On Tue, 1 Apr 2003, Rask Ingemann Lambertsen wrote: > Is a network device driver allowed to modify dev->flags? For example: > > if (dev->flags & IFF_ALLMULTI) > dev->flags |= IFF_PROMISC; You must be looking at the atp.c driver, or a driver that cribbed from it. (Is anyone still running a parallel port Ethernet device?!) Alan Cox added this code to atp.c because the chip doesn't have a reasonable multicast filter. The only way to receive all multicast traffic was to turn on promiscuous mode. But that caused a problem with some parts of the protocol stack were passed traffic not intended for the local host. A better solution (which is usually easier to see later) is to have the driver do the trivial final packet filtering itself. > I've found it to cause the IFF_PROMISC flag to stick when using > "tcpdump -p", which to my surprice sets the IFF_ALLMULTI flag. Which driver are you using? -- Donald Becker becker@scyld.com Scyld Computing Corporation http://www.scyld.com 410 Severn Ave. Suite 210 Scyld Beowulf cluster system Annapolis MD 21403 410-990-9993 - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
