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    SubjectRe: select() for delay.
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    Date
    On Mon, 2005-10-24 at 15:27 +0200, Arjan van de Ven wrote:
    > On Mon, 2005-10-24 at 09:18 -0400, Steven Rostedt wrote:
    > > Hi Maduhu,
    > >
    > > On Mon, 2005-10-24 at 16:25 +0530, madhu.subbaiah@wipro.com wrote:
    > >
    > > > + put_user(sec, &tvp->tv_sec);
    > > > + put_user(usec, &tvp->tv_usec);
    > >
    > > I won't comment on the rest of the patch, but this part is definitely
    > > wrong. The pointer tvp is a user space address and once you dereference
    > > that pointer to get to tv_sec, you can have a fault, which might
    > > segfault the
    >
    > &pointer->member doesn't dereference the pointer, it just adds the
    > offset of "member" to the content of the pointer.
    >

    Oh crap! You're right ;-)

    Argh, that's what I get for replying before my first cup of coffee and
    suffering jet lag.

    I should have known this since I just copied over the container_of macro
    to a user process, and if what I said was true, ((type *)0)->member
    would never work.

    Oh well, time to wake up :-)

    -- Steve




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