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	Mon, 23 Mar 2026 19:44:44 -0300
Message-ID: <63655684a778145167a549b4a6251ccf@manguebit.org>
From: Paulo Alcantara <pc@manguebit.org>
To: ChenXiaoSong <chenxiaosong@chenxiaosong.com>, David Howells
 <dhowells@redhat.com>, Matthew Wilcox <willy@infradead.org>, Christoph
 Hellwig <hch@infradead.org>, Jens Axboe <axboe@kernel.dk>, Leon Romanovsky
 <leon@kernel.org>, Steve French <smfrench@gmail.com>
Cc: Christian Brauner <christian@brauner.io>, netfs@lists.linux.dev,
 linux-afs@lists.infradead.org, linux-cifs@vger.kernel.org,
 linux-nfs@vger.kernel.org, ceph-devel@vger.kernel.org,
 v9fs@lists.linux.dev, linux-fsdevel@vger.kernel.org,
 linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH 17/17] netfs: Combine prepare and issue ops and grab
 the buffers on request
In-Reply-To: <2d8ce118-2f7a-4b7f-8786-4581b29cb74e@chenxiaosong.com>
References: <20260304140328.112636-1-dhowells@redhat.com>
 <20260304140328.112636-18-dhowells@redhat.com>
 <2d8ce118-2f7a-4b7f-8786-4581b29cb74e@chenxiaosong.com>
Date: Mon, 23 Mar 2026 19:44:44 -0300
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ChenXiaoSong <chenxiaosong@chenxiaosong.com> writes:

> --- a/fs/netfs/direct_write.c
> +++ b/fs/netfs/direct_write.c
> @@ -161,8 +161,8 @@ static int netfs_unbuffered_write(struct 
> netfs_io_request *wreq)
>                                          break;
>                                  }
>                                  netfs_put_subrequest(subreq, 
> netfs_sreq_trace_put_failed);
> -                               subreq = NULL;
>                                  ret = subreq->error;
> +                               subreq = NULL;
>                                  goto failed;

Thanks for the review.  The above is still broken as it wolud cause an
UAF on @subreq as we're putting it with netfs_put_subrequest() and then
dereferencing it afterwards.

Besides, we could also get rid of 'subreq = NULL' as it is currently a
no-op -- including in other places.

Let's wait for next patchset from Dave, though.