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From:   Miaohe Lin <linmiaohe@huawei.com>
To:     <akpm@linux-foundation.org>
CC:     <david@redhat.com>, <osalvador@suse.de>, <linux-mm@kvack.org>,
        <linux-kernel@vger.kernel.org>, <linmiaohe@huawei.com>
Subject: [PATCH 13/16] mm/page_alloc: init local variable buddy_pfn
Date:   Fri, 9 Sep 2022 17:24:48 +0800
Message-ID: <20220909092451.24883-14-linmiaohe@huawei.com>
In-Reply-To: <20220909092451.24883-1-linmiaohe@huawei.com>
References: <20220909092451.24883-1-linmiaohe@huawei.com>
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The local variable buddy_pfn could be passed to buddy_merge_likely()
without initialization if the passed in order is MAX_ORDER - 1. This
looks buggy but buddy_pfn won't be used in this case as there's a
order >= MAX_ORDER - 2 check. Init buddy_pfn to 0 anyway to avoid
possible future misuse.

Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
---
 mm/page_alloc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index e1c7f98cff96..63ad25e86010 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1113,7 +1113,7 @@ static inline void __free_one_page(struct page *page,
 		int migratetype, fpi_t fpi_flags)
 {
 	struct capture_control *capc = task_capc(zone);
-	unsigned long buddy_pfn;
+	unsigned long buddy_pfn = 0;
 	unsigned long combined_pfn;
 	struct page *buddy;
 	bool to_tail;
-- 
2.23.0