Messages in this thread |  | | From | (Miquel van Smoorenburg) | Subject | Re: As 2.0 looms | Date | Wed, 22 May 1996 20:36:54 +0200 (MET DST) |
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In article <m0uHYnS-0005FhC@lightning.swansea.linux.org.uk>, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote: >> Nope, there is no window, because the read() actually checks the same >> things that "ptrace" checks. Notably, in order to be able to read the >> process memory map, we must have the PF_PTRACED bit set, and then a suid >> execve wouldn't succeed anyway. > >It depends when the read tests, we could start the read have PF_TRACED turn off >and then exec a setuid program. If the read tests per byte we should be ok.
How Alan? The only process that can turn off the trace bit _is_ the process doing the reading/mmaping...
Mike. -- + Miquel van Smoorenburg + Cistron Internet Services + Living is a | | miquels@cistron.nl (SP6) | Independent Dutch ISP | horizontal | + miquels@drinkel.ow.org + http://www.cistron.nl/ + fall +
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