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Date: Tue, 9 Feb 2016 23:13:28 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Mike Marshall <hubcap@omnibond.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>,
	Stephen Rothwell <sfr@canb.auug.org.au>
Subject: Re: Orangefs ABI documentation
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On Tue, Feb 09, 2016 at 10:40:50PM +0000, Al Viro wrote:

> And the version in orangefs-2.9.3.tar.gz (your Frankenstein module?) is
> vulnerable to the same race.  2.8.1 isn't - it ignores signals on the
> cancel, but that means waiting for cancel to be processed (or timed out)
> on any interrupted read() before we return to userland.  We can return
> to that behaviour, of course, but I suspect that offloading it to something
> async (along with freeing the slot used by original operation) would be
> better from QoI point of view.

That breakage had been introduced between 2.8.5 and 2.8.6 (at some point
during the spring of 2012).  AFAICS, all versions starting with 2.8.6 are
vulnerable...