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Date: Thu, 11 Aug 2011 23:50:34 +0400
From: Vasiliy Kulikov <segoon@openwall.com>
To: linux-kernel@vger.kernel.org, Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>, Ben Hutchings <ben@decadent.org.uk>,
        Christian Ohm <chr.ohm@gmx.net>, David Ahern <dsahern@gmail.com>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Jonathan Nieder <jrnieder@gmail.com>, Mike Galbraith <efault@gmx.de>,
        Paul Mackerras <paulus@samba.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Stephane Eranian <eranian@google.com>
Subject: re: perf tools: Check $HOME/.perfconfig ownership
Message-ID: <20110811195033.GA17313@albatros>
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Hi,

The commit 069e3725dd9be3b759a98e8c80ac5fc38b392b23 introduced a check
whether $HOME/.perfconfig file is owned by the user.  Three comments here:

1) How other user may create a file in other user's home directory?  If
we assume he may do it, the situation is bad without any perf :(

2) If we assume (1) is somehow possible (e.g. other user may manipulate
this file only), there is a race against file creation/deletion and stat.

3) .perfconfig can be a symlink, so stat(2) should be changed to
lstat(2).


Thanks,

-- 
Vasiliy