From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oliver Neukum Subject: Re: Several races in "usbnet" module (kernel 4.1.x) Date: Thu, 23 Jul 2015 11:43:14 +0200 Message-ID: <1437644594.4377.12.camel@suse.com> References: <55AD3A41.2040100@rosalab.ru> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, LKML To: Eugene Shatokhin Return-path: In-Reply-To: <55AD3A41.2040100-irhHPgl+04UvJsYlp49lxw@public.gmane.org> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org On Mon, 2015-07-20 at 21:13 +0300, Eugene Shatokhin wrote: > [Race #5] > > Race on dev->rx_urb_size. I reproduced it a similar way as the races > #2 > and #3 (changing MTU while downloading files). > > dev->rx_urb_size is written to here: > #0 usbnet_change_mtu (usbnet.c:392) > dev->rx_urb_size = dev->hard_mtu; > > Here is the conflicting read from dev->rx_urb_size: > * rx_submit (usbnet.c:467) > size_t size = dev->rx_urb_size; Yes, but what is the actual bad race? I mean, if you change the MTU in operation, there will be a race. That is just unavoidable. Do we generate errors? Regards Oliver -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html