Re: [1/1][PATCH] nproc v2: netlink access to /proc information

Chris Wright
2004-09-14T21:23:18Z

* William Lee Irwin III (wli@holomorphy.com) wrote:
> On Tue, 14 Sep 2004 08:37:58 -0700, William Lee Irwin III wrote:
> >> No, in general races of the form "permissions were altered after I
> >> checked them" can happen.
>
> On Tue, Sep 14, 2004 at 06:01:50PM +0200, Roger Luethi wrote:
> > Can you make an example? Some scenario where this would be important?
>
> Not particularly. It largely means poorly-coded apps may report gibberish.

Canonical example is access(2) followed by open(2), not really relevant
in this case. However, exec setuid root app...when do you check, and
when to you fill in data to send back to user? For /proc, this type of
check happens often (see things like may_ptrace_attach and
task_dumpable in fs/proc/base.c).

thanks,
-chris
--
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