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=-8.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,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 60A21C04EB8 for ; Fri, 30 Nov 2018 10:08:00 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3162220863 for ; Fri, 30 Nov 2018 10:08:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="pEhXSP7Q" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3162220863 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=be4energy.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=MeIVNPCJocGLAFdmn2GnCTMB8JCDaCYBiaG2cOOoDSY=; b=pEhXSP7QHCrPJl u0PRaxWW0U+dk6gWTd9OWjKZpjkvjEZtC7Wxj2FdmOeE7xO5gkLLOfN8UVG2BJhkFMjr8WYUB3cQn zoaOr3o2qMnoBpZXYh6l8ROcs37NCHyjICQvr0E3KU7/w4pibwj75NeBS80JTixxHWWaLNns2bEyf 8NIa7e5JV9Tk6NvDICZ8SlIepSbDu36NFeIru+LGKbEULA34w9Jp67Nyj7h78A40r3cVRUm1t1HVY 4w/1uC6NA4INlX/Kwc+MTu4QSoQXlwoleMYVmDgn2mhUlF7jPHQovI/yBbUBzqqKpAGeEhDc3Xkhk J+pgw7G9uzNN468++WIQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gSfiG-0003by-2z; Fri, 30 Nov 2018 10:07:56 +0000 Received: from mail.be4energy.com ([217.6.180.170]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gSfiD-0003ar-5A for linux-arm-kernel@lists.infradead.org; Fri, 30 Nov 2018 10:07:54 +0000 Received: from linux-7rm0.localnet (172.16.135.185) by SVRDC01.be4energy.local (172.16.135.100) with Microsoft SMTP Server id 14.3.361.1; Fri, 30 Nov 2018 11:07:40 +0100 From: Mario Forner To: Richard Genoud Subject: Re: [PATCH] dmaengine: at_hdmac: fix memory leak in at_dma_xlate() Date: Fri, 30 Nov 2018 11:07:39 +0100 Message-ID: <3059696.Xnxl6OxYbg@linux-7rm0> Organization: be4energy GmbH In-Reply-To: <20181127160635.11836-1-richard.genoud@gmail.com> References: <20181127160635.11836-1-richard.genoud@gmail.com> MIME-Version: 1.0 X-Originating-IP: [172.16.135.185] X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181130_020753_199955_525D0F57 X-CRM114-Status: GOOD ( 15.93 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Alexandre Belloni , Maxime Ripard , linux-kernel@vger.kernel.org, Ludovic Desroches , stable@vger.kernel.org, Vinod Koul , linux-serial@vger.kernel.org, dmaengine@vger.kernel.org, Dan Williams , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Am Dienstag, 27. November 2018, 17:06:34 CET schrieb Richard Genoud: > The leak was found when opening/closing a serial port a great number of > time, increasing kmalloc-32 in slabinfo. > > Each time the port was opened, dma_request_slave_channel() was called. > Then, in at_dma_xlate(), atslave was allocated with devm_kzalloc() and > never freed. (Well, it was free at module unload, but that's not what we > want). > So, here, kzalloc is more suited for the job since it has to be freed in > atc_free_chan_resources(). > > Cc: stable@vger.kernel.org > Fixes: bbe89c8e3d59 ("at_hdmac: move to generic DMA binding") > Reported-by: Mario Forner > Suggested-by: Alexandre Belloni > Acked-by: Alexandre Belloni > Signed-off-by: Richard Genoud After testing I installed an updated kernel on a production machine, which worked fine. The memory leak has been repaired successfully. There have been no adverse side-effects. Thank you for providing the patch. > --- > drivers/dma/at_hdmac.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c > index 7cbac6e8c113..1b7f0ca0d5cd 100644 > --- a/drivers/dma/at_hdmac.c > +++ b/drivers/dma/at_hdmac.c > @@ -1641,6 +1641,12 @@ static void atc_free_chan_resources(struct dma_chan *chan) > atchan->descs_allocated = 0; > atchan->status = 0; > > + /* > + * Free atslave allocated in at_dma_xlate() > + */ > + kfree(chan->private); > + chan->private = NULL; > + > dev_vdbg(chan2dev(chan), "free_chan_resources: done\n"); > } > > @@ -1675,7 +1681,7 @@ static struct dma_chan *at_dma_xlate(struct of_phandle_args *dma_spec, > dma_cap_zero(mask); > dma_cap_set(DMA_SLAVE, mask); > > - atslave = devm_kzalloc(&dmac_pdev->dev, sizeof(*atslave), GFP_KERNEL); > + atslave = kzalloc(sizeof(*atslave), GFP_KERNEL); > if (!atslave) > return NULL; > > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel