From mboxrd@z Thu Jan 1 00:00:00 1970 From: Petko Manolov Subject: [PATCH] Fixes buffer allocation size and the actual packet length; Date: Tue, 26 Apr 2016 21:50:24 +0300 Message-ID: <1461696624-5373-2-git-send-email-petkan@mip-labs.com> References: <1461696624-5373-1-git-send-email-petkan@mip-labs.com> Cc: davem@davemloft.net, petkan@mip-labs.com To: netdev@vger.kernel.org Return-path: Received: from lan.nucleusys.com ([92.247.61.126]:42250 "EHLO zztop.nucleusys.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752395AbcDZSuk (ORCPT ); Tue, 26 Apr 2016 14:50:40 -0400 In-Reply-To: <1461696624-5373-1-git-send-email-petkan@mip-labs.com> Sender: netdev-owner@vger.kernel.org List-ID: usb_fill_bulk_urb() receives buffer length parameter 8 bytes larger than what's allocated by alloc_skb(); This seems to be a problem with older (pegasus usb-1.1) devices, which may silently return more data than the maximal packet length. Going through the chip's documentation i figured out the ethernet packet is appended with 4 bytes of status data. That's why we now subtract 4 instead of 8 bytes from the reported packet length. Reported-by: Lincoln Ramsay Signed-off-by: Petko Manolov --- drivers/net/usb/pegasus.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/usb/pegasus.c b/drivers/net/usb/pegasus.c index f840802..780c217 100644 --- a/drivers/net/usb/pegasus.c +++ b/drivers/net/usb/pegasus.c @@ -497,7 +497,7 @@ static void read_bulk_callback(struct urb *urb) pkt_len = buf[count - 3] << 8; pkt_len += buf[count - 4]; pkt_len &= 0xfff; - pkt_len -= 8; + pkt_len -= 4; } /* @@ -528,7 +528,7 @@ static void read_bulk_callback(struct urb *urb) goon: usb_fill_bulk_urb(pegasus->rx_urb, pegasus->usb, usb_rcvbulkpipe(pegasus->usb, 1), - pegasus->rx_skb->data, PEGASUS_MTU + 8, + pegasus->rx_skb->data, PEGASUS_MTU, read_bulk_callback, pegasus); rx_status = usb_submit_urb(pegasus->rx_urb, GFP_ATOMIC); if (rx_status == -ENODEV) @@ -569,7 +569,7 @@ static void rx_fixup(unsigned long data) } usb_fill_bulk_urb(pegasus->rx_urb, pegasus->usb, usb_rcvbulkpipe(pegasus->usb, 1), - pegasus->rx_skb->data, PEGASUS_MTU + 8, + pegasus->rx_skb->data, PEGASUS_MTU, read_bulk_callback, pegasus); try_again: status = usb_submit_urb(pegasus->rx_urb, GFP_ATOMIC); @@ -823,7 +823,7 @@ static int pegasus_open(struct net_device *net) usb_fill_bulk_urb(pegasus->rx_urb, pegasus->usb, usb_rcvbulkpipe(pegasus->usb, 1), - pegasus->rx_skb->data, PEGASUS_MTU + 8, + pegasus->rx_skb->data, PEGASUS_MTU, read_bulk_callback, pegasus); if ((res = usb_submit_urb(pegasus->rx_urb, GFP_KERNEL))) { if (res == -ENODEV) -- 2.8.0.rc3