From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [PATCH] fs: check f_op before dereference its field
Date: Thu, 24 Jan 2013 15:28:39 +0000
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Cc: linux-fsdevel@vger.kernel.org
To: Jiang Fang <jiang.xx.fang@gmail.com>
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On Thu, Jan 24, 2013 at 10:53:20PM +0800, Jiang Fang wrote:
> I don't know whether we can have NULL f_op today, but a quick
> grep of '!file->f_op->' in fs directory shows most of times we
> do the check. So fix the missing one.

We should remove the bogus ones, actually, and hunt down the remaining
few places that set ->f_op to NULL (AFAICS, all of them in dvb and
in ->release() instances, at that; note that no methods can be ever
called after ->release(), so these assignments are pointless _and_
irrelevant for any call sites of the methods).