[Why]
There are several ns_to_ktime() calls that require using nanoseconds. It is
better to replace them with us_to_ktime() to make code clear, getting rid
of multiplication by 1000.
Also the timer function code may have an integer wrap-around issue. Since
both tx_custom_low_usecs and tx_custom_high_usecs can be set to up to
9999999 from the user space via cec_pin_error_inj_parse_line(), this may
cause usecs to be overflowed when adap->monitor_pin_cnt is zero and usecs
is multiplied by 1000.
[How]
Take advantage of using an appropriate helper func us_to_ktime() instead of
ns_to_ktime() to improve readability and to make the code clearer. And this
also mitigates possible integer wrap-arounds when usecs value is too large
and it is multiplied by 1000.
Found by Linux Verification Center (linuxtesting.org) with Svace.
Signed-off-by: Vitaliy Shevtsov <v.shevtsov@xxxxxxxxxxxxxxxxx>
---
v2: Wrapped some lines in the commit description to fit into 75 characters.
Reported by Patchwork Integration <patchwork@xxxxxxxxxxxx>
This patch was created after the Christophe JAILLET's comment at
https://lore.kernel.org/all/cff4d412-abbf-44b5-9705-ba14dff7d5d0@xxxxxxxxxx/
drivers/media/cec/core/cec-pin.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/drivers/media/cec/core/cec-pin.c b/drivers/media/cec/core/cec-pin.c
index a70451d99ebc..f232c3df7ee1 100644
--- a/drivers/media/cec/core/cec-pin.c
+++ b/drivers/media/cec/core/cec-pin.c
@@ -873,19 +873,19 @@ static enum hrtimer_restart cec_pin_timer(struct hrtimer *timer)
if (pin->wait_usecs > 150) {
pin->wait_usecs -= 100;
pin->timer_ts = ktime_add_us(ts, 100);
- hrtimer_forward_now(timer, ns_to_ktime(100000));
+ hrtimer_forward_now(timer, us_to_ktime(100));
return HRTIMER_RESTART;
}
if (pin->wait_usecs > 100) {
pin->wait_usecs /= 2;
pin->timer_ts = ktime_add_us(ts, pin->wait_usecs);
hrtimer_forward_now(timer,
- ns_to_ktime(pin->wait_usecs * 1000));
+ us_to_ktime(pin->wait_usecs));
return HRTIMER_RESTART;
}
pin->timer_ts = ktime_add_us(ts, pin->wait_usecs);
hrtimer_forward_now(timer,
- ns_to_ktime(pin->wait_usecs * 1000));
+ us_to_ktime(pin->wait_usecs));
pin->wait_usecs = 0;
return HRTIMER_RESTART;
}
@@ -1020,13 +1020,12 @@ static enum hrtimer_restart cec_pin_timer(struct hrtimer *timer)
if (!adap->monitor_pin_cnt || usecs <= 150) {
pin->wait_usecs = 0;
pin->timer_ts = ktime_add_us(ts, usecs);
- hrtimer_forward_now(timer,
- ns_to_ktime(usecs * 1000));
+ hrtimer_forward_now(timer, us_to_ktime(usecs));
return HRTIMER_RESTART;
}
pin->wait_usecs = usecs - 100;
pin->timer_ts = ktime_add_us(ts, 100);
- hrtimer_forward_now(timer, ns_to_ktime(100000));
+ hrtimer_forward_now(timer, us_to_ktime(100));
return HRTIMER_RESTART;
}
--
2.48.1
