From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751821AbdJZHgV (ORCPT ); Thu, 26 Oct 2017 03:36:21 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47552 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750919AbdJZHgS (ORCPT ); Thu, 26 Oct 2017 03:36:18 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 903CC81E09 Authentication-Results: ext-mx01.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx01.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=liwang@redhat.com From: Li Wang To: linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org Cc: schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, mingo@kernel.org, hughd@google.com, paul.gortmaker@windriver.com, mhocko@suse.com, shuwang@redhat.com, liwang@redhat.com Subject: [PATCH] s390/mm: return -ENOMEM in arch_get_unmapped_area[_topdown] Date: Thu, 26 Oct 2017 15:36:10 +0800 Message-Id: <20171026073610.9139-1-liwang@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Thu, 26 Oct 2017 07:36:18 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org That would be very hard to get -ENOMEM returned in crst_table_upgrade() because the condition(addr + len <= TASK_SIZE) makes all 'end' value is smaller/equal than 'TASK_SIZE_TASK'. So let's move it to the upper layer. Fixes: 8ab867cb0806 (s390/mm: fix BUG_ON in crst_table_upgrade) Signed-off-by: Li Wang --- arch/s390/mm/mmap.c | 6 ++++++ arch/s390/mm/pgalloc.c | 3 +-- 2 files changed, 7 insertions(+), 2 deletions(-) diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c index 5bea139..8ddb13a 100644 --- a/arch/s390/mm/mmap.c +++ b/arch/s390/mm/mmap.c @@ -119,6 +119,9 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, return addr; check_asce_limit: + if (addr + len >= TASK_SIZE_MAX) + return -ENOMEM; + if (addr + len > current->mm->context.asce_limit && addr + len <= TASK_SIZE) { rc = crst_table_upgrade(mm, addr + len); @@ -184,6 +187,9 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, } check_asce_limit: + if (addr + len >= TASK_SIZE_MAX) + return -ENOMEM; + if (addr + len > current->mm->context.asce_limit && addr + len <= TASK_SIZE) { rc = crst_table_upgrade(mm, addr + len); diff --git a/arch/s390/mm/pgalloc.c b/arch/s390/mm/pgalloc.c index 05f1f27..5e4b887 100644 --- a/arch/s390/mm/pgalloc.c +++ b/arch/s390/mm/pgalloc.c @@ -84,8 +84,7 @@ int crst_table_upgrade(struct mm_struct *mm, unsigned long end) /* upgrade should only happen from 3 to 4, 3 to 5, or 4 to 5 levels */ VM_BUG_ON(mm->context.asce_limit < _REGION2_SIZE); - if (end >= TASK_SIZE_MAX) - return -ENOMEM; + rc = 0; notify = 0; while (mm->context.asce_limit < end) { -- 2.9.3