From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-sn1nam02on0128.outbound.protection.outlook.com ([104.47.36.128]:23328 "EHLO NAM02-SN1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932102AbeDIAYn (ORCPT ); Sun, 8 Apr 2018 20:24:43 -0400 From: Sasha Levin To: "stable@vger.kernel.org" , "linux-kernel@vger.kernel.org" CC: Yisheng Xie , Andi Kleen , Chris Salls , Christopher Lameter , David Rientjes , Ingo Molnar , Naoya Horiguchi , Tan Xiaojun , Andrew Morton , Linus Torvalds , Sasha Levin Subject: [PATCH AUTOSEL for 4.14 100/161] mm/mempolicy: add nodes_empty check in SYSC_migrate_pages Date: Mon, 9 Apr 2018 00:21:12 +0000 Message-ID: <20180409001936.162706-100-alexander.levin@microsoft.com> References: <20180409001936.162706-1-alexander.levin@microsoft.com> In-Reply-To: <20180409001936.162706-1-alexander.levin@microsoft.com> Content-Language: en-US Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org List-ID: From: Yisheng Xie [ Upstream commit 0486a38bcc4749808edbc848f1bcf232042770fc ] As in manpage of migrate_pages, the errno should be set to EINVAL when none of the node IDs specified by new_nodes are on-line and allowed by the process's current cpuset context, or none of the specified nodes contain memory. However, when test by following case: new_nodes =3D 0; old_nodes =3D 0xf; ret =3D migrate_pages(pid, old_nodes, new_nodes, MAX); The ret will be 0 and no errno is set. As the new_nodes is empty, we should expect EINVAL as documented. To fix the case like above, this patch check whether target nodes AND current task_nodes is empty, and then check whether AND node_states[N_MEMORY] is empty. Link: http://lkml.kernel.org/r/1510882624-44342-4-git-send-email-xieyisheng= 1@huawei.com Signed-off-by: Yisheng Xie Acked-by: Vlastimil Babka Cc: Andi Kleen Cc: Chris Salls Cc: Christopher Lameter Cc: David Rientjes Cc: Ingo Molnar Cc: Naoya Horiguchi Cc: Tan Xiaojun Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- mm/mempolicy.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 80b67805b51d..2d3077ce50cd 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -1440,10 +1440,14 @@ SYSCALL_DEFINE4(migrate_pages, pid_t, pid, unsigned= long, maxnode, goto out_put; } =20 - if (!nodes_subset(*new, node_states[N_MEMORY])) { - err =3D -EINVAL; + task_nodes =3D cpuset_mems_allowed(current); + nodes_and(*new, *new, task_nodes); + if (nodes_empty(*new)) + goto out_put; + + nodes_and(*new, *new, node_states[N_MEMORY]); + if (nodes_empty(*new)) goto out_put; - } =20 err =3D security_task_movememory(task); if (err) --=20 2.15.1