From 51d58c0c7921d3c93c44099b90dc46720d095bde Mon Sep 17 00:00:00 2001 From: Jacob Keller Date: Wed, 12 Mar 2025 15:15:51 -0700 Subject: [PATCH] renesas: reject PTP_STRICT_FLAGS as unsupported MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The ravb_ptp_extts() function checks the flags coming from the PTP_EXTTS_REQUEST ioctl, to ensure that future flags are not accepted on accident. This was updated to 'honor' the PTP_STRICT_FLAGS in commit 6138e687c7b6 ("ptp: Introduce strict checking of external time stamp options."). However, the driver does not *actually* validate the flags. I originally fixed this driver to reject future flags in commit 592025a03b34 ("renesas: reject unsupported external timestamp flags"). It is still unclear whether this hardware timestamps the rising, falling, or both edges of the input signal. Accepting requests with PTP_STRICT_FLAGS is a bug, as this could lead to users mistakenly assuming a request with PTP_RISING_EDGE actually timestamps the rising edge only. Reject requests with PTP_STRICT_FLAGS (and hence all PTP_EXTTS_REQUEST2 requests) until someone with access to the datasheet or hardware knowledge can confirm the timestamping behavior and update this driver. Fixes: 6138e687c7b6 ("ptp: Introduce strict checking of external time stamp options.") Signed-off-by: Jacob Keller Reviewed-by: Niklas Söderlund Reviewed-by: Simon Horman Link: https://patch.msgid.link/20250312-jk-net-fixes-supported-extts-flags-v2-2-ea930ba82459@intel.com Signed-off-by: Paolo Abeni --- drivers/net/ethernet/renesas/ravb_ptp.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/net/ethernet/renesas/ravb_ptp.c b/drivers/net/ethernet/renesas/ravb_ptp.c index 6e4ef7af27bf3..b4365906669f3 100644 --- a/drivers/net/ethernet/renesas/ravb_ptp.c +++ b/drivers/net/ethernet/renesas/ravb_ptp.c @@ -179,8 +179,7 @@ static int ravb_ptp_extts(struct ptp_clock_info *ptp, /* Reject requests with unsupported flags */ if (req->flags & ~(PTP_ENABLE_FEATURE | PTP_RISING_EDGE | - PTP_FALLING_EDGE | - PTP_STRICT_FLAGS)) + PTP_FALLING_EDGE)) return -EOPNOTSUPP; if (req->index)