Wireshark-dev: [Wireshark-dev] regarding failed fcs and mac80211 subsystem
From: abhinav narain <[email protected]>
Date: Fri, 17 Feb 2012 18:15:01 -0500
 I am trying to get the code flow of mac80211 subsystem, 
 I notice a comment in  ieee80211_rx() before call to ieee80211_rx_monitor()

         * Frames with failed FCS/PLCP checksum are not returned,
         * all other frames are returned without radiotap header
         * if it was previously present.
         * Also, frames with less than 16 bytes are dropped.

This suggest the frames with bad fcs are not forwarded up !
How does pcap get the bad fcs frames for wireshark, in that case ..  ?

Does someone has an idea if mac80211 subsystem does any checksums on the packet headers/packet as a whole ? 
I am unable to find it if it does so only on the packet (contained in sk_buff) data [TCP/UDP/other protocol data region] ?