From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sender-of-o55.zoho.eu (sender-of-o55.zoho.eu [136.143.169.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 998D924336D for ; Wed, 25 Mar 2026 07:31:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.169.55 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774423870; cv=pass; b=Vf6EyHN9Rd1+NpLSR6/BqKketFHaBZJNZOuANVoSpzI6LR+gvz84dnUgl1igA/SnBl0ORtNjmie8GDXSMN0c9vfdP0BFhOtM7CjVzYMqK1eYlUj9RUSJGXHraQ8e9ZI8BXQ/A7Sh4nN/xtRz94K68igbE12OA2C5GA5IBxaIjdY= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774423870; c=relaxed/simple; bh=+4d/k+m5w22u/YvF8HJ7/reHAIlY0ui2S1zdu+6S13Q=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=DtZBQr97Sh/MFkD36UMiKN+lUCBjoAOdX8fHszrloFas+kJLCuzDC9xyl95tzszGpwFU+QHZdEVBs8n5hxE+W7lt/ukvpaHd1ozBVtBc27WCn3eNLWQNmVPEZIhyLGo1yIDwTK4SldxBkr/zpYdZ+DUeb3dGC/Z2/w9A6MP78Lc= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=objecting.org; spf=pass smtp.mailfrom=objecting.org; dkim=pass (1024-bit key) header.d=objecting.org header.i=objecting@objecting.org header.b=VBlvPRQO; arc=pass smtp.client-ip=136.143.169.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=objecting.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=objecting.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=objecting.org header.i=objecting@objecting.org header.b="VBlvPRQO" ARC-Seal: i=1; a=rsa-sha256; t=1774423839; cv=none; d=zohomail.eu; s=zohoarc; b=RgkZUvzrFXb7IUuxWpYRPPG4sVRS1HxPT41WVuBSgXH8BBsrDEZsPZIYNIWsZXXdmd/IUp/mqpwT8JNX9xim5rnrc4TfikF8qMaVm+60NUg/7JiQdKO6gxUtKnP190dTNmMOTNo7ezzrbsdX5hVC0QXXNIRh+wWN3Jg992GQUxc= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.eu; s=zohoarc; t=1774423839; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:MIME-Version:Message-ID:Subject:Subject:To:To:Message-Id:Reply-To; bh=LRor7oZnl2gk48SOhwpp5bgA4g98rV8TzWVj64hfSy4=; b=b5qmkAZgf+j2gwuvQCZEFmWTJ0XKTiMGv1hqHVwuwudKLvcqRks+GVuj9eCGQFEwBFBGGKolnWJ3KEgT20JXdghxccGdKNNd9kc2Se+kgwSAfmFa5iVYAGcW9Sr9rOtM6n4ZdqsN21B5OjL6bkaR6Q3UiYvzfJCRJ1C6LlFBJh0= ARC-Authentication-Results: i=1; mx.zohomail.eu; dkim=pass header.i=objecting.org; spf=pass smtp.mailfrom=objecting@objecting.org; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1774423839; s=zmail; d=objecting.org; i=objecting@objecting.org; h=From:From:To:To:Cc:Cc:Subject:Subject:Date:Date:Message-Id:Message-Id:MIME-Version:Content-Transfer-Encoding:Reply-To; bh=LRor7oZnl2gk48SOhwpp5bgA4g98rV8TzWVj64hfSy4=; b=VBlvPRQOpyfhT5XN0xWlL9ZblM7oGQNSVZXaTMYjjhCjiqRZ7yqp8mvyVyBt1qKN Hhsv7DIsq1t4Uv02iQXdmkZJWfiB1zHszFy2DPgF2L0kh/sXvReVus7wboW0ak+ySYR uGWNJzwjcwjw/BG1GdAmiQ8QLwWLew+81csNbMRQ= Received: by mx.zoho.eu with SMTPS id 1774423836046413.8985698344709; Wed, 25 Mar 2026 08:30:36 +0100 (CET) From: Josh Law To: SeongJae Park , Andrew Morton Cc: damon@lists.linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Josh Law Subject: [PATCH] mm/damon/core: validate goal nid before accessing node data Date: Wed, 25 Mar 2026 07:30:34 +0000 Message-Id: <20260325073034.140353-1-objecting@objecting.org> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-ZohoMailClient: External damos_get_node_mem_bp() and damos_get_node_memcg_used_bp() pass goal->nid directly to si_meminfo_node() and NODE_DATA() without checking that it refers to a valid, online NUMA node. Since goal->nid is set from userspace via sysfs with no validation, a negative or out-of-range value causes an out-of-bounds access in NODE_DATA(), and a valid but offline node gives undefined results. Add bounds and node_online() checks before using the nid. Fixes: 0e1c773b501f ("mm/damon/core: introduce damos quota goal metrics for memory node utilization") Signed-off-by: Josh Law --- mm/damon/core.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/mm/damon/core.c b/mm/damon/core.c index 59b709f04975..6ee421141996 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -2227,6 +2227,10 @@ static __kernel_ulong_t damos_get_node_mem_bp( struct sysinfo i; __kernel_ulong_t numerator; + if (goal->nid < 0 || goal->nid >= MAX_NUMNODES || + !node_online(goal->nid)) + return 0; + si_meminfo_node(&i, goal->nid); if (goal->metric == DAMOS_QUOTA_NODE_MEM_USED_BP) numerator = i.totalram - i.freeram; @@ -2243,6 +2247,10 @@ static unsigned long damos_get_node_memcg_used_bp( unsigned long used_pages, numerator; struct sysinfo i; + if (goal->nid < 0 || goal->nid >= MAX_NUMNODES || + !node_online(goal->nid)) + return 0; + memcg = mem_cgroup_get_from_id(goal->memcg_id); if (!memcg) { if (goal->metric == DAMOS_QUOTA_NODE_MEMCG_USED_BP) -- 2.34.1