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Date: Mon, 9 Oct 2017 17:22:22 +0100
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Jan Kara <jack@suse.cz>, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, cluster-devel@redhat.com
Subject: Re: [PATCH] direct-io: Prevent NULL pointer access in
 submit_page_section
Message-ID: <20171009162222.GW21978@ZenIV.linux.org.uk>
References: <20171009091318.26714-1-agruenba@redhat.com>
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On Mon, Oct 09, 2017 at 11:13:18AM +0200, Andreas Gruenbacher wrote:
> In the code added to function submit_page_section by commit b1058b981,
> sdio->bio can currently be NULL when calling dio_bio_submit.  This then
> leads to a NULL pointer access in dio_bio_submit, so check for a NULL
> bio in submit_page_section before trying to submit it instead.
> 
> Fixes xfstest generic/250 on gfs2.
> 
> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
> Reviewed-by: Jan Kara <jack@suse.cz>

How far back in -stable should it go?  I'm fine with the patch, but I'd
rather have accurate Cc: stable in commit message...