From: Tom Horsley <horsley1953@gmail.com>
To: linux-kernel@vger.kernel.org
Subject: ptrace versus setuid changes in 4.14?
Date: Thu, 21 Dec 2017 09:18:11 -0500 [thread overview]
Message-ID: <20171221091811.5bbb47db@tomh> (raw)
On my fedora 26 box with a 4.13 kernel, when a process
under ptrace control did an exec of a setuid program,
the program lost all of its setuid privileges and
ptrace could operate on it like a normal program.
Experimental evidence seems to indicate that on
fedora 27 with a 4.14 kernel, ptrace cannot
do a PEEKDATA to read anything from the just
execed setuid program. (I get errno 5 - I/O error).
Am I confused somehow, or did something really change
in this vicinity?
It puts a real crimp in my fancy debug feature to
patch code into a setuid program to make it re-exec itself,
then detach from it. (I don't suppose we could get
a setoptions feature to tell the kernel to detach
from setuid programs automagically and let the debugger
know it is no longer in control of the process?)
next reply other threads:[~2017-12-21 14:18 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-12-21 14:18 Tom Horsley [this message]
2017-12-22 20:28 ` ptrace versus setuid changes in 4.14? Laura Abbott
2017-12-22 20:55 ` Tom Horsley
2017-12-22 23:14 ` Kees Cook
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