[Coverity CID :195871]Integer handling issues in /drivers/counter/counter_ll_stm32_rtc.c

[aasthagr]

Static code scan issues seen in File: /drivers/counter/counter_ll_stm32_rtc.c
Category: Integer handling issues
Function: rtc_stm32_read
Component: Drivers
CID: 195871
Please fix or provide comments to square it off in coverity in the link: https://scan9.coverity.com/reports.htm#v32951/p12996

[erwango]

Cf analysis in #14415.
Will be fixed when upgrading SDK to 0.10.0.

[ceolin]

@erwango actually coverity spot this problem even with latest sdk. Question, why don't you cast this way:

ticks = counter_us_to_ticks(dev, (u64_t)ts * USEC_PER_SEC);

Here the we ensure that the multiplication won't overflow

[ceolin]

actually you don't need the cast at all, ts is time_t

[ceolin]

#14799

[erwango]

@ceolin , cf my comment in #14799, none of the proposal works actually.