#1943: sk_buff->hard_header_len contains wrong LLC header size -------------------------------------+-------------------------------------- Reporter: [EMAIL PROTECTED] | Type: defect Status: new | Priority: minor Component: madwifi: other | Version: trunk Keywords: mac header illegal size | Patch_attached: 0 -------------------------------------+-------------------------------------- I am analysing packets with Netfilter ULOG and noticed, that the mac header is not exported to userspace.
The problem is that field hard_header_len of kernel struct sk_buff contains a size, which is too long. Because it is greater than 80 the mac haeder is not copied to the ulog_packet_msg struct (see net/ipv4/netfilter/ipt_ULOG.c). I patched the kernel to get the full mac haeder. Its size was set to 90B. Printing it showed, that following the actual LLC header part of the IP packet is included. This is probably, because the header and the packet is stored in a linear buffer. The correct size of the header would be 14B. I reproduced this behaviour on Ubuntu Gutsy (linux 2.6.22-14, ath_hal 0.9.18.0, wlan 0.8.4.2, ath_pci 0.9.4.5) and on a Netgear router WG302 running OpenWrt with Madwifi drivers from trunk (r3314). No problems have been observed with an Orinoco wireless card. -- Ticket URL: <http://madwifi.org/ticket/1943> madwifi.org <http://madwifi.org/> Multiband Atheros Driver for Wireless Fidelity ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Madwifi-tickets mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/madwifi-tickets
