[PATCH 5.4 74/92] net: mscc: ocelot: dont downgrade timestamping RX filters in SIOCSHWTSTAMP

From: Greg Kroah-Hartman
Date: Mon Nov 29 2021 - 17:34:56 EST


From: Vladimir Oltean <vladimir.oltean@xxxxxxx>

[ Upstream commit 8a075464d1e9317ffae0973dfe538a7511291a06 ]

The ocelot driver, when asked to timestamp all receiving packets, 1588
v1 or NTP, says "nah, here's 1588 v2 for you".

According to this discussion:
https://patchwork.kernel.org/project/netdevbpf/patch/20211104133204.19757-8-martin.kaistra@xxxxxxxxxxxxx/#24577647
drivers that downgrade from a wider request to a narrower response (or
even a response where the intersection with the request is empty) are
buggy, and should return -ERANGE instead. This patch fixes that.

Fixes: 4e3b0468e6d7 ("net: mscc: PTP Hardware Clock (PHC) support")
Suggested-by: Richard Cochran <richardcochran@xxxxxxxxx>
Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
Acked-by: Richard Cochran <richardcochran@xxxxxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/mscc/ocelot.c | 6 ------
1 file changed, 6 deletions(-)

diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c
index 6030c90d50ccb..3f83647c5802e 100644
--- a/drivers/net/ethernet/mscc/ocelot.c
+++ b/drivers/net/ethernet/mscc/ocelot.c
@@ -1024,12 +1024,6 @@ static int ocelot_hwstamp_set(struct ocelot_port *port, struct ifreq *ifr)
switch (cfg.rx_filter) {
case HWTSTAMP_FILTER_NONE:
break;
- case HWTSTAMP_FILTER_ALL:
- case HWTSTAMP_FILTER_SOME:
- case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
- case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
- case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
- case HWTSTAMP_FILTER_NTP_ALL:
case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
--
2.33.0