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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 26C89CCA479 for ; Fri, 17 Jun 2022 16:28:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1383242AbiFQQ17 (ORCPT ); Fri, 17 Jun 2022 12:27:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40758 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229602AbiFQQ16 (ORCPT ); Fri, 17 Jun 2022 12:27:58 -0400 Received: from mail1.bemta35.messagelabs.com (mail1.bemta35.messagelabs.com [67.219.250.113]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E20321583F; Fri, 17 Jun 2022 09:27:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=motorola.com; s=Selector; t=1655483276; i=@motorola.com; bh=2kDYzt/VGbsG0nzURDxax2rcRa5S2Q9ZXehQBx7o2So=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:In-Reply-To; b=FyELOb68bKc/Wx57kMVFf2Pn1se1hE1RevDfi+7XKFNEf4htk16C6iEJjRbqbZjZn uM420vq/B/KUchC/iKdbUdUiFWdp+yPsi5bu/Bp6X9stCXyPD1uuNSkVrvNTOcYMVA T01iR8jSYDJF5mgbOQsNQiE7g5dxR9bgQdlFlQq9sx8C2CBFX7E1hveTZv3w9h63U8 4pjTnJPA709rQOXPNxnk+hb1TMtf3N+/xlsimeXoCWDEcdGgvD7TxjOEQiPJdcG9L+ jyYRThGk+7Od690ZGmkZzMqv1aQlXhUbfqz60/NslQsQjy9w44DDsmq2olXWXqtt+p ElnRVZ5KIIhDQ== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrGIsWRWlGSWpSXmKPExsUyYU+Ds2736jV JBjtfylkca3vCbtG8eD2bRefEJewWl3fNYbNYtKyV2WJL2xUmix9/+pgtFmx8xOjA4TG7Yyar x6ZVnWwe++euYffo/2vg8XmTXABrFGtmXlJ+RQJrxo65Z5gKJgtV7GroZ2lgvMTXxcjFISQwm Uli+ZqpzBDOQiaJRc1P2bsYOTlYBFQlHsyZwgJiswmoSSx4vYoZxBYRsJDoXTSdEcRmFmhhkj hzURjEFhbwlTg4fw9YnFdAWeLn+glsILaQQIbEm4YT7BBxQYmTM5+wQPRqSdz495Kpi5EDyJa WWP6PAyTMKWAlce35V6YJjLyzkHTMQtIxC6FjASPzKkbrpKLM9IyS3MTMHF1DAwNdQ0MTXUtL XUMTM73EKt1EvdJi3fLU4hJdI73E8mK91OJiveLK3OScFL281JJNjMAgTylKnrSD8XvfT71Dj JIcTEqivGVL1yQJ8SXlp1RmJBZnxBeV5qQWH2KU4eBQkuD9uwIoJ1iUmp5akZaZA4w4mLQEB4 +SCK/scqA0b3FBYm5xZjpE6hSjLkfn/q4DzEIsefl5qVLivLtXARUJgBRllObBjYBF/yVGWSl hXkYGBgYhnoLUotzMElT5V4ziHIxKwrznQS7hycwrgdv0CugIJqAjGvetADmiJBEhJdXAlNtj 9S3pZofHhKtnJ54usHJLmhgZYrZvwdXpTP1Xps/u3jqBSVB0Unb8bv77fccXKgmFbK9UuGFSu vN5iDfjvfCXUZ/uN+9eJcO6TCiOV7vg3s3WTWIZzHtKZBc36u5aEqXXuGfidcWSztu3DSb8WC +xYIdRvVDO1+0rHt7Re8b2I+yZ/P/ze3QYa2bEeBlPj53Ra57yZZlc9zLnPj+h1LtxUX68jvI 3BX2482frbXOzF3o5banZI/FnG1bMebM/163eO/rHGovs4MVPUmw7Gi1vWxSruyx2W1a/NWE7 f97PlO7ZzmcFV1dOqbz0zYB/p6bZyQdSbW2c+lNPBeRfiTC/0XnOI0AleV+MlXOpEktxRqKhF nNRcSIAqyBdWHkDAAA= X-Env-Sender: w36195@motorola.com X-Msg-Ref: server-13.tower-636.messagelabs.com!1655483274!23406!1 X-Originating-IP: [144.188.128.67] X-SYMC-ESS-Client-Auth: outbound-route-from=pass X-StarScan-Received: X-StarScan-Version: 9.86.7; banners=-,-,- X-VirusChecked: Checked Received: (qmail 18209 invoked from network); 17 Jun 2022 16:27:55 -0000 Received: from unknown (HELO ilclpfpp01.lenovo.com) (144.188.128.67) by server-13.tower-636.messagelabs.com with ECDHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 17 Jun 2022 16:27:55 -0000 Received: from ilclmmrp02.lenovo.com (ilclmmrp02.mot.com [100.65.83.26]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ilclpfpp01.lenovo.com (Postfix) with ESMTPS id 4LPkwp5DcFzfBZq; Fri, 17 Jun 2022 16:27:54 +0000 (UTC) Received: from p1g3 (unknown [10.45.6.83]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: w36195) by ilclmmrp02.lenovo.com (Postfix) with ESMTPSA id 4LPkwp3x5XzbrlP; Fri, 17 Jun 2022 16:27:54 +0000 (UTC) Date: Fri, 17 Jun 2022 11:27:35 -0500 From: Dan Vacura To: Laurent Pinchart Cc: linux-usb@vger.kernel.org, stable@vger.kernel.org, Felipe Balbi , Greg Kroah-Hartman , Paul Elder , Michael Grzeschik , linux-kernel@vger.kernel.org Subject: Re: [PATCH] usb: gadget: uvc: fix list double add in uvcg_video_pump Message-ID: References: <20220616030915.149238-1-w36195@motorola.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Hi Laurent, Thanks for the review! On Fri, Jun 17, 2022 at 03:51:08PM +0300, Laurent Pinchart wrote: > Hi Dan, > > Thank you for the patch. > > On Wed, Jun 15, 2022 at 10:09:15PM -0500, Dan Vacura wrote: > > A panic can occur if the endpoint becomes disabled and the > > uvcg_video_pump adds the request back to the req_free list after it has > > already been queued to the endpoint. The endpoint complete will add the > > request back to the req_free list. Invalidate the local request handle > > once it's been queued. > > Good catch ! > > > <6>[ 246.796704][T13726] configfs-gadget gadget: uvc: uvc_function_set_alt(1, 0) > > <3>[ 246.797078][ T26] list_add double add: new=ffffff878bee5c40, prev=ffffff878bee5c40, next=ffffff878b0f0a90. > > <6>[ 246.797213][ T26] ------------[ cut here ]------------ > > <2>[ 246.797224][ T26] kernel BUG at lib/list_debug.c:31! > > <6>[ 246.807073][ T26] Call trace: > > <6>[ 246.807180][ T26] uvcg_video_pump+0x364/0x38c > > <6>[ 246.807366][ T26] process_one_work+0x2a4/0x544 > > <6>[ 246.807394][ T26] worker_thread+0x350/0x784 > > <6>[ 246.807442][ T26] kthread+0x2ac/0x320 > > > > Fixes: f9897ec0f6d3 ("usb: gadget: uvc: only pump video data if necessary") > > Cc: stable@vger.kernel.org > > Signed-off-by: Dan Vacura > > --- > > drivers/usb/gadget/function/uvc_video.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/drivers/usb/gadget/function/uvc_video.c b/drivers/usb/gadget/function/uvc_video.c > > index 93f42c7f800d..59e2f51b53a5 100644 > > --- a/drivers/usb/gadget/function/uvc_video.c > > +++ b/drivers/usb/gadget/function/uvc_video.c > > @@ -427,6 +427,9 @@ static void uvcg_video_pump(struct work_struct *work) > > if (ret < 0) { > > uvcg_queue_cancel(queue, 0); > > break; > > + } else { > > + /* Endpoint now owns the request */ > > + req = NULL; > > } > > video->req_int_count++; > > I'd write it as > > if (ret < 0) { > uvcg_queue_cancel(queue, 0); > break; > } > > /* Endpoint now owns the request. */ > req = NULL; > video->req_int_count++; This is cleaner. I'll send a v2 with this suggestion. > > Apart from that, > > Reviewed-by: Laurent Pinchart > > > } > > -- > Regards, > > Laurent Pinchart