ptp: Add error handling for adjfine callback in ptp_clock_adjtime

[ Upstream commit 98337d7c87577ded71114f6976edb70a163e27bc ]

ptp_clock_adjtime sets ptp->dialed_frequency even when adjfine
callback returns an error. This causes subsequent reads to return
an incorrect value.

Fix this by adding error check before ptp->dialed_frequency is set.

Fixes: 39a8cbd9ca05 ("ptp: remember the adjusted frequency")
Signed-off-by: Ajay Kaher <ajay.kaher@broadcom.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Link: https://patch.msgid.link/20241125105954.1509971-1-ajay.kaher@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
index e70c6dec3a3a3806acbebfd5594bfb1c2767a546..92dd1c6f54f4a607dbb4c30ccc705e0b918c8f83 100644 (file)
--- a/drivers/ptp/ptp_clock.c
+++ b/drivers/ptp/ptp_clock.c
@@ -136,7 +136,8 @@ static int ptp_clock_adjtime(struct posix_clock *pc, struct __kernel_timex *tx)
                        err = ops->adjfine(ops, tx->freq);
                else
                        err = ops->adjfreq(ops, ppb);
-               ptp->dialed_frequency = tx->freq;
+               if (!err)
+                       ptp->dialed_frequency = tx->freq;
        } else if (tx->modes & ADJ_OFFSET) {
                if (ops->adjphase) {
                        s32 offset = tx->offset;