On Thu, 1 Jun 2017, Xishi Qiu wrote: Cc'ed John Stultz
> Hi, this is the test case, and then I got ubsan error > (signed integer overflow) report, so the root cause is from > user or kernel? Shall we change something in timeval_valid()? > > > struct itimerval new_value; > int ret; > > new_value.it_interval.tv_sec = 140673496649799L; > new_value.it_interval.tv_usec = 6; > new_value.it_value.tv_sec = 140673496649807L; > new_value.it_value.tv_usec = 5; > > ret = setitimer(ITIMER_VIRTUAL, &new_value, NULL); > > > [ 533.326588] > ================================================================================ > [ 533.335346] UBSAN: Undefined behaviour in ./include/linux/time.h:239:27 > [ 533.342155] signed integer overflow: > [ 533.345837] 140673496649807 * 1000000000 cannot be represented in type > 'long int' > [ 533.422181] set_cpu_itimer+0x49c/0x540 > [ 533.442127] do_setitimer+0xe1/0x540 We need a similar clamping of the conversion as we have for timespec/val_to_ktime(). I'll have a look in the next days unless John beats me to it. Thanks, tglx