In the Linux kernel, the following vulnerability has been resolved: rtc: tps6594: Fix integer overflow on 32bit systems The problem is this multiply in tps6594_rtc_set_offset() tmp = offset * TICKS_PER_HOUR; The "tmp" variable is an s64 but "offset" is a long in the (-277774)-277774 range. On 32bit systems a long can hold numbers up to approximately two billion. The number of TICKS_PER_HOUR is really large, (32768 * 3600) or roughly a hundred million. When you start multiplying by a hundred million it doesn't take long to overflow the two billion mark. Probably the safest way to fix this is to change the type of TICKS_PER_HOUR to long long because it's such a large number.
The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.