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=-8.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 9438CC433E1 for ; Thu, 13 Aug 2020 19:51:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 72AAC20829 for ; Thu, 13 Aug 2020 19:51:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="i916syol" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726533AbgHMTvo (ORCPT ); Thu, 13 Aug 2020 15:51:44 -0400 Received: from m43-7.mailgun.net ([69.72.43.7]:13069 "EHLO m43-7.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726312AbgHMTvn (ORCPT ); Thu, 13 Aug 2020 15:51:43 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1597348303; h=Content-Transfer-Encoding: Content-Type: In-Reply-To: MIME-Version: Date: Message-ID: From: References: Cc: To: Subject: Sender; bh=dDK8BdAhyMff+YBgjmOEx9G0LZqK11Et6I+uQh1z7Wc=; b=i916syolOI0CvTDEVYLUSZQTxIPcjuNI/b7qLIkfe4FcYwMkH5gnboZIbuuJzONcgg4uIf65 uy8N7VAn1iRmf/lKZxqblPO69cNLQxeR+844jqp6xFNTj1TwqH28yvedOQSUVBv7zbKBKZLw 2bMbBnx/lD+vZFIjivnrsT++8co= X-Mailgun-Sending-Ip: 69.72.43.7 X-Mailgun-Sid: WyI0MWYwYSIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n08.prod.us-west-2.postgun.com with SMTP id 5f3599c803528d4024cd761c (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Thu, 13 Aug 2020 19:51:36 GMT Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 293F6C433C6; Thu, 13 Aug 2020 19:51:36 +0000 (UTC) Received: from [192.168.1.3] (unknown [183.83.140.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: prsood) by smtp.codeaurora.org (Postfix) with ESMTPSA id EE6BCC433C9; Thu, 13 Aug 2020 19:51:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org EE6BCC433C9 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=none smtp.mailfrom=prsood@codeaurora.org Subject: Re: [PATCH] firmware_loader: fix memory leak for paged buffer To: Takashi Iwai Cc: mcgrof@kernel.org, gregkh@linuxfoundation.org, rafael@kernel.org, linux-kernel@vger.kernel.org References: <1597258819-14080-1-git-send-email-prsood@codeaurora.org> From: Prateek Sood Message-ID: <3f9dac61-1ba5-1a44-1d08-75666c9398bc@codeaurora.org> Date: Fri, 14 Aug 2020 01:21:31 +0530 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/13/2020 6:28 PM, Takashi Iwai wrote: > On Wed, 12 Aug 2020 21:00:19 +0200, > Prateek Sood wrote: >> vfree() is being called on paged buffer allocated >> using alloc_page() and mapped using vmap(). >> >> Freeing of pages in vfree() relies on nr_pages of >> struct vm_struct. vmap() does not update nr_pages. >> It can lead to memory leaks. >> >> Signed-off-by: Prateek Sood > Thanks for spotting this out! This is essentially a revert of the > commit ddaf29fd9bb6 ("firmware: Free temporary page table after > vmapping"), so better to mention it via Fixes tag as well as Cc to > stable. > About the changes: >> --- a/drivers/base/firmware_loader/firmware.h >> +++ b/drivers/base/firmware_loader/firmware.h >> @@ -142,10 +142,12 @@ static inline void fw_state_done(struct fw_priv *fw_priv) >> void fw_free_paged_buf(struct fw_priv *fw_priv); >> int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed); >> int fw_map_paged_buf(struct fw_priv *fw_priv); >> +bool fw_is_paged_buf(struct fw_priv *fw_priv); > I guess this isn't necessary if we just swap the call order of > fw_free_paged_buf() and vfree(); then fw_priv->is_paged_buf is > referred only in fw_free_paged_buf(). > That is, something like below. > > In anyway, take my review tag: > Reviewed-by: Takashi Iwai Thanks for reviewing. I would prefer to keep the patch as is to have vmap() and vunmap() pair used for readability. Will upload a new version with Fixes tag and your Reviewed-by. > > thanks, > > Takashi > > --- a/drivers/base/firmware_loader/main.c > +++ b/drivers/base/firmware_loader/main.c > @@ -252,9 +252,9 @@ static void __free_fw_priv(struct kref *ref) > list_del(&fw_priv->list); > spin_unlock(&fwc->lock); > > - fw_free_paged_buf(fw_priv); /* free leftover pages */ > if (!fw_priv->allocated_size) > vfree(fw_priv->data); > + fw_free_paged_buf(fw_priv); /* free leftover pages */ > kfree_const(fw_priv->fw_name); > kfree(fw_priv); > } > @@ -272,7 +272,7 @@ void fw_free_paged_buf(struct fw_priv *fw_priv) > { > int i; > > - if (!fw_priv->pages) > + if (!fw_priv->is_paged_buf) > return; > > for (i = 0; i < fw_priv->nr_pages; i++) > @@ -328,10 +328,6 @@ int fw_map_paged_buf(struct fw_priv *fw_priv) > if (!fw_priv->data) > return -ENOMEM; > > - /* page table is no longer needed after mapping, let's free */ > - kvfree(fw_priv->pages); > - fw_priv->pages = NULL; > - > return 0; > } > #endif -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc., is a member of Code Aurora Forum, a Linux Foundation Collaborative Project