07 Nov, 2015

1 commit

  • setpriority(PRIO_USER, 0, x) will change the priority of tasks outside of
    the current pid namespace. This is in contrast to both the other modes of
    setpriority and the example of kill(-1). Fix this. getpriority and
    ioprio have the same failure mode, fix them too.

    Eric said:

    : After some more thinking about it this patch sounds justifiable.
    :
    : My goal with namespaces is not to build perfect isolation mechanisms
    : as that can get into ill defined territory, but to build well defined
    : mechanisms. And to handle the corner cases so you can use only
    : a single namespace with well defined results.
    :
    : In this case you have found the two interfaces I am aware of that
    : identify processes by uid instead of by pid. Which quite frankly is
    : weird. Unfortunately the weird unexpected cases are hard to handle
    : in the usual way.
    :
    : I was hoping for a little more information. Changes like this one we
    : have to be careful of because someone might be depending on the current
    : behavior. I don't think they are and I do think this make sense as part
    : of the pid namespace.

    Signed-off-by: Ben Segall
    Cc: Oleg Nesterov
    Cc: Al Viro
    Cc: Ambrose Feinstein
    Acked-by: "Eric W. Biederman"
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ben Segall
     

31 Oct, 2014

1 commit

  • Priority of a merged request is computed by ioprio_best(). If one of the
    requests has undefined priority (IOPRIO_CLASS_NONE) and another request
    has priority from IOPRIO_CLASS_BE, the function will return the
    undefined priority which is wrong. Fix the function to properly return
    priority of a request with the defined priority.

    Fixes: d58cdfb89ce0c6bd5f81ae931a984ef298dbda20
    CC: stable@vger.kernel.org
    Signed-off-by: Jan Kara
    Reviewed-by: Jeff Moyer
    Signed-off-by: Jens Axboe

    Jan Kara
     

20 May, 2014

1 commit