linux-kernel - [RFC PATCH 1/2] include/linux/gfp.h: Do not allocate pages on a offlined node

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: <20211206033338.743270-2-npache@redhat.com>
Date:   Sun,  5 Dec 2021 22:33:37 -0500
From:   Nico Pache <npache@...hat.com>
To:     linux-kernel@...r.kernel.org, linux-mm@...ck.org,
        akpm@...ux-foundation.org
Cc:     shakeelb@...gle.com, ktkhai@...tuozzo.com, shy828301@...il.com,
        guro@...com, vbabka@...e.cz, vdavydov.dev@...il.com,
        raquini@...hat.com, Rafael Aquini <aquini@...hat.com>
Subject: [RFC PATCH 1/2] include/linux/gfp.h: Do not allocate pages on a offlined node

We shouldn't allocate pages on a unavailable node. Add a check for this
in __alloc_pages_node and return NULL to avoid issues further down the
callchain.

Also update the VM_WARN_ON in __alloc_pages_node which could skip this
warn if the gfp_mask is not GFP_THISNODE.

Co-developed-by: Rafael Aquini <aquini@...hat.com>
Signed-off-by: Nico Pache <npache@...hat.com>
---
 include/linux/gfp.h | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index b976c4177299..e7e18f6d0d9d 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -565,7 +565,10 @@ static inline struct page *
 __alloc_pages_node(int nid, gfp_t gfp_mask, unsigned int order)
 {
 	VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES);
-	VM_WARN_ON((gfp_mask & __GFP_THISNODE) && !node_online(nid));
+	VM_WARN_ON(!node_online(nid));
+
+	if (!node_online(nid))
+		return NULL;
 
 	return __alloc_pages(gfp_mask, order, nid, NULL);
 }
-- 
2.33.1