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From: Matthew Wilcox <willy@infradead.org>
To: Wan Jiabing <wanjiabing@vivo.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Vlastimil Babka <vbabka@suse.cz>,
	David Howells <dhowells@redhat.com>,
	linux-mm@kvack.org, linux-kernel@vger.kernel.org,
	Julia Lawall <Julia.Lawall@inria.fr>
Subject: Re: [PATCH] mm/filemap: Fix NULL pointer dereference in pagecache_get_page
Date: Tue, 26 Apr 2022 13:08:08 +0100	[thread overview]
Message-ID: <YmfgqKcMmstgfz+0@casper.infradead.org> (raw)
In-Reply-To: <20220426082549.590899-1-wanjiabing@vivo.com>

On Tue, Apr 26, 2022 at 04:25:48PM +0800, Wan Jiabing wrote:
> Fix following coccicheck error:
> mm/folio-compat.c:128:17-21: ERROR: folio is NULL but dereferenced.
>  	folio = __filemap_get_folio(mapping, index, fgp_flags, gfp);
> -	if ((fgp_flags & FGP_HEAD) || !folio || xa_is_value(folio))
> +	if (!folio)
> +		return NULL;
> +	if ((fgp_flags & FGP_HEAD) || xa_is_value(folio))
>  		return &folio->page;

That doesn't dereference the folio.  Coccicheck is wrong.


  reply	other threads:[~2022-04-26 12:08 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-04-26  8:25 [PATCH] mm/filemap: Fix NULL pointer dereference in pagecache_get_page Wan Jiabing
2022-04-26 12:08 ` Matthew Wilcox [this message]
2022-04-26 21:06   ` Andrew Morton
2022-04-26 21:17     ` Matthew Wilcox

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