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Date:   Mon, 15 Jun 2020 15:48:04 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Christoph Hellwig <hch@lst.de>, Al Viro <viro@zeniv.linux.org.uk>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Ian Kent <raven@themaw.net>,
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        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
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Subject: Re: [PATCH 05/13] fs: check FMODE_WRITE in __kernel_write
Message-ID: <20200615134804.GA11061@lst.de>
References: <20200615121257.798894-1-hch@lst.de> <20200615121257.798894-6-hch@lst.de> <20200615123439.GT8681@bombadil.infradead.org>
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On Mon, Jun 15, 2020 at 05:34:39AM -0700, Matthew Wilcox wrote:
> On Mon, Jun 15, 2020 at 02:12:49PM +0200, Christoph Hellwig wrote:
> > We still need to check if the fѕ is open write, even for the low-level
> > helper.
> 
> Do we need the analogous check for FMODE_READ in the __kernel_read()
> patch?

Yes, we should probably grow it.  Hoping that none of the caller
actually wants to mess with files not open for reading as some of them
are rather dodgy.