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Cosmin Tanislav
c0b1da281d
Switch to u64 arithmetic and use DIV_ROUND_CLOSEST_ULL() to avoid the overflow. buffer[i] is unsigned int and is limited by the lirc core to IR_MAX_DURATION, which is 500000. idata->freq is u32, which has a max value of 0xFFFFFFFF. In the case where buffer[i] is 500000, idata->freq overflows the u32 multiplication for any values >= 8590. 0xFFFFFFFF / 500000 ~= 8589 By casting buffer[i] to u64, idata->freq can be any u32 value without overflowing the multiplication. 0xFFFFFFFFFFFFFFFF / 500000 ~= 36893488147419 (> 4294967295) The result of the final operation will fit back into the unsigned int limits without any issues. 500000 * 0xFFFFFFFF / 1000000 = 0x80000000 (< 0xFFFFFFFF) Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com> Signed-off-by: Sean Young <sean@mess.org> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>