Re: As 2.0 looms

Miquel van Smoorenburg (miquels@drinkel.ow.org)
Tue, 21 May 1996 11:41:02 +0200 (MET DST)


In article <m0uGULF-0005FhC@lightning.swansea.linux.org.uk>,
Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
>> Quick fix in .96, but breaks at least some versions of strace. Changed
>> in .98 - strace works again, but I think there may be a race condition
>> if read() passes the checks, sleeps on memcpy_tofs() due to a swap-in,
>> and the target process execs a setuid program in this time window.
>
>Thats bad because with an nfs program and a PC on the lan you can use for
>flooding it becomes quite a wide window.

No the target program must be PTRACE_ATTACHed and it must also be
in a _stopped_ state. So there is no way for it to continue
running and do an exec or whatever.

Mike.

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