lkml.org 
[lkml]   [2010]   [Feb]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    SubjectRe: [PATCH] Restrict stack space reservation to rlimit
    From
    On Mon, Feb 8, 2010 at 2:05 PM, KOSAKI Motohiro
    <kosaki.motohiro@jp.fujitsu.com> wrote:
    >> --- linux-2.6-ozlabs.orig/fs/exec.c
    >> +++ linux-2.6-ozlabs/fs/exec.c
    >> @@ -627,10 +627,13 @@ int setup_arg_pages(struct linux_binprm
    >>                       goto out_unlock;
    >>       }
    >>
    >> +     stack_base = min(EXTRA_STACK_VM_PAGES * PAGE_SIZE,
    >> +                      current->signal->rlim[RLIMIT_STACK].rlim_cur -
    >> +                        PAGE_SIZE);
    >
    > This line is a bit unclear why "- PAGE_SIZE" is necessary.
    > personally, I like following likes explicit comments.
    >
    >        stack_expand = EXTRA_STACK_VM_PAGES * PAGE_SIZE;
    >        stack_lim = ACCESS_ONCE(rlim[RLIMIT_STACK].rlim_cur);
    >
    >        /* Initial stack must not cause stack overflow. */
    >        if (stack_expand + PAGE_SIZE > stack_lim)
    >                stack_expand = stack_lim - PAGE_SIZE;
    >
    > note: accessing rlim_cur require ACCESS_ONCE.
    >
    >
    > Thought?

    It's better to use the helper function: rlimit().
    --
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2010-02-08 08:11    [W:0.022 / U:0.292 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site