netdev - Re: Is this 32-bit NCM?

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <87fvcyqoup.fsf@nemi.mork.no>
Date:	Tue, 02 Dec 2014 12:21:18 +0100
From:	Bjørn Mork <bjorn@...k.no>
To:	Enrico Mioso <mrkiko.rs@...il.com>
Cc:	Kevin Zhu <Mingying.Zhu@...iocodes.com>,
	Eli Britstein <Eli.Britstein@...iocodes.com>,
	Alex Strizhevsky <alexxst@...il.com>,
	Midge Shaojun Tan <ShaojunMidge.Tan@...iocodes.com>,
	"youtux\@gmail.com" <youtux@...il.com>,
	"linux-usb\@vger.kernel.org" <linux-usb@...r.kernel.org>,
	"netdev\@vger.kernel.org" <netdev@...r.kernel.org>
Subject: Re: Is this 32-bit NCM?

Enrico Mioso <mrkiko.rs@...il.com> writes:

> Kevin - it works! the key seems to be in the tx_fixup function; there is a 
> special handling for frames effectively.
> Please ... help me backport those changes to the standard Linux driver - it 
> will be a gain for us all, and in general you'll have a more probable 
> maintenance than you would with the driver from huawei.

Very interesting.  The NCM code in the huawei driver has a different
origin, so it is quite different and not too easy to merge into the
existing Linux cdc_ncm driver.

But this does pinpoint differences we should explore.  One is the
placement of the NDP: The Huawei driver puts it at the end.  Another,
which is much easier to test out quickly, is the sequence numbering: The
Huawei driver doesn't use it.

So I wonder if this makes any difference:

diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c
index 80a844e0ae03..37f11770acb6 100644
--- a/drivers/net/usb/cdc_ncm.c
+++ b/drivers/net/usb/cdc_ncm.c
@@ -1049,7 +1049,7 @@ cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
 		nth16 = (struct usb_cdc_ncm_nth16 *)memset(skb_put(skb_out, sizeof(struct usb_cdc_ncm_nth16)), 0, sizeof(struct usb_cdc_ncm_nth16));
 		nth16->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN);
 		nth16->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16));
-		nth16->wSequence = cpu_to_le16(ctx->tx_seq++);
+//		nth16->wSequence = cpu_to_le16(ctx->tx_seq++);
 
 		/* count total number of frames in this NTB */
 		ctx->tx_curr_frame_num = 0;



Bjørn
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html