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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 2B83CC43387 for ; Tue, 1 Jan 2019 08:53:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F01B92080D for ; Tue, 1 Jan 2019 08:53:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728504AbfAAIv4 (ORCPT ); Tue, 1 Jan 2019 03:51:56 -0500 Received: from mx2.suse.de ([195.135.220.15]:36940 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727302AbfAAIv4 (ORCPT ); Tue, 1 Jan 2019 03:51:56 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 6F88FAE86; Tue, 1 Jan 2019 08:51:54 +0000 (UTC) Date: Tue, 01 Jan 2019 09:51:53 +0100 Message-ID: From: Takashi Iwai To: " huang.zijiang " Cc: , , , , , , , Subject: Re: [PATCH] sound:emu10k1:Use kmemdup instead of duplicating its function In-Reply-To: <1545640968-42357-1-git-send-email-huang.zijiang@zte.com.cn> References: <1545640968-42357-1-git-send-email-huang.zijiang@zte.com.cn> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/26 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 24 Dec 2018 09:42:48 +0100, huang.zijiang wrote: > > From: "huang.zijiang" > > kmemdup has implemented the function that kmalloc() and memcpy(). > > Signed-off-by: huang.zijiang > --- > sound/pci/emu10k1/emufx.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/sound/pci/emu10k1/emufx.c b/sound/pci/emu10k1/emufx.c > index 6ebe817..b4fe4c5 100644 > --- a/sound/pci/emu10k1/emufx.c > +++ b/sound/pci/emu10k1/emufx.c > @@ -671,10 +671,9 @@ static unsigned int *copy_tlv(const unsigned int __user *_tlv, bool in_kernel) > return NULL; > if (data[1] >= MAX_TLV_SIZE) > return NULL; > - tlv = kmalloc(data[1] + sizeof(data), GFP_KERNEL); > + tlv = kmemdup(data, data[1] + sizeof(data), GFP_KERNEL); > if (!tlv) > return NULL; > - memcpy(tlv, data, sizeof(data)); These changes are not equivalent, and rather dangerous, unfortunately. The memcpy() performs only for sizeof(data), and in this case, it's not the same size as the allocation above. thanks, Takashi