linux-kernel - [PATCH v1] ptp: ocp: fix start time alignment in ptp_ocp_signal

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250414143220.121657-1-maimon.sagi@gmail.com>
Date: Mon, 14 Apr 2025 17:32:20 +0300
From: Sagi Maimon <maimon.sagi@...il.com>
To: jonathan.lemon@...il.com,
	vadim.fedorenko@...ux.dev,
	richardcochran@...il.com,
	andrew+netdev@...n.ch,
	davem@...emloft.net,
	edumazet@...gle.com,
	kuba@...nel.org,
	pabeni@...hat.com
Cc: linux-kernel@...r.kernel.org,
	netdev@...r.kernel.org,
	Sagi Maimon <maimon.sagi@...il.com>
Subject: [PATCH v1] ptp: ocp: fix start time alignment in ptp_ocp_signal_set

In ptp_ocp_signal_set, the start time for periodic signals is not
aligned to the next period boundary. The current code rounds up the
start time and divides by the period but fails to multiply back by
the period, causing misaligned signal starts. Fix this by multiplying
the rounded-up value by the period to ensure the start time is the
closest next period.

Fixes: 4bd46bb037f8e ("ptp: ocp: Use DIV64_U64_ROUND_UP for rounding.")
Signed-off-by: Sagi Maimon <maimon.sagi@...il.com>
---
 drivers/ptp/ptp_ocp.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/ptp/ptp_ocp.c b/drivers/ptp/ptp_ocp.c
index 7945c6be1f7c..e5b55b78a6d7 100644
--- a/drivers/ptp/ptp_ocp.c
+++ b/drivers/ptp/ptp_ocp.c
@@ -2067,6 +2067,7 @@ ptp_ocp_signal_set(struct ptp_ocp *bp, int gen, struct ptp_ocp_signal *s)
 	if (!s->start) {
 		/* roundup() does not work on 32-bit systems */
 		s->start = DIV64_U64_ROUND_UP(start_ns, s->period);
+		s->start = (s->start) * (s->period);
 		s->start = ktime_add(s->start, s->phase);
 	}
 
-- 
2.47.0