From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9EBD0C433E0 for ; Wed, 3 Jun 2020 08:42:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 84D85206C3 for ; Wed, 3 Jun 2020 08:42:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726354AbgFCImM (ORCPT ); Wed, 3 Jun 2020 04:42:12 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:5847 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726150AbgFCImL (ORCPT ); Wed, 3 Jun 2020 04:42:11 -0400 Received: from DGGEMS408-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 11FBF637D0B8783E79BB; Wed, 3 Jun 2020 16:42:09 +0800 (CST) Received: from SWX921481.china.huawei.com (10.126.202.66) by DGGEMS408-HUB.china.huawei.com (10.3.19.208) with Microsoft SMTP Server id 14.3.487.0; Wed, 3 Jun 2020 16:41:58 +0800 From: Barry Song To: , CC: , , , , Barry Song Subject: [PATCH 1/2] mm: cma: fix the name of CMA areas Date: Wed, 3 Jun 2020 20:40:24 +1200 Message-ID: <20200603084025.62740-2-song.bao.hua@hisilicon.com> X-Mailer: git-send-email 2.21.0.windows.1 In-Reply-To: <20200603084025.62740-1-song.bao.hua@hisilicon.com> References: <20200603084025.62740-1-song.bao.hua@hisilicon.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.126.202.66] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org if users give a name saved in stack, the current code will generate magic pointer. if users don't give a name(NULL), kasprintf() will always return NULL as we are at the early stage. that means cma_init_reserved_mem() will return -ENOMEM if users set name parameter as NULL. Cc: Roman Gushchin Signed-off-by: Barry Song --- mm/cma.c | 13 ++++++------- mm/cma.h | 4 +++- 2 files changed, 9 insertions(+), 8 deletions(-) diff --git a/mm/cma.c b/mm/cma.c index 0463ad2ce06b..b24151fa2101 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -202,13 +202,12 @@ int __init cma_init_reserved_mem(phys_addr_t base, phys_addr_t size, * subsystems (like slab allocator) are available. */ cma = &cma_areas[cma_area_count]; - if (name) { - cma->name = name; - } else { - cma->name = kasprintf(GFP_KERNEL, "cma%d\n", cma_area_count); - if (!cma->name) - return -ENOMEM; - } + + if (name) + snprintf(cma->name, CMA_MAX_NAME, name); + else + snprintf(cma->name, CMA_MAX_NAME, "cma%d\n", cma_area_count); + cma->base_pfn = PFN_DOWN(base); cma->count = size >> PAGE_SHIFT; cma->order_per_bit = order_per_bit; diff --git a/mm/cma.h b/mm/cma.h index 33c0b517733c..27d3f0e9f68f 100644 --- a/mm/cma.h +++ b/mm/cma.h @@ -2,6 +2,8 @@ #ifndef __MM_CMA_H__ #define __MM_CMA_H__ +#define CMA_MAX_NAME 64 + struct cma { unsigned long base_pfn; unsigned long count; @@ -12,7 +14,7 @@ struct cma { struct hlist_head mem_head; spinlock_t mem_head_lock; #endif - const char *name; + char name[CMA_MAX_NAME]; }; extern struct cma cma_areas[MAX_CMA_AREAS]; -- 2.23.0