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 7CC1FC433EF for ; Fri, 18 Feb 2022 07:57:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232199AbiBRH6I (ORCPT ); Fri, 18 Feb 2022 02:58:08 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:45032 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229504AbiBRH6H (ORCPT ); Fri, 18 Feb 2022 02:58:07 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 74207151D09; Thu, 17 Feb 2022 23:57:50 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 0F49561028; Fri, 18 Feb 2022 07:57:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7A0C1C340E9; Fri, 18 Feb 2022 07:57:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1645171069; bh=1RjXsiu3Z6SS4o/E9a4X65asxgr+t4tHtpZNXouQhc8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=cPYS2jFabTvnkMbQC77iAOAB25vBb+nAZUhtDb3CuoffF3jriH6wQss6h9EX85pQt AdTNny719PLHXh49AeUyXcgBkHcU3Db+BT5cZeC4PkA7qyrV/xx/LO0UpM1TWIHLNz CMOETdfRnGlB5XnVlHZ8HL/JTXe6Ty4CG0gIJPj8= Date: Fri, 18 Feb 2022 08:57:45 +0100 From: Greg Kroah-Hartman To: Daehwan Jung Cc: Felipe Balbi , Muchun Song , Andrew Morton , Christian Brauner , Stephen Rothwell , linux-usb@vger.kernel.org, open list Subject: Re: usb: gadget: function: add spinlock for rndis response list Message-ID: References: <1645162195-54476-1-git-send-email-dh10.jung@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1645162195-54476-1-git-send-email-dh10.jung@samsung.com> Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Fri, Feb 18, 2022 at 02:29:55PM +0900, Daehwan Jung wrote: > There's no lock for rndis response list. It could cause list corruption > if two different list_add at the same time like below. > It's better to add in rndis_add_response / rndis_free_response > / rndis_get_next_response to prevent any race condition on response list. > > [ 361.894299] [1: irq/191-dwc3:16979] list_add corruption. > next->prev should be prev (ffffff80651764d0), > but was ffffff883dc36f80. (next=ffffff80651764d0). > > [ 361.904380] [1: irq/191-dwc3:16979] Call trace: > [ 361.904391] [1: irq/191-dwc3:16979] __list_add_valid+0x74/0x90 > [ 361.904401] [1: irq/191-dwc3:16979] rndis_msg_parser+0x168/0x8c0 > [ 361.904409] [1: irq/191-dwc3:16979] rndis_command_complete+0x24/0x84 > [ 361.904417] [1: irq/191-dwc3:16979] usb_gadget_giveback_request+0x20/0xe4 > [ 361.904426] [1: irq/191-dwc3:16979] dwc3_gadget_giveback+0x44/0x60 > [ 361.904434] [1: irq/191-dwc3:16979] dwc3_ep0_complete_data+0x1e8/0x3a0 > [ 361.904442] [1: irq/191-dwc3:16979] dwc3_ep0_interrupt+0x29c/0x3dc > [ 361.904450] [1: irq/191-dwc3:16979] dwc3_process_event_entry+0x78/0x6cc > [ 361.904457] [1: irq/191-dwc3:16979] dwc3_process_event_buf+0xa0/0x1ec > [ 361.904465] [1: irq/191-dwc3:16979] dwc3_thread_interrupt+0x34/0x5c > > Fixes: f6281af9d62e ("usb: gadget: rndis: use list_for_each_entry_safe") > Signed-off-by: Daehwan Jung > --- > drivers/usb/gadget/function/rndis.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/usb/gadget/function/rndis.c b/drivers/usb/gadget/function/rndis.c > index b7ccf1803656..b4d58324e2d2 100644 > --- a/drivers/usb/gadget/function/rndis.c > +++ b/drivers/usb/gadget/function/rndis.c > @@ -1011,16 +1011,21 @@ void rndis_add_hdr(struct sk_buff *skb) > } > EXPORT_SYMBOL_GPL(rndis_add_hdr); > > +/* add spinlock to prevent race condition for rndis response list */ > +static DEFINE_SPINLOCK(resp_lock); Shouldn't this be one lock per rndis_params structure, and not a global one for the whole driver? thanks, greg k-h