From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4D71515C8 for ; Sun, 17 Sep 2023 08:04:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 70B4AC433C7; Sun, 17 Sep 2023 08:04:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1694937887; bh=1h5LcJ03IUO48wVxTPxjCPe7OlWV58gb87QmcYg6uuQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=LubuApJ/ahdQUlJAbFGW/avEpTKbuPb8jGK4Wmih51twXHgNZZk1kPJrrv6amXOlH 3vDGAz1HYb2NwvCM6Z7H1vthBFQ625vewD2Zz9PUWde4UWw1/RmyK9DdXLFqRfZbTo LK+FHdpQZBoQfzlfaKrj2G1Gv0vo5YuEGfFPisS4= Date: Sun, 17 Sep 2023 10:04:44 +0200 From: Greg Kroah-Hartman To: Krishna Kurapati Cc: Linyu Yuan , Maciej =?utf-8?Q?=C5=BBenczykowski?= , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, quic_ppratap@quicinc.com, quic_wcheng@quicinc.com, quic_jackp@quicinc.com, stable@vger.kernel.org Subject: Re: [PATCH v2] usb: gadget: ncm: Handle decoding of multiple NTB's in unwrap call Message-ID: <2023091743-tightly-drivable-4360@gregkh> References: <20230915061001.18884-1-quic_kriskura@quicinc.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20230915061001.18884-1-quic_kriskura@quicinc.com> On Fri, Sep 15, 2023 at 11:39:48AM +0530, Krishna Kurapati wrote: > When NCM is used with hosts like Windows PC, it is observed that there are > multiple NTB's contained in one usb request giveback. Since the driver > unwraps the obtained request data assuming only one NTB is present, we loose > the subsequent NTB's present resulting in data loss. > > Fix this by checking the parsed block length with the obtained data length > in usb request and continue parsing after the last byte of current NTB. > > Cc: stable@vger.kernel.org What commit id does this fix? > Reviewed-by: Maciej Żenczykowski > Signed-off-by: Krishna Kurapati > --- > drivers/usb/gadget/function/f_ncm.c | 26 +++++++++++++++++++------- > 1 file changed, 19 insertions(+), 7 deletions(-) > > diff --git a/drivers/usb/gadget/function/f_ncm.c b/drivers/usb/gadget/function/f_ncm.c > index feccf4c8cc4f..f00f051438ec 100644 > --- a/drivers/usb/gadget/function/f_ncm.c > +++ b/drivers/usb/gadget/function/f_ncm.c > @@ -1156,7 +1156,8 @@ static int ncm_unwrap_ntb(struct gether *port, > struct sk_buff_head *list) > { > struct f_ncm *ncm = func_to_ncm(&port->func); > - __le16 *tmp = (void *) skb->data; > + unsigned char *ntb_ptr = (void *) skb->data; Why persist with the extra ' ', didn't checkpatch complain about this? And why the cast at all? > + __le16 *tmp; > unsigned index, index2; > int ndp_index; > unsigned dg_len, dg_len2; > @@ -1169,6 +1170,10 @@ static int ncm_unwrap_ntb(struct gether *port, > const struct ndp_parser_opts *opts = ncm->parser_opts; > unsigned crc_len = ncm->is_crc ? sizeof(uint32_t) : 0; > int dgram_counter; > + int to_process = skb->len; > + > +parse_ntb: > + tmp = (void *) ntb_ptr; Again, no blank space please. And why the cast? thanks, greg k-h