The following commit has been merged into the timers/urgent branch of tip:
Commit-ID: 299130166e70124956c865a66a3669a61db1c212
Gitweb: https://git.kernel.org/tip/299130166e70124956c865a66a3669a61db1c212
Author: Marcelo Dalmas <marcelo.dalmas@xxxxxx>
AuthorDate: Mon, 25 Nov 2024 12:16:09
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Wed, 27 Nov 2024 15:18:45 +01:00
ntp: Remove invalid cast in time offset math
Due to an unsigned cast, adjtimex() returns the wrong offest when using
ADJ_MICRO and the offset is negative. In this case a small negative offset
returns approximately 4.29 seconds (~ 2^32/1000 milliseconds) due to the
unsigned cast of the negative offset.
Remove the cast and restore the signed division to cure that issue.
Fixes: ead25417f82e ("timex: use __kernel_timex internally")
Signed-off-by: Marcelo Dalmas <marcelo.dalmas@xxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/all/SJ0P101MB03687BF7D5A10FD3C49C51E5F42E2@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
---
kernel/time/ntp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index b550ebe..02e7fe6 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -798,7 +798,7 @@ int __do_adjtimex(struct __kernel_timex *txc, const struct timespec64 *ts,
txc->offset = shift_right(ntpdata->time_offset * NTP_INTERVAL_FREQ, NTP_SCALE_SHIFT);
if (!(ntpdata->time_status & STA_NANO))
- txc->offset = (u32)txc->offset / NSEC_PER_USEC;
+ txc->offset /= NSEC_PER_USEC;
}
result = ntpdata->time_state;
|