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Date:   Fri, 7 May 2021 11:26:34 +0100
From:   Mel Gorman <mgorman@techsingularity.net>
To:     Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Alexander Lobakin <alobakin@pm.me>,
        Vlastimil Babka <vbabka@suse.cz>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/page_alloc: __alloc_pages_bulk(): do bounds check
 before accessing array
Message-ID: <20210507102634.GD9524@techsingularity.net>
References: <20210507064504.1712559-1-linux@rasmusvillemoes.dk>
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On Fri, May 07, 2021 at 08:45:03AM +0200, Rasmus Villemoes wrote:
> In the event that somebody would call this with an already fully
> populated page_array, the last loop iteration would do an access
> beyond the end of page_array.
> 
> It's of course extremely unlikely that would ever be done, but this
> triggers my internal static analyzer. Also, if it really is not
> supposed to be invoked this way (i.e., with no NULL entries in
> page_array), the nr_populated<nr_pages check could simply be removed
> instead.
> 
> Fixes: 0f87d9d30f21 (mm/page_alloc: add an array-based interface to the bulk page allocator)
> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>

Acked-by: Mel Gorman <mgorman@techsingularity.net>

-- 
Mel Gorman
SUSE Labs