From: Olaf Hering <olaf@aepfle.de>
To: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>,
Ian Jackson <Ian.Jackson@eu.citrix.com>,
Ian Campbell <Ian.Campbell@citrix.com>,
Xen-devel <xen-devel@lists.xen.org>
Subject: Re: [PATCH for-4.5] tools/pygrub: Fix TOCTOU race introduced by c/s 63dcc68
Date: Wed, 29 Oct 2014 20:43:04 +0100 [thread overview]
Message-ID: <20141029194304.GA1606@aepfle.de> (raw)
In-Reply-To: <54512D5B.1040003@citrix.com>
On Wed, Oct 29, Andrew Cooper wrote:
> The result is that I have positively proved that XenServer hit this race
> during automatic testing. I agree that it shouldn't happen in reality
> for a system configured as expected, but that fact alone doesn't
> invalidate the fix itself.
I think it can happen even with upstream if two guests start at the same
time and both execute the code at the same time. Both will find the dir
does not exist yet and both will attempt to create the dir. I think one
of both will get an exception.
Olaf
next prev parent reply other threads:[~2014-10-29 19:43 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-29 14:09 [PATCH for-4.5] tools/pygrub: Fix TOCTOU race introduced by c/s 63dcc68 Andrew Cooper
2014-10-29 16:03 ` Olaf Hering
2014-10-29 18:09 ` Andrew Cooper
2014-10-29 19:43 ` Olaf Hering [this message]
2014-11-04 10:48 ` Ian Campbell
2014-11-04 10:52 ` Please *justify* your use of the for-4.5 tag when posting patches Ian Campbell
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