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From:   Austin Kim <austindh.kim@gmail.com>
Date:   Fri, 21 May 2021 15:55:23 +0900
Message-ID: <CADLLry5J5GqB_Rw7n0aKcWgYPJZDOQP89mvyWT-GnB8KAiQrBA@mail.gmail.com>
Subject: Re: [PATCH] kernfs: move return value check after kmalloc()
To:     Greg KH <gregkh@linuxfoundation.org>
Cc:     tj@kernel.org, neilb@suse.de, linux-kernel@vger.kernel.org,
        =?UTF-8?B?6rmA64+Z7ZiE?= <austin.kim@lge.com>
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2021=EB=85=84 5=EC=9B=94 21=EC=9D=BC (=EA=B8=88) =EC=98=A4=ED=9B=84 1:39, G=
reg KH <gregkh@linuxfoundation.org>=EB=8B=98=EC=9D=B4 =EC=9E=91=EC=84=B1:
>
> On Fri, May 21, 2021 at 03:55:25AM +0100, Austin Kim wrote:
> > With 414985ae23c0 ("sysfs, kernfs: move file core code to fs/kernfs/fil=
e.c"),
> > 'return -ENOMEM' is executed when kmalloc() returns NULL.
> >
> > Since 'commit 4ef67a8c95f3 ("sysfs/kernfs: make read requests on pre-al=
loc
> > files use the buffer.")', 'return -ENOMEM' statement is not properly lo=
cated.
> >
> > Fix it by moving 'return -ENOMEM' after return from kmalloc().
> >
> > Fixes: 4ef67a8c95f3 ("sysfs/kernfs: make read requests on pre-alloc fil=
es use the buffer.")
> > Signed-off-by: Austin Kim <austindh.kim@gmail.com>
[...]
>
> Like Neil said, I don't see the "bug" you are fixing here.  What is
> currently wrong with the existing code?

I just found something to improve a little, which has nothing to do with 'B=
ug'.
(of->prealloc_buf is allocated ahead of kernfs_file_read_iter().)

Should be cautious of adding 'Fixes' tag.

Thanks

>
> thanks,
>
> greg k-h