethernet/freescale/fec_main.c @@ -1581,7 +1581,8 @@ fec_enet_interrupt(int irq, void *dev_id) complete(&fep->mdio_done); } - fec_ptp_check_pps_event(fep); + if (fep->ptp_clock) + fec_ptp_check_pps_event(fep); return ret; } -- 2.20.1