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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 D6C1BC433E6 for ; Mon, 11 Jan 2021 12:01:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8E27C224BD for ; Mon, 11 Jan 2021 12:01:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729913AbhAKMBP (ORCPT ); Mon, 11 Jan 2021 07:01:15 -0500 Received: from mx2.suse.de ([195.135.220.15]:49112 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726807AbhAKMBP (ORCPT ); Mon, 11 Jan 2021 07:01:15 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 54F1FABC4; Mon, 11 Jan 2021 12:00:33 +0000 (UTC) Message-ID: <7d6dc09fedc84f9fce942d85c34d5cd41931bbf6.camel@suse.de> Subject: Re: [PATCH v2] can: mcba_usb: Fix memory leak when cancelling urb From: Oliver Neukum To: Bui Quang Minh , linux-usb@vger.kernel.org Cc: a.darwish@linutronix.de, bigeasy@linutronix.de, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, stern@rowland.harvard.edu, syzkaller-bugs@googlegroups.com, tglx@linutronix.de Date: Mon, 11 Jan 2021 13:00:31 +0100 In-Reply-To: <20210111104927.2561-1-minhquangbui99@gmail.com> References: <20210111104927.2561-1-minhquangbui99@gmail.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.34.4 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Montag, den 11.01.2021, 10:49 +0000 schrieb Bui Quang Minh: > In mcba_usb_read_bulk_callback(), when we don't resubmit or fails to > resubmit the urb, we need to deallocate the transfer buffer that is > allocated in mcba_usb_start(). > > Reported-by: syzbot+57281c762a3922e14dfe@syzkaller.appspotmail.com > Signed-off-by: Bui Quang Minh > --- > v1: add memory leak fix when not resubmitting urb > v2: add memory leak fix when failing to resubmit urb > > drivers/net/can/usb/mcba_usb.c | 11 ++++++++--- > 1 file changed, 8 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/can/usb/mcba_usb.c b/drivers/net/can/usb/mcba_usb.c > index df54eb7d4b36..30236e640116 100644 > --- a/drivers/net/can/usb/mcba_usb.c > +++ b/drivers/net/can/usb/mcba_usb.c > @@ -584,6 +584,8 @@ static void mcba_usb_read_bulk_callback(struct urb *urb) > case -EPIPE: > case -EPROTO: > case -ESHUTDOWN: > + usb_free_coherent(urb->dev, urb->transfer_buffer_length, > + urb->transfer_buffer, urb->transfer_dma); > return; > Can you call usb_free_coherent() in what can be hard IRQ context? Regards Oliver