linux-kernel - [PATCH 14/16] mm/migration: fix potential invalid node access for reclaim-based migration

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20220304093409.25829-15-linmiaohe@huawei.com>
Date:   Fri, 4 Mar 2022 17:34:07 +0800
From:   Miaohe Lin <linmiaohe@...wei.com>
To:     <akpm@...ux-foundation.org>
CC:     <mike.kravetz@...cle.com>, <shy828301@...il.com>,
        <willy@...radead.org>, <ying.huang@...el.com>, <ziy@...dia.com>,
        <minchan@...nel.org>, <apopple@...dia.com>,
        <ave.hansen@...ux.intel.com>, <o451686892@...il.com>,
        <almasrymina@...gle.com>, <jhubbard@...dia.com>,
        <rcampbell@...dia.com>, <peterx@...hat.com>,
        <naoya.horiguchi@....com>, <mhocko@...e.com>, <riel@...hat.com>,
        <linux-mm@...ck.org>, <linux-kernel@...r.kernel.org>,
        <linmiaohe@...wei.com>
Subject: [PATCH 14/16] mm/migration: fix potential invalid node access for reclaim-based migration

If we failed to setup hotplug state callbacks for mm/demotion:online in
some corner cases, node_demotion will be left uninitialized. Invalid node
might be returned from the next_demotion_node() when doing reclaim-based
migration. Use kcalloc to allocate node_demotion to fix the issue.

Fixes: ac16ec835314 ("mm: migrate: support multiple target nodes demotion")
Signed-off-by: Miaohe Lin <linmiaohe@...wei.com>
---
 mm/migrate.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/mm/migrate.c b/mm/migrate.c
index 279940c0c064..7b1c0b988234 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -2516,9 +2516,9 @@ static int __init migrate_on_reclaim_init(void)
 {
 	int ret;
 
-	node_demotion = kmalloc_array(nr_node_ids,
-				      sizeof(struct demotion_nodes),
-				      GFP_KERNEL);
+	node_demotion = kcalloc(nr_node_ids,
+				sizeof(struct demotion_nodes),
+				GFP_KERNEL);
 	WARN_ON(!node_demotion);
 
 	ret = cpuhp_setup_state_nocalls(CPUHP_MM_DEMOTION_DEAD, "mm/demotion:offline",
-- 
2.23.0