From: Philipp Zabel Date: Wed, 22 Oct 2014 14:34:35 +0000 (+0200) Subject: net: fec: ptp: fix NULL pointer dereference if ptp_clock is not set X-Git-Tag: firefly_0821_release~176^2~2938^2~45 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=81f35ffde0e95ee18de83646bbf93dda55d9cc8b;p=firefly-linux-kernel-4.4.55.git 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 --- 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; }