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    SubjectRe: [patch 2/2] posix-timers: Sanitize overrun handling
    On Tue, Jun 26, 2018 at 6:21 AM, Thomas Gleixner <tglx@linutronix.de> wrote:
    > The posix timer overrun handling is broken because the forwarding functions
    > can return a huge number of overruns which does not fit in an int. As a
    > consequence timer_getoverrun(2) and siginfo::si_overrun can turn into
    > random number generators.
    >
    > The k_clock::timer_forward() callbacks return a 64 bit value now. Make
    > k_itimer::ti_overrun[_last] 64bit as well, so the kernel internal
    > accounting is correct. 3Remove the temporary (int) casts.
    >
    > Add a helper function which clamps the overrun value returned to user space
    > via timer_getoverrun(2) or siginfo::si_overrun limited to a positive value
    > between 0 and INT_MAX. INT_MAX is an indicator for user space that the
    > overrun value has been clamped.
    >
    > Reported-by: air icy <icytxw@gmail.com>
    > Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

    Looks ok, and doesn't trip any regressions in testing so far.

    Acked-by: John Stultz <john.stultz@linaro.org>

    thanks
    -john

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