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From:   Rusty Russell <rusty@linuxcare.com.au>
To:     "David S. Miller" <davem@redhat.com>, netdev@oss.sgi.com
Subject: Is mac address reference safe w/ zero copy?
Date:   Wed, 07 Feb 2001 23:13:51 +1100
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Hi Dave, et al,

	The following code in route.c:ip_route_input_slow()

		if (dev->hard_header_len) {
			int i;
			unsigned char *p = skb->mac.raw;
			printk(KERN_WARNING "ll header: ");
			for (i=0; i<dev->hard_header_len; i++, p++) {
				printk("%02x", *p);

	Is this safe w/ paged skbs?  Can I assume this in the ipt_mac
mac-address-matching netfilter module (which can only be called on
incoming or forwarded packets)?

Rusty.
--
Premature optmztion is rt of all evl. --DK